A big congratulations to Pangea! I’ve always loved the Aerospike engine and always believed attempts to perfect it should never stop. Thank goodness for never stopping.
Can't waiting till my children are graduating from an actual Terran Academy. Every episode is a university level lecture. I had never heard of grcop alloys. Thank you for all of your research and smart work.
Good point Helix... We have watched it... and it is an excellent assessment of previous attempts at aerospikes. He did not of course address advanced alloys or this engine... which did not exist when he made the video.
Glad it was helpful Steven! We try to balance providing an overview that is clear and concise with enough technical details for those more interested in the data and details. I am a also big picture person, but often force myself to go through the calculations so I can compare and fully understand different systems.
Amazing work by Pangea, and thank you for the video. Now that it has been shown to be possible, the floodgates will open. Perhaps Blue Origin could swap an aerospike in place of their combustion chamber to solve instability problems. I'm sure SpaceX will be watching too, and most of the small outfits like RocketLab, as the efficiency and comparative simplicity of the build must offer real benefits. Great that NASA has promulgated the groundwork too.
impressive, key take away the improvement and implementation of material science. Thermal management of aerospike has always been its downfall. 3D printing is proving to be gamechanger on so many fronts. I would love to see someone like Elon take this material break through and run the distance on this engine. Not requiring sea level or vacuum optimised variants is already such a mass benefit. I would really love to see the ISP, even if 20-30 lower than others it is going to revolutionise. Nice work
Aerospikes do have the disadvantage that by the time you would be switching to a different engine, you'll want to drop an empty fuel tank for optimization anyways- this undermines the advantage of an engine that adapts to altitude, especially since aerospikes don't operate as efficiently as a conventional engine optimized for where it's at.
Another excellent inspiring presentation. As a retired engineer my gut tells me Aerospike will prevail until some brilliant physicist defeats gravity somehow in the not so distant future.
I've always been a fan of Aerospike engines... thermal issues have been the big bugaboo, but there are some other issues like reaction efficiency due to the non-existent reaction chamber. Overall, I'm glad they are being given a REAL tryout!!
Thanks for the video. I don't normally have the attention span for 20+ min vids, but I'll make an exception for yours. The GRCop-42 could have application for the flow path liners of scramjet engines. When we tested workhorse NASP scramjet combustors in the early 90's at GASL we used Narloy-Z. It was too heavy for flightweight hardware. Integral coolant passages would have been impossibly expensive at that time.
Hello, excellent videos. Do you know which software language is being used by these new startup Space companies? I have to write our engine control software, but which language? Thanks for the videos full of inspiration. Douglas Ray Renzoni CTO
Yes, it's amazing that a small European startup achieves this state-of-the-art "Aerospike" engine. It's unbelievable that Nasa didn't persist in such an amazing technology. This Spanish Aerospace company - Pangea - made history. What next? European SpaceX fan.
There is nothing Elon is doing that other's cannot do. There is no reason why Europe cannot build something to rival Starship. French and German engineering are some of the best on Earth. Most cruise ships and yachts are built in Europe. Elon might be showing the way but soon many more nations will follow.
@@terranspaceacademy 14:50 This is very flawed economic theory. The government creates no wealth, hence the 70k EUR was extracted from another part of the economy, preventing private investments, which for all we know could have been in space technology. Moreover, you're only presenting one example that you consider a success. You're not seeing all the other government investments which were also extracted from somewhere in the private economy and did not lead to anything useful (or worse, were invested in programs that reduce economic growth, e.g. trade restrictions).
@@phamnuwen9442 Very high risk investment such as this initial Euro 70K does not generally provide the security to the average investor, nor allow for the original motivators to retain active control of the company and its R&D direction. Thus finding monies to carry a project forward is often prohibitive. OTOH govt investment from an array of financial and R&D packages allows for the potential spin-offs, retention of talent and resources, plus the downstream potential for tax and FX revenue plus employment. I had resigned as director of one promising R&D company due to the duplicity of its finance director trying to maximise his return, long before the company had 'legitimately' achieved its goals. His share of the company also diverted priorities away from R&D into posturing. Thus an excellent innovation is now rusting away somewhere in Holland.
I always suspected that the issues of TWR with the XRS-2200 and J2 derived aerospike were that they were using the plumbing and turbomachinery of dedicated deleval bell engines, and not a fundamental design flaw of the Aerospike engine. It's a good step towards the rotating detonation aerospike which I think is pretty close to the pinnacle of bipropellant LPREs.
It would be indeed... the manufacturing techniques/AM had to exist before the aerospike was possible... then with GRCop-42 and similar alloys in an expander cycle engine heat is a good thing :-)
Great lesson! Years ago, I had some beryllium copper tools I got at a flea market...I was told they were used around flammable gasses...strong as steel, and won't make sparks. Nickel and chrome is the resistance wire for heating elements..gets hot, won't sag. It's the glowing strips in your toaster. I agree wholeheartedly that 3D printing is the future of manufacturing...space and otherwise ..
I did not know the toaster wires were nickel and chrome but it makes sense! Makes you wonder what alloys we can make once we get really rare metals like osmium and iridium in larger quantities from metallic asteroids and psyche :-)
@@terranspaceacademy It's sold as " Nichrome" and has been around for decades . In the past, you could buy it at hardware stores..it was sold by watts per inch...back when appliances were meant to be repaired. Psyche 16 is supposed to be a treasure trove of rare metals ..
Beryllium powder may be poisonous. Berylliosis! it seemed to have been used in the 1st Nuclear Age at Oak Ridge National Lab with their Molten Salt Reactor Experiment MSRE the reactor was built with Hastelloy-N, thermally annealed.
Wow... again another excellent video discussing a number of subtopics that build into a breakthrough in Aerospike engine development. Interesting discussion on Copper... one more of the many uses of copper that I've heard throughout my life... Like ... my copper integrated socks I got while in AFG, which helped keep my feet cooler in my combat boots, must've took advantage of copper in a way to handle heat like those rocket engines at a lower level ... LOL Man, I could use a black version of those for work now ... Santa did you hear that? Next the 3D printing will change a lot of things not only for space but like in the military with part making forward on the battlefield than shipping it from a factory on the other side of the world. Why carry massive tool sets with specially tools when you can have your basic set and print when as needed for special ones... forward operating 3D printers will change the future from the old days. Again, thanks for teaching this old dog something new!!!
Terran spae acedemy, can you send me the link to the white paper or source on the thrust/isp of the aerospike engine? i cant get the second additional information link to work
They are playing things close to the vest for now... pangeaaerospace.com/propulsion/ the Isp of aerospikes has been best examined here... scholar.afit.edu/cgi/viewcontent.cgi?article=2329&context=etd though these are linear and we'll have to wait for Pangea to publish theirs..
I love what NASA does, they tried to make airospikes work and got close, but for reasons beyond their control were unable finish, so they got funding to work on the remaining problems and made their resaults available to others, they still get airospikes. I am an Australian and I think it is fair to say that all countries admire, or in some cases envy NASA and their achievements. I hope Pangea Aerospace succeeds, they deserve to. I notice others on this thread suggesting that SpaceX's near future non-raptor engine may be an aerospike, I am thinking along the same lines, after all, Raptor is based on technology developed to a similar level that also did not previously fly.
We agree completely about NASA... on the shoulders of giants David. We are very proud of Pangea and wish them the best... we think there will be a rush on GRCop-42 and probably other variants, with 3D printers so advanced now I expect a paradigm shift and it would be great if SpaceX led the way.
I think it would be hard to do much better than Raptor for SpaceX's purposes with chemical rockets unless they went for an aerospike variant, which would also give a good reason for a name change.
And NASA is still getting the credit for funding cutting edge research that is only now paying off ! Wonder what research NASA is funding at the moment ?
I would like to see Spacex develop Raptor2 alongside an aerospike version of raptor ( I am going to name this pet raptor Spike). One team on raptor2 and one on Spike should give a true comparison between the two, although to be fair to Spike he needs more development time to catch up.
Rockets built by private industry is hard. You have to put in a lot of money into infrastructure, into supplies, wages, land, permits and all of your first builds will blow up or fail. There are a lot of different technologies coming together (propulsion, electronics, materials, software, aerodynamics, avionics, etc)
Well, hopefully NASA is sharing the material science info and other related knowledge with American companies. Do they license that info and just prevent them from creating weapons and sharing tech with other nations? I would think that say a formula for making an optimized rocket nozzle, early rocket designs, aerodynamic studies and other things up to at least 1980 or 1990 should be available to citizens to get a jump on building a modern rocket. When we have this huge time lull of nothing new going into space, the old engineers retire and die. We need to keep passing on this knowledge.
I want to see what these guys that 3D print an entire rocket can do. Is SpaceX 3D printing any of the engine parts? I like that they're using a relatively cheap stainless for Starship. I'm hoping it is rapidly repeatable like they say it will be. I wonder if they could scale it down to make a next gen Falcon 9 for small payloads. Maybe just use 2 or 3 Raptor engines. And also make the Starship XXL as a tanker or heavy lift to get a crane, InSitu fuel generation plant and other big things to Mars and Moon.
A bit of a misnomer, honestly. Without "greed" legacy space contractors wouldn't've been around and wouldn't've bothered to accept those big fat government checks to get Apollo done. To this day those same contractors still propose revolutionary architectures like ACES/XEUS, Mars Basecamp/MADV, or the innumerable advanced engine development programs that have been lead by NASA for the past four or five decades. The problem is, NASA has neither the funding nor the mandate from Congress to actually carry those projects out to completion, build vehicles with them, and make them useful to humanity. What's really wrong with the legacy space model now isn't really greed, it's government complacency and stingeyness. That's why the Rocket Labs and SpaceX's of the world have had to step up and try to fill those boots instead.
A footballer may be 'greedy' for wanting to score goals or touchdowns. There is much the same motivation in the financial markets, where the accumulation of wealth provides much the same emotional and status rewards, as well as presenting technical challenges and risk. The term greedy tends to be most generously applied by those who have achieved little, to those who over-achieve.
Thanks for an enlightening presentation. But at about 18:45 you stated that nothing will ever beat an aerospike for a chemical rocket in space. That is correct for the moment until someone comes up with an even better rocket design/material. We stand on the shoulders of giants and in the future others will stand upon our shoulders. Chemistry, physics, and mathematics grow and evolve. I do believe that there is more that we do not know than that which we do know.
I have no doubt you are right in general :-) much better things than chemical engines will be invented at some point. But aerospike engines optimize the energy produced by a chemical rocket. Like Elon saying the Raptor combustion cycle efficiency is less than 1% from perfect.
@@josephparker3033 That efficiency figure only holds if you can't escape the limits combustion place on energy gain. So if you could change the situation/limits you might be able to squeeze yet more energy out. In this case I've also actually heard of such a method via use of a detonation wave, which as such lets you exceed normal combustion energy returns, at the cost of now needing to control a rather dangerous phenomenon in your engine, detonation waves tend to like to detonate things after all. Still they've been working on that in for instance jet plane engines and apparently gained another 5% or so there in testing. So if that holds for rocket engines as well, it might be possible to squeeze just a bit more efficiency still for a rocket.
just 3 futuristic words, I want to type in: Lofstrom Launch Loop (kind of a continuous ballistic artillery, with excess kinetic energy recycling) For planet earth maybe Aerospike is more feasible. For operations on the moon I think LLL would be quite an interesting alternative.
DED also has the advantage that the alloy can be made in the print head and the percentages of the constituent parts can be varied across the part so that each part of the structure can have a tuned alloy to meet it's specific requirements.
Very good question. We won’t be able to truly know until they make one function as well as the Pangaea engine but the specific impulse should be better.
Nice presentation folks! But can you put up some tech data here like overall mass of this engine and its volume; the thrust we already have ;) . Also shed some light on the way its feeding its fuel. In the test thers no turbopump visible. How does it work and what kind of cycle? Is an expansion cycle without preburner even with methalox possible due to that vast heat excess?
After seeing rocket engine engineering stagnate for decades with engines developed in the 1950s and 60s (ie: AJ-10, RL-10 & RD-107) still being used today as front line technology, I was overjoyed when SpaceX showed that it was possible advance the state of the art with a full flow staged combustion methane engine. Apparently inspired by SpaceX and NASA we are finally getting a workable Aerospike. Now if they could just get the SABRE is an air-breathing rocket engine to be practical.
The SABRE technology is sound... research funding is the problem. if they had put it in a fighter jet it would have all the funding it needed but none of us would hear about it for a long time.
Since there is no public data available about the actual ISP of those new engines, we have to be very couscous about their efficiency claims. Especially in a vacuum all aerospace engines I could find data for, do lose out against well made comparable vac-nozzle engines. It would be really interesting to see what data let you to the conclusion that aerospikes perform better in vacuum than conventional bell-engines.
@@terranspaceacademy An Aerospike is NOT an infinite nozzle. First of all the spike has a finite length. Secondly as the air pressure is going down with increasing altitude, the effect of the "virtual outer nozzle wall" becomes less and less useful. This increases vector losses, as the _outer exhaust_ gasses are not directed anymore. In vacuum they leave the nozzle at 90° to the flight vector. So in essence an aerospike engine is 100% underexpanding in a vacuum. The exhaust gases exiting the nozzle throat are directly hitting the vacuum without the chance of being "slowly" expanded by a bell nozzle.
An aerospike works "as if" it were an infinite nozzle... I will differ to those who know more than me, and NASA... who say the aerospike is much more efficient in vacuum than the bell nozzle. "At low pressures, however, the nozzle operates in a "closed wake" state. Since the base is not subject to a high ambient pressure, there is no altitude compensation benefit, and the aerospike behaves like a high area ratio bell nozzle. Thus, in theory at least, the aerospike nozzle meets or exceeds the performance of the bell nozzle at all operating pressures." "A way to visualize it is to imagine the gasses moving between two opposite walls which are coming closer to each other and then beginning to separate. At the point where the gasses have reached some low supersonic speed, one of the walls ends. This is the point where the external expansion ends. The other wall continues down and forms the spike contour. At the point where the other wall ends, the gasses expand around the edge of the wall. The amount of expansion is determined by the ambient pressure on the other side of the wall, the one which has ended. For details on the fluid process involved, look in any compressible flow textbook under the section on expansion fans and Prandtl-Meyer flow.(1) This is the source of the altitude compensation. As the ambient pressure drops, the gasses make a sharper turn around the edge. As the gasses turn the pressure drops. The amount of turning is determined by the pressure difference between the combustion gasses just arriving at the edge, and the ambient air on the other side of the wall. A good reference for this material is Modern Compressible Flow with Historical Perspective by Anderson. HOW DOES IT WORK IN A VACUUM, WHEN THERE IS NO AIR PRESSURE TO CONSTRAIN THE EXHAUST? The air flow around the aerospike nozzle exhaust is not what constrains the plume but rather the ambient pressure. Therefore, whether or not the nozzle is moving, the exhaust plume will be more or less the same (shear layer effects between the nozzle exhaust and the quiescent air being neglected, of course). In a vacuum there is no ambient pressure to constrain the exhaust plume and the turning angle of the plume will be (approximately) determined by Prantl-Meyer expansion wave theory. A good reference for this material is Modern Compressible Flow with Historical Perspective by Anderson"
@@terranspaceacademy Thanks! Interesting read. Can you give me the link to the source? I have to say I'm still skeptical about _"theory vs reality"_ here. Because if the Prantl-Meyer expansion waves were as good at directing the exhaust gases as a high area ratio bell nozzle, then all vacuum optimized nozzles would end just after the throat. I know that tiny attitude thrusters for satellites are often cut off just after the throat. The losses of the gasses "rubbing" on the inside of the bell would offset any Isp gains from the expanding nozzle.
Can you place the printer in a noble chamber gas chamber to aid in eliminate the exposure to iron and oxygen? Possibly aiding the successful production of that alloy.
You'll need a lot more than 21. The upper engine thrust vector will be outward. The net downward component needs to be a bit bigher than the vehicle weight. About a thord of the thrust will be wasted squeezing the vehicle.
@@terranspaceacademy They don't face directly down. they face outward about 20-30 degrees from the rocket's long axis. Not all of the thrust force from each individual rocket is directly lifting. Picture the force vector of each individual rocket. about 30% of its force isn't lifting. its pushing sideways.
The US Navy used a concept on SLBM's to save space where the nozzle actually slides down and locks into place after it is ejected from the water and ignites onto a shorter nozzle and when it does it makes what is called a regular atmosphere nozzle. Why cant a similar system be used to extend the nozzle when the rocket starts reaching vacuum to turn it into a vacuum nozzle. The best way I can explain it is the plastic cups from the 70's that you could carry in your overnight bag that compact into a small disc. When you want to use it to drink you pull the plastic cup until it extends to make a cup. Same concept for the atmosphere to vacuum engine.
I would add ethanol to the list of suitable fuels for aerospike. Regarding the heath-resisting alloys, the field of study has tired toward monocristalline nitride-free nickel alloys, as nitrogen weakens the bonds inside the alloy lattice. As the purification is achieved via a cooling profile, I don't know how printing fits into it... Thanks for the great video...
I know everybody will pan this but I like the idea of those smaller rockets placed axially up each side of the lunar lander starship variant. Once the booster let's it go, they no longer need flamey end down or pointy end up. So a number of smaller engines on the sides could put it into orbit because there is so little atmospheric drag. It would just pitch nose over and blast up. This would allow the interior to be laid out with full length flat floors on 3 or 4 levels. Some of which could serve as tanks when needed or as habitable space other times. It allows for landing vertically in a horizontal position and use loading ramps to roll freight on and off, and easy access for personel. With smaller engines aiming a few degrees away from vertical they could be closer to the moon surface. There it is, a mental toy to play with. Try not to ruin it. Lol
One thing I've always wondered about Aerospike engines is how well they would perform with multiple engines next to one another. They rely on atmospheric pressure surrounding to provide a neutral expansion, but wouldn't there be severe issues with an uneven pressure surrounding the engines when they are arranged next to each other? My guess is this would cause vibration issues in the engine at minimum, even if it didn't affect efficiency or thrust. I'm not sure I've heard whether this would be an issue or not. It may be it doesn't matter, but I'm curious as to the implications. For a re-usable system you would have to have either multiple engines (so you can use just a few of them for landing when the ship is lighter) or have a very high level of throttleability on a few, or even one, engine. The latter makes any engine design more tricky and usually much more expensive. So right now it almost ensures you would have to have multiple such aerospikes on a re-usable system, even if it is a two stage one.
This is a great question... aerospikes will adjust to the outside pressure... this would include the pressure of nearby engines... the aerospike, by its nature, will adjust itself for different pressures on different sides. This should not transmit any force back the aerospike that I can see... but I will be happier when we has flown and we are sure :-)
Very i.pressive indeed! Seriously hoping that this is what Elon Musk was reffering to when he said that he will need a new generation of engines beyond the raptor!
Wouldn't it make sense to combine this aero spike tech and RDE with lower atmosphere air-breathing capability to make a commercially viable SSTO a reality?
With enough printers... which I think SpaceX would make a better cheaper version and start selling... I have no doubt it would save time and resources while simplifying production.
The general public's standard or what constitutes proof is terrifyingly low and off target. That is probably the single biggest threat to civilization we face. The fallout of that touches every aspect of life negatively.
We've looked at that... hard to do but not impossible. We were looking at a wider throat with a spherical obstruction and vanes to hold it in place tapering to an aerospike on the bottom. it might be better to just revamp the combustion chamber entirely though...
Is annular the best aerospike configuration ? Looks like linear would be the way to go now that the metallurgy is solved. That was NASA's original intent for the Delta Clipper.
We love linear aerospikes for several applications... the annular aerospike will probably scare your investors less :-) It looks most like a "regular" rocket engine...
Good question! The average reentry temperature on the surface of a ship is about 1650K from absorbed photons coming from the shockwave (11,000K)... these engines burn much higher than that... it should be possible to actively cool a reentry ship as long as the heat is rejected out the engine.
@@terranspaceacademy is there a possibility to use new material as “heat shield” with scales, or to 3D print the hull and circulate a gas or insulate the air gap. I also noticed some material being added, like a coating, could that be added to the exterior of a structure as a heat shield?
Doesn't the concentric rings of engines around a central engine effectively accomplish what an aerospike does? With the gasses from the center engines making the inverted bell out of exhaust gasses. With the engine layout of the starship booster for example. The center engine creates a plume that helps direct the next ring of engines. These engines could even be pointed towards the center at sea level and outwards at higher altitudes. Then again with the same on the outer ring of engines. This of course wouldn't apply to single vacuum only engines. But doesn't it make them not worth the bother for multiple ascent engines.
Thank you for the information. Can I recommend a little background music? The tone and cadence of your voice wants to put me to sleep, no insult intended.
You are not the only one to notice that David :-) I used to have it in the background but we had several complaints that it made it harder to hear the narration... we'll try to find a happy medium.
Well this seems like excellent news, yet another potential efficiency gain for future rockets. Though probably will take awhile to be fully tested out and possibly scaled to the power levels various companies might want. One wonders if SpaceX will take it in to consideration for a future complete redesign of the Raptor as well.
@@terranspaceacademy Yeah, I'm not sure what to think of the suggested not-Raptor engine either. At the moment I can think of but three directions you can go in based on the statement made, a major redesign to increase reliability and reuse, which of course would be important. Trying to squeeze every last second of ISP of a radical new design you can to make the very tight margins not so constricting, like adding an aerospike and detonation engine concepts. Or truly go radical and consider something like a nuclear engine. If I were to guess then the first or second seem more likely then the third at this time.
No need to apologize... the expander cycle could limit rocket engine size but since the aerospike is a master at generating heat load we should be able to get a very large engine out of it :-)
Size is limited with expanders however stating with the liner Aerospike would allow for many and they would have to engineer the engine kinda backwards by trying to create as much heat as possible. Increasing fuel flow would take away more heat and optimizing the fuel oxidizer ratio would create more. Granted they could only take that aproach so far before they start running into all kinds of other problems
I'm still hesitant as far as wild changes in current technology, but we are getting there.The exciting thing is technology isn't static. In a recent Tweet, Elon Musk said that the current Raptor will not be the engine in the final analysis. They are presently working on new technology which won't be called Raptor. Who knows what that might be.
We were shocked when he said that... the Raptor is so well refined at this point... it must be something revolutionary. Fingers crossed for aerospikes.
I'm late to the party, but heat is still the reason. With moden alloys, ya you could probably get something like a merlin powerhead to drive an areospike, it might even be a little better. But Rapor is on another level. Tested to 330 bar, made with those same modern alloys, and he is saying they are still having a hard time keeping the thing from burning up. With what was it, 4x the throat area? it's a currently unmanageable heat load. Raptor is going to outperform any areospike that's able to keep itself cool. That being said, Raptor is designed as super heavy engine. For a smaller orbital taxi application, sure. I have no idea how you believe 21 of those things is would be in any way better than 6 raptors. The plumbing alone would eat up your mass savings. You also can't can't use areospikes to land without orbital debris being kicked up. How would you propose mounting those in the side of the lander? Those won't be raptors either.
But the "new" (NASA came up with it in the 90s) alloy is truly revolutionary Corey. And you could coat with inconel or titanium for added strength... the heat actually becomes a blessing if you go expander cycle. We don't have large expander cycle engines because heat harvesting is limited in bell nozzles as size increases. This is not a problem for aerospikes. We could have a 3MN aerospike expander cycle engine. They would be mounted at a 15 degree angle to the vertical... 21 of them would have enough power and provide redundancy... just like 33 Raptors on SHB... and they won't kick up any more debris than a bell nozzle would...
@@terranspaceacademy Nozzles just fit better for a flush mount like the descent engines on Starship. Raptor is Full flow staged. Much higher chamber pressures than an expander cycle. Chamber pressure is where Raptor is getting its efficiency from. I hate to say it but if an aerospike could withstand that, Elon would at least made a prototype. Rocket Lab has a CEO that knows areospikes, and they are building a new lift vehicle right now. It's primary feature will be durability. So why no areospike? This copper alloy isn't exclusive, you think these companies aren't using it?
See those stress tables, yet they are not very usefull without point of reference like stainless steel, high carbon ferrite(not sure if it can be used due to brittleness), inconel(well would eat budgets), copper for reference, even alloys of titanium.
That's a good point... The copper is not stronger than those metals... just stronger than pure copper and able to withstand the stress while still conducting sufficient heat to allow cooling...
I can't help but put on my psuedo engineer Kerbal hat on here and think about some what-ifs. So here goes- what if you could somehow get the TW ratio high enough to get it into the ball park of a Merlin engine? What-if the aerospike could be useful, not as an atmosphere optimized engine, but as a vacuum-optimized engine. Could there be an engineering path where an arrangement of nozzles could mimic an expansion ratio of over 500 with a relatively small nozzle making it much more compact than even a sea level engine? Since the aerospike engine uses several smaller engines, it should be able to throttle these engines for effective thrust vector control, no heavy hydraulics needed and a nice weight savings. Finally, lets throw in some rotating detonation engine tech with all of that and I would probably bankrupt SpaceX with all of these development projects. But what an engine that would be!
You are right on the money Brett... think of an array of these on the bottom of a large saucer shaped ship built on the Moon... then spin the saucer to get artificial gravity :-)
Hold on a second, who told you that an aerospike is tough or hasn't been researched? The Air Force fired the first liquid propellant aerospike in the late 50s, NASA experimented with them in the 60s (even planning and designing one based on the Apollo J2 to replace the Apollo J2) and both solid and liquid aerospikes have been tested multiple times in the last two decades. Yes the Starship, (should we ever see one actually built) would greatly benefit from an aerospike. Heck it would even do better with a standard plug-nozzle or even a plug-cluster since the Raptor doesn't have the needed throttling to handle landing well. Aerospikes were NOT "invented for SSTO's" they were initially studied for use in multi-stage rockets. In fact a type using what we call today a "Thrust Augmented Nozzle" was tested (and patented) by Aerojet in the early 1960s. The "plug" or blunt aerospike nozzle was in fact proposed and tested to be used at both a propulsion engine AND a heat-shield for reentry and recovery. You also need to be clear that the LINEAR aerospike had issues BECAUSE it was a linear design. The NASA and Air Force round aerospikes, (and plug-cluster nozzle designs) had fewer cooling and mass issues. (A big part of the mass issue was in fact the mechanisms to allow gimbaling of the entire nozzle which was not actually planned to be required in the operational engine) Part of this was because the standard "plug" aerospike was (as noted above) also planned on being an actively cooled reentry heat shield so unlike the linear aerospike they had a much better and more effective cooling system. Plug-cluster engines use pretty much 'standard' rocket engines in cluster around the 'plug' and therefore also have a better cooling system. "Hydrogen and methane" being the only propellants that can 'reasonably' be used to cool an aerospike engine again misses that aerospikes have been run on other propellants successfully up to and including solid propellant and an ablative 'aerospike'. I understand that research into such things is actually more difficult today due to the vagaries of the internet but really this information IS out there and available. I need to ask if you've ever heard of a site called "Secret Projects"? (www.secretprojects.co.uk/) I'd recommend it for some basic research before you expend a lot of effort on some of these false premises. Grats Pangea but they are FAR from the first here except in maybe 3D printing the engine. (And btw the earlier aerospikes were not built using 3D printing so that's another "opps" on your part, they can and have been built using more standard construction)
Thank you for your feedback Randy. This discussion started with why Starship would benefit from aerospike engines. This would mean liquid methane cooled. It is not our goal to discuss and argue everything that has ever been conceived. We try to keep the lesson length to something reasonable. The Pangea engine was never described as the first liquid cooled aerospike in concept... And linear aerospikes were discussed at length in another lesson with videos of the NASA tests. The point was that NASA had to stop their research for funding issues but was able to prove the metallurgy necessary for a 3D printable copper alloy that would be better than anything designed previously. This is not a false premise. It is a fact. Pangea was noted to be the first to build and test a functioning methane fuel aerospike. Methane is the rocket fuel of the future. It is not impossible to make aerospikes with other fuels, this has been discussed also. The point we made was that only methane and hydrogen can be used effectively in an EXPANDER cycle engine. In the end someone somewhere has usually thought of almost anything someone tries to do, or tried it and failed. Yes aerospikes have been built with other construction methods out of other materials, we made that clear. That does not change the fact that Pangea has succeeded where others have given up. If there are other companies with functioning aerospike engines in production and being ramped up to fly bring them to our attention please. Everyone makes mistakes. We are always willing to admit when we make an opps... did you mean "oops"? See? Happens all the time...
@@terranspaceacademy "We are always willing to admit when we make an opps... did you mean "oops"? See? Happens all the time..." Even with spell checking, far to often :) "Thank you for your feedback Randy. It is not our goal to discuss and argue everything that has ever been conceived. We try to keep the lesson length to something reasonable." I realize and appreciate that but your lesson gives a false impression which is why I spoke up. "This discussion started with why Starship would benefit from aerospike engines." Greatly and for a variety of reason you actually don't touch on but not all in the way presented. For example the use of aerospike engines on the upper-portion of the Lunar Starship, (which are supposed to be pressure fed "mini-Raptors" that the Air Force paid SpaceX to develop but they never did) would be a disaster. Specifically a "scarfed" nozzle set (ntrs.nasa.gov/api/citations/19900015790/downloads/19900015790.pdf) would be vastly better as it helps eliminate the heating from the engine plume which without a nozzle would require the skin around and below the engine exhaust to require active cooling itself. Using scarfed nozzles the section integrated with the skin will already have cooling channels built in. Another example is aerospike engines on the Starship would eliminate the problematic and troublesome "engine bay" which consistently causes issues on every flight and is an all around (and well know to everyone but SpaceX it seems) "bad idea". I'll note that it would also force SpaceX to finally invest in actually designing and building actual "landing legs" for the supposedly "reusable" Starship. "This would mean liquid methane cooled" Understood but you state that ONLY liquid hydrogen and liquid methane can cool an aerospike engine which is patently false. Which was my point. "Methane is the rocket fuel of the future" Arguable on all levels as it takes more steps to produce and is less efficient than liquid hydrogen despite that fuels operational issues. It has advantages but its current popularity is largely based on it's Terran availability as liquified natural gas. "The point was that NASA had to stop their research for funding issues but was able to prove the metallurgy necessary for a 3D printable copper alloy that would be better than anything designed previously." While there were funding issues if you read the reports the program had reached a point where it was going to be turned over to industry anyway. NASA does not "produce" its own products so that's the 'natural' process anyway. In fact those reports note that many rocket engines companies are looking to use this alloy in the future in the very form tested by NASA; As a 3D printed insert for conventional rocket engines. "This is not a false premise." I never said it was but there are many assumptions and statements in the lesson that reflect false premises on other areas. That's specifically what I was calling out. "Pangea was noted to be the first to build and test a functioning methane fuel aerospike." Yes but not the only one to build or test functioning liquid (or solid) propellant aerospikes and even fly them. "Yes aerospikes have been built with other construction methods out of other materials, we made that clear. That does not change the fact that Pangea has succeeded where others have given up." You assume that other companies 'gave up' simply because aerospikes are not in common use but that's a false premise right there. Pangea is building them because THEY want them. There is currently no 'market' for such an engine outside Pangea. Other makers of aerospike engines have found little interest in such engines and therefore have not produced them but that in no way equals them 'giving up'. Specifically most engine manufacturers have continued to research and improve the designs and Pangea has partaken of this knowledge and data base. "If there are other companies with functioning aerospike engines in production and being ramped up to fly bring them to our attention please." And that's called moving the goalposts :) Has Pangea actually flown one of these functioning aerospike engines? If not then they are already behind several other startups and even NASA who actually have flown such engines. Ramped up? Again, why since there is no demand or market. "Pangea wins" only because the criteria are selected so that only Pangea CAN win. (They have not yet won because they only PLAN on production and flight but have not done so yet so do not meet the criteria you post :) ) "The point we made was that only methane and hydrogen can be used effectively in an EXPANDER cycle engine." False actually. ANY cryogenic propellant, (and yes that includes LOX as the Soviets tested a LOX expander cycle in the mid-60s) can in fact be used in an expander cycle. My personal "favorite" is cryogenic propane, (liquid propane cooled to LOX temperatures) which has about 80% of the efficiency of hydrolox but is dense enough to fit into the same space as RP1. (Meaning if used in something like the Falcon 9 upper stage you can have about twice the performance of RP1/LOX) I'm all for trying to spread information about space flight and technology but it bugs me when I see heavily biased information that is also incorrect or misleading. We have enough of that from the likes of Musk and Zubrin who are seen as 'experts' on the entire subject by far to many people and who constantly show their lack of depth in either planning or knowledge which itself then spreads to the community. Like I said I like your videos, (except for the heavy SpaceX/Musk bias but that's kind of endemic these days unfortunately) but I reach a point where I have to speak out and I thank you for listening and responding.
Interesting video, though I’m not sure we can congratulate Pangea entirely, as it sounds like the alloy development and 3D printing research required to make it possible would never have happened without NASAs work and $$$$ (at least not yet) - leaving aerospike development at a dead end again.
You are quite right... That's why we in depth into NASA's and the Glenn Research Center's contributions instead of just saying... made of a copper alloy... like most of the news articles did :-)
would a steam-powered (or supercritical H2O ) linear aerospike be useful underneath Elon Musk's launch stand, just to blow away the exhaust gases in the first few seconds? it could also ameliorate the vertical sound waves, hitting the ground directly underneath the launch pad. I think the originally planned Water-Deluge system is not optimal, because it put additional resistance to the rocket gases at launch
Very interesting... create a suction type megavacuum effect? Very cool idea... it you could angle the aerospikes out at 30 degrees from horizontal or so...
@@terranspaceacademy>>> I am currently rewatching this video. I keep thinking your _voice_ sounds _familiar._ It then hit me why: You sound like actor Gil Gerard, who played the title character in the 1970s science fiction TV show *BUCK ROGERS IN THE 25TH CENTURY.* {Really.}
that's pretty tiny thrust. 20,000 newtons is only just over 2 metric tons. a raptor engine is about 225 tons and they are putting 31 of them on the first stage.
I think they should buy an uninhabited island in international waters and declare it an independent nation. Then they control their own spaceflight rules...
With a specific impulse of around 200 seconds it was a hard sell with just h2o2 over a catalyst bed. Then they said they were going to turn thousands of liters of water instantly into steam with batteries... I had hopes but the tech isn't there.
Congratulations on covering such a wide array of information, in sucjh a small time frame. Your "exact" data, contained many errors. Still, you produced an amazing piece of information. Of greatest note: your continual references to only two of the space-able groups. (there are more than 12 !)
Thank you Dirk! I'm not sure I ever refer to the information I glean as "exact" though... please send a detailed list of errors to terranspaceacademy@gmail.com and we'll be sure to do a correction burn and avoid repeating them.
Let SpaceX learn to fly their ship. Then they can improve. It does not make sense currently to make it more complicated. Currently. Just for now. Later they can improve it when it makes sense. They will improve it when it makes sense, of course they will.
Well some have broken the laws of physics, but have had their lives threatened or work for the government under non disclosure agreement. I was going to throw this argument at you, my point being that without the suppression we would have had open anti gravity almost a century ago. Look into the work of Walter Bosley.
I think ion engines with kilonewtons of thrust evolving to meganewtons will bee the following to chemical rockets, and probably before we get to mars. Lol
@@terranspaceacademy we have very safe thorium reactors both in fusion and radiothermic configurations that will fill the bill nicely. Might have to mine the thorium, build the reactors, and launch from the moon or mars to avoid the overseer class, but we have the tech since 1950 or so.
Musk better start buying up these start up rocket companies and add their unique ideas to spacex , if he wants to remain at the forfront of space development just as Microsoft did with its operating platform. Or later, he might have to get permission from one of these space companies to land on Mars at their spaceport already there.
Serious competition could come from Europe if it gets motivated and streamlines bureaucracy. We expect serious competition from Chinese and Russian nuclear projects if they can get a heavy lift to get it into orbit. LM9 or Energia 2.
You can make a cool rocket but without improved propulsion it's no different than any other rocket. It can serve a different purpose like taking a lot of payload to LOE like starship. Or it can take less but make a straight shot for its objective like SLS. The problem with this rocket is that Elon is promising so much more without improving the thing that matters. To get to the moon he stated it would take eight refueling starship launches to get one starship to the moon fully fueled. this is where the problems begin. Now you're in the world of added costs and statistical analysis. where on average you're looking at a 4% to 10% failure rate for any rocket launch. For any mission beyond LOE you multiply that by eight for failure of starship missions due to refueling. One starship damages the launching pad on landing or blows up during lunch. The mission is scrapped until an investigation is done. And hopefully anything in low Earth orbit has the fuel to come back down to try again. So that's where I feel you will lose your human rating. now if any other rocket if you block build you save money. the more you build at once the less they will cost like most items. I don't see how that's going to be true for starship. Their launch cadence goal is far beyond any other rocket provider. they want to produce 100 starships a year to deliver 1Mt to orbit per year. Including the flights of the refueling starships that 800 flights a year to deliver 1Mt to the moon. with a 10 year goal of 1000 starships to deliver 100 Mt a year. Which means in 10 years if their successful they would nearly triple the United States natural gas need. We don't even make 100% of our natural gas now. Also remember they were already delayed launches due to covid with Lox production. So then you run into the problem of fuel becoming more scarce and exceedingly expensive. It's the same problem that electric cars have. They sell you on improving the environment but what they're actually doing is displacing the problem without solving it. until the develop better propulsion which is a monumented asking of course. Starship is better off feeling a much-needed niche of rocket which we no longer have. Populating Mars is just not a realistic goal for everything that will be needed to sustain life. now if you want to look into a real innovation of rocket propulsion look up the saltwater nuclear rocket. It was a paper published years ago but very promising. Because there is no displacement in its capabilities and every aspect of the rocket has already been developed and proven. All that would need to be done is culminating and assembly of these different technologies to test and further develop. now you would not ignite this rocket in an atmosphere but in space it could get a fully fueled starship to Jupiter and back in six months according to the numbers. Now space X with starship will be in the unique situation to develop such hardware since testing in space would be preferable/required because what comes out the other end isn't exactly all that healthy. So my hopes rest in a small but functional starship fleet. That can act as or develop an Earth orbit or moon research facilities to develop items such as the nuclear saltwater rocket. But on its own the starship system I fear will fulfill as many promises as Tesla full self driving does today.
But I love self driving CornBread! (Love cornbread too... southern raised). We do need a better way to do it but for now this is the best we have. NTR is the only long term solution right now.
Of course they are going to say it can be scaled up, no problem as this first engine is very small in thrust, nearly useless, at 2 tons of thrust. But scaling up always fights the 3/2 power law, which is unavoidable. Sounds very, very doubtful that it can be scaled up to any useful degree.
Nope... the 3/2 power law does not apply to aerospikes... its 1/1... the extra heat can be recouped and used to power the turbines in any size of expander cycle engine... Even 3MN.
A big congratulations to Pangea! I’ve always loved the Aerospike engine and always believed attempts to perfect it should never stop. Thank goodness for never stopping.
We agree completely! No good idea should ever die!
Happy to finally see something about Relativity!
Siempre fi.
Semper fi Queefy! Relativity is awesome. We did an entire lesson on them once... we'll need to update it soon.
Thanx Sire,for yet another brilliant lecture..and Congrats Pangea Aerospace..fantastic achievement!
You are most welcome Dave! It is a great time to love rocket science.
Can't waiting till my children are graduating from an actual Terran Academy. Every episode is a university level lecture. I had never heard of grcop alloys. Thank you for all of your research and smart work.
Thank you Steven, we are very happy to hear you say that. :-)
Everyday Astronaut's thoroughly researched aerospike engine video is a must watch on this topic.
Good point Helix... We have watched it... and it is an excellent assessment of previous attempts at aerospikes. He did not of course address advanced alloys or this engine... which did not exist when he made the video.
@@terranspaceacademy The vacuum performance advantages hadn't really stuck in my mind till now. Thank you for this excellent update on the technology!
Another gem amongst the sea of internet dross - thank you! A very enjoyable and informative presentation as ever!
Thank you Stuart! We appreciate you!
I actually understood this video, very well done 👍. Not too much tech details so as to swamp a lay person like me, good job.
Glad it was helpful Steven! We try to balance providing an overview that is clear and concise with enough technical details for those more interested in the data and details. I am a also big picture person, but often force myself to go through the calculations so I can compare and fully understand different systems.
Thank you, a refreshing Chanel in these times of warmongering.
You are most welcome, these are indeed dark times.
Wonderfully presenting another giant leap for mankind.
Thank you Sir Jeffrey!
Serious congrats to Pangea Aerospace! Thanks TSA :)
You are most welcome Ken!
Amazing work by Pangea, and thank you for the video. Now that it has been shown to be possible, the floodgates will open.
Perhaps Blue Origin could swap an aerospike in place of their combustion chamber to solve instability problems.
I'm sure SpaceX will be watching too, and most of the small outfits like RocketLab, as the efficiency and comparative simplicity of the build must offer real benefits.
Great that NASA has promulgated the groundwork too.
We have high hopes for them :-)
Happy Thanksgiving to all my fellow space nerds
🎉
This channel is everything I ever wanted in this area of study and r&d.
We are very happy to hear that!
This was filled with so much good info! Thank You!!
So glad it was helpful Chris! Thank you for your feedback!
Great episode!! Very exciting technology. Keep up the great work!
Thank you Clem!
Great job explaining this.
Glad it was helpful!
Good hearing you again Captain!
Thank you Sal!
Dude I'm video 3 just found this channel and I'm hooked
Thank you EvryDay!
you are excellent!
i support you
love love love
Thank you so much Adam!
impressive, key take away the improvement and implementation of material science. Thermal management of aerospike has always been its downfall. 3D printing is proving to be gamechanger on so many fronts. I would love to see someone like Elon take this material break through and run the distance on this engine. Not requiring sea level or vacuum optimised variants is already such a mass benefit. I would really love to see the ISP, even if 20-30 lower than others it is going to revolutionise.
Nice work
Thank you Daniel!
Aerospikes do have the disadvantage that by the time you would be switching to a different engine, you'll want to drop an empty fuel tank for optimization anyways- this undermines the advantage of an engine that adapts to altitude, especially since aerospikes don't operate as efficiently as a conventional engine optimized for where it's at.
Another excellent inspiring presentation. As a retired engineer my gut tells me Aerospike will prevail until some brilliant physicist defeats gravity somehow in the not so distant future.
We dream of that day Steve! SUV to orbit like we see on Star Trek! Gravity has been such a pain.
I recommended Everyday Astronaut incase you had not watched the aerospike videos. Glad to see that you very much do your research. Nice video!
Did you see his latest on the Soviet rocket engine family? I thought I was detail heavy! Wonderful episode.
Another fantastic video. Great to see someone doing real research on the topic than believing what's printed in the press release.
Much appreciated Jodie!
Very well explained and engaging video . I get it
Glad it was helpful Ged!
The two stage Astro clipper video, perfect.
Thank you!
Wow.........the possibilities. 👏
Indeed! We are looking forward to finding out more.
I've always been a fan of Aerospike engines... thermal issues have been the big bugaboo, but there are some other issues like reaction efficiency due to the non-existent reaction chamber. Overall, I'm glad they are being given a REAL tryout!!
We are too! They might tap out at a certain size but then you just use multiple...
Ace , amazing what they did with such low budget
Lots of thought went into that print I have no doubt!
Hi from Spain
Ola Juan! I bet the weather there is as beautiful as the architecture! Very happy to hear from you.
Thanks for the video. I don't normally have the attention span for 20+ min vids, but I'll make an exception for yours. The GRCop-42 could have application for the flow path liners of scramjet engines. When we tested workhorse NASP scramjet combustors in the early 90's at GASL we used Narloy-Z. It was too heavy for flightweight hardware. Integral coolant passages would have been impossibly expensive at that time.
That's a very good point Tony... and with hypersonic back in priority I have no doubt it will find use.
Do we have any data yet about the engines performance? Isp would be nice
Yes
We have an email in to them but haven't heard back...
Hello, excellent videos.
Do you know which software language is being used by these new startup Space companies?
I have to write our engine control software, but which language?
Thanks for the videos full of inspiration.
Douglas Ray Renzoni CTO
You are most welcome Douglas. Python and C++ for most everyone. SpaceX uses LabVIEW for most of their systems is my understanding.
Yes, it's amazing that a small European startup achieves this state-of-the-art "Aerospike" engine. It's unbelievable that Nasa didn't persist in such an amazing technology. This Spanish Aerospace company - Pangea - made history. What next? European SpaceX fan.
There is nothing Elon is doing that other's cannot do. There is no reason why Europe cannot build something to rival Starship. French and German engineering are some of the best on Earth. Most cruise ships and yachts are built in Europe. Elon might be showing the way but soon many more nations will follow.
@@terranspaceacademy 14:50 This is very flawed economic theory. The government creates no wealth, hence the 70k EUR was extracted from another part of the economy, preventing private investments, which for all we know could have been in space technology.
Moreover, you're only presenting one example that you consider a success. You're not seeing all the other government investments which were also extracted from somewhere in the private economy and did not lead to anything useful (or worse, were invested in programs that reduce economic growth, e.g. trade restrictions).
@@terranspaceacademy Spanish engineering is proving to be good too
@@phamnuwen9442 Very high risk investment such as this initial Euro 70K does not generally provide the security to the average investor, nor allow for the original motivators to retain active control of the company and its R&D direction. Thus finding monies to carry a project forward is often prohibitive. OTOH govt investment from an array of financial and R&D packages allows for the potential spin-offs, retention of talent and resources, plus the downstream potential for tax and FX revenue plus employment. I had resigned as director of one promising R&D company due to the duplicity of its finance director trying to maximise his return, long before the company had 'legitimately' achieved its goals. His share of the company also diverted priorities away from R&D into posturing. Thus an excellent innovation is now rusting away somewhere in Holland.
SpaceX needs to buy this company. ASAP.
Come on no we need in spain to develop more aerospace industry xd
Or at least license the technology :-) SpaceX has an incredible number of 3D powder printers.
We think Europe should start working on a true spaceship. Something that would fit in the Starship fairing and work well for space exploration :-)
I always suspected that the issues of TWR with the XRS-2200 and J2 derived aerospike were that they were using the plumbing and turbomachinery of dedicated deleval bell engines, and not a fundamental design flaw of the Aerospike engine. It's a good step towards the rotating detonation aerospike which I think is pretty close to the pinnacle of bipropellant LPREs.
It would be indeed... the manufacturing techniques/AM had to exist before the aerospike was possible... then with GRCop-42 and similar alloys in an expander cycle engine heat is a good thing :-)
btw... Thanks, great stuff.
Glad you enjoyed it!
It seems to me that the problem of heating is a possible advantage using the expander cycle engines
It is indeed Mike :-)
Great lesson! Years ago, I had some beryllium copper tools I got at a flea market...I was told they were used around flammable gasses...strong as steel, and won't make sparks.
Nickel and chrome is the resistance wire for heating elements..gets hot, won't sag. It's the glowing strips in your toaster.
I agree wholeheartedly that 3D printing is the future of manufacturing...space and otherwise ..
I did not know the toaster wires were nickel and chrome but it makes sense! Makes you wonder what alloys we can make once we get really rare metals like osmium and iridium in larger quantities from metallic asteroids and psyche :-)
@@terranspaceacademy It's sold as " Nichrome" and has been around for decades .
In the past, you could buy it at hardware stores..it was sold by watts per inch...back when appliances were meant to be repaired.
Psyche 16 is supposed to be a treasure trove of rare metals ..
Beryllium powder may be poisonous. Berylliosis! it seemed to have been used in the 1st Nuclear Age at Oak Ridge National Lab with their Molten Salt Reactor Experiment MSRE the reactor was built with Hastelloy-N, thermally annealed.
@@konradcomrade4845 Beryllium is used as neutron multiplier in nuclear applications.
Wow... again another excellent video discussing a number of subtopics that build into a breakthrough in Aerospike engine development.
Interesting discussion on Copper... one more of the many uses of copper that I've heard throughout my life... Like ... my copper integrated socks I got while in AFG, which helped keep my feet cooler in my combat boots, must've took advantage of copper in a way to handle heat like those rocket engines at a lower level ... LOL Man, I could use a black version of those for work now ... Santa did you hear that?
Next the 3D printing will change a lot of things not only for space but like in the military with part making forward on the battlefield than shipping it from a factory on the other side of the world. Why carry massive tool sets with specially tools when you can have your basic set and print when as needed for special ones... forward operating 3D printers will change the future from the old days.
Again, thanks for teaching this old dog something new!!!
Thank you John! AM is indeed the way of the future!
5:55 GOD DA@M IT! That was my idea!
Great minds etc :-)
This turned out to be a very timely video, with the newly announced production problems with Raptor engines.
We thought so too...
Much simpler production...
Terran spae acedemy, can you send me the link to the white paper or source on the thrust/isp of the aerospike engine? i cant get the second additional information link to work
They are playing things close to the vest for now...
pangeaaerospace.com/propulsion/
the Isp of aerospikes has been best examined here...
scholar.afit.edu/cgi/viewcontent.cgi?article=2329&context=etd
though these are linear and we'll have to wait for Pangea to publish theirs..
@@terranspaceacademy where did you get the thrust from?
@@terranspaceacademy do you know what cycle the engine operates on?
Am I the only one who thinks the Pangea building looks like Stark Tower?
It does! I want an office there so bad!
I love what NASA does, they tried to make airospikes work and got close, but for reasons beyond their control were unable finish, so they got funding to work on the remaining problems and made their resaults available to others, they still get airospikes.
I am an Australian and I think it is fair to say that all countries admire, or in some cases envy NASA and their achievements.
I hope Pangea Aerospace succeeds, they deserve to.
I notice others on this thread suggesting that SpaceX's near future non-raptor engine may be an aerospike, I am thinking along the same lines, after all, Raptor is based on technology developed to a similar level that also did not previously fly.
We agree completely about NASA... on the shoulders of giants David. We are very proud of Pangea and wish them the best... we think there will be a rush on GRCop-42 and probably other variants, with 3D printers so advanced now I expect a paradigm shift and it would be great if SpaceX led the way.
I think it would be hard to do much better than Raptor for SpaceX's purposes with chemical rockets unless they went for an aerospike variant, which would also give a good reason for a name change.
And NASA is still getting the credit for funding cutting edge research that is only now paying off ! Wonder what research NASA is funding at the moment ?
I agree that there is a fair amount of money wasted at NASA, but this appears to be almost always the fault of politics, not NASA.
I would like to see Spacex develop Raptor2 alongside an aerospike version of raptor ( I am going to name this pet raptor Spike). One team on raptor2 and one on Spike should give a true comparison between the two, although to be fair to Spike he needs more development time to catch up.
Rockets built by private industry is hard. You have to put in a lot of money into infrastructure, into supplies, wages, land, permits and all of your first builds will blow up or fail. There are a lot of different technologies coming together (propulsion, electronics, materials, software, aerodynamics, avionics, etc)
I think that's why America is ahead with this still. Other nations must create red-tape free zones if they want a chance to succeed.
Well, hopefully NASA is sharing the material science info and other related knowledge with American companies. Do they license that info and just prevent them from creating weapons and sharing tech with other nations?
I would think that say a formula for making an optimized rocket nozzle, early rocket designs, aerodynamic studies and other things up to at least 1980 or 1990 should be available to citizens to get a jump on building a modern rocket. When we have this huge time lull of nothing new going into space, the old engineers retire and die. We need to keep passing on this knowledge.
I want to see what these guys that 3D print an entire rocket can do. Is SpaceX 3D printing any of the engine parts? I like that they're using a relatively cheap stainless for Starship. I'm hoping it is rapidly repeatable like they say it will be. I wonder if they could scale it down to make a next gen Falcon 9 for small payloads. Maybe just use 2 or 3 Raptor engines. And also make the Starship XXL as a tanker or heavy lift to get a crane, InSitu fuel generation plant and other big things to Mars and Moon.
Another gem. I put my production house in Barcelona at your disposal in case you want to make a followup piece on Pangea here.
When all this craziness is over and we can travel again we will take you up on that so fast!
"Greed has overcome greatness."
--Terran Space Academy
A sad state of affairs...
A bit of a misnomer, honestly. Without "greed" legacy space contractors wouldn't've been around and wouldn't've bothered to accept those big fat government checks to get Apollo done. To this day those same contractors still propose revolutionary architectures like ACES/XEUS, Mars Basecamp/MADV, or the innumerable advanced engine development programs that have been lead by NASA for the past four or five decades. The problem is, NASA has neither the funding nor the mandate from Congress to actually carry those projects out to completion, build vehicles with them, and make them useful to humanity. What's really wrong with the legacy space model now isn't really greed, it's government complacency and stingeyness. That's why the Rocket Labs and SpaceX's of the world have had to step up and try to fill those boots instead.
A footballer may be 'greedy' for wanting to score goals or touchdowns. There is much the same motivation in the financial markets, where the accumulation of wealth provides much the same emotional and status rewards, as well as presenting technical challenges and risk. The term greedy tends to be most generously applied by those who have achieved little, to those who over-achieve.
Thanks for an enlightening presentation. But at about 18:45 you stated that nothing will ever beat an aerospike for a chemical rocket in space. That is correct for the moment until someone comes up with an even better rocket design/material. We stand on the shoulders of giants and in the future others will stand upon our shoulders. Chemistry, physics, and mathematics grow and evolve. I do believe that there is more that we do not know than that which we do know.
I have no doubt you are right in general :-) much better things than chemical engines will be invented at some point. But aerospike engines optimize the energy produced by a chemical rocket. Like Elon saying the Raptor combustion cycle efficiency is less than 1% from perfect.
@@josephparker3033 That efficiency figure only holds if you can't escape the limits combustion place on energy gain. So if you could change the situation/limits you might be able to squeeze yet more energy out. In this case I've also actually heard of such a method via use of a detonation wave, which as such lets you exceed normal combustion energy returns, at the cost of now needing to control a rather dangerous phenomenon in your engine, detonation waves tend to like to detonate things after all. Still they've been working on that in for instance jet plane engines and apparently gained another 5% or so there in testing.
So if that holds for rocket engines as well, it might be possible to squeeze just a bit more efficiency still for a rocket.
That is true... a detonation engine uses the available propellant more efficiently to achieve a higher kinetic energy. Clear thinking Quickshot0!
just 3 futuristic words, I want to type in: Lofstrom Launch Loop
(kind of a continuous ballistic artillery, with excess kinetic energy recycling)
For planet earth maybe Aerospike is more feasible. For operations on the moon I think LLL would be quite an interesting alternative.
DED also has the advantage that the alloy can be made in the print head and the percentages of the constituent parts can be varied across the part so that each part of the structure can have a tuned alloy to meet it's specific requirements.
It does look like a most promising technology. Layering with multiple alloys would be very interesting.
Great video. But how do aerospike engines compare to rotating detonation engines?
Very good question. We won’t be able to truly know until they make one function as well as the Pangaea engine but the specific impulse should be better.
Nice presentation folks!
But can you put up some tech data here like overall mass of this engine and its volume; the thrust we already have ;) . Also shed some light on the way its feeding its fuel. In the test thers no turbopump visible. How does it work and what kind of cycle? Is an expansion cycle without preburner even with methalox possible due to that vast heat excess?
None of that is available yet I'm afraid. This is an innovative success and they are keeping things close to the vest for now. :-)
After seeing rocket engine engineering stagnate for decades with engines developed in the 1950s and 60s (ie: AJ-10, RL-10 & RD-107) still being used today as front line technology, I was overjoyed when SpaceX showed that it was possible advance the state of the art with a full flow staged combustion methane engine. Apparently inspired by SpaceX and NASA we are finally getting a workable Aerospike. Now if they could just get the SABRE is an air-breathing rocket engine to be practical.
The SABRE technology is sound... research funding is the problem. if they had put it in a fighter jet it would have all the funding it needed but none of us would hear about it for a long time.
_annular aerospike_
Great band name
🤣🤣
Don't tell Elon... he might have more kids...
Since there is no public data available about the actual ISP of those new engines, we have to be very couscous about their efficiency claims.
Especially in a vacuum all aerospace engines I could find data for, do lose out against well made comparable vac-nozzle engines.
It would be really interesting to see what data let you to the conclusion that aerospikes perform better in vacuum than conventional bell-engines.
An aerospike is in effect an infinite nozzle... something a de Laval nozzle cannot be... but in the end vacuum testing will need to prove the theory.
@@terranspaceacademy
An Aerospike is NOT an infinite nozzle.
First of all the spike has a finite length.
Secondly as the air pressure is going down with increasing altitude, the effect of the "virtual outer nozzle wall" becomes less and less useful. This increases vector losses, as the _outer exhaust_ gasses are not directed anymore. In vacuum they leave the nozzle at 90° to the flight vector. So in essence an aerospike engine is 100% underexpanding in a vacuum. The exhaust gases exiting the nozzle throat are directly hitting the vacuum without the chance of being "slowly" expanded by a bell nozzle.
An aerospike works "as if" it were an infinite nozzle...
I will differ to those who know more than me, and NASA...
who say the aerospike is much more efficient in vacuum than the bell nozzle.
"At low pressures, however, the nozzle operates in a "closed wake" state. Since the base is not subject to a high ambient pressure, there is no altitude compensation benefit, and the aerospike behaves like a high area ratio bell nozzle. Thus, in theory at least, the aerospike nozzle meets or exceeds the performance of the bell nozzle at all operating pressures."
"A way to visualize it is to imagine the gasses moving between two opposite walls which are coming closer to each other and then beginning to separate. At the point where the gasses have reached some low supersonic speed, one of the walls ends. This is the point where the external expansion ends. The other wall continues down and forms the spike contour. At the point where the other wall ends, the gasses expand around the edge of the wall. The amount of expansion is determined by the ambient pressure on the other side of the wall, the one which has ended. For details on the fluid process involved, look in any compressible flow textbook under the section on expansion fans and Prandtl-Meyer flow.(1)
This is the source of the altitude compensation. As the ambient pressure drops, the gasses make a sharper turn around the edge. As the gasses turn the pressure drops. The amount of turning is determined by the pressure difference between the combustion gasses just arriving at the edge, and the ambient air on the other side of the wall.
A good reference for this material is Modern Compressible Flow with Historical Perspective by Anderson.
HOW DOES IT WORK IN A VACUUM, WHEN THERE IS NO AIR PRESSURE TO CONSTRAIN THE EXHAUST?
The air flow around the aerospike nozzle exhaust is not what constrains the plume but rather the ambient pressure. Therefore, whether or not the nozzle is moving, the exhaust plume will be more or less the same (shear layer effects between the nozzle exhaust and the quiescent air being neglected, of course). In a vacuum there is no ambient pressure to constrain the exhaust plume and the turning angle of the plume will be (approximately) determined by Prantl-Meyer expansion wave theory.
A good reference for this material is Modern Compressible Flow with Historical Perspective by Anderson"
@@terranspaceacademy
Thanks! Interesting read.
Can you give me the link to the source?
I have to say I'm still skeptical about _"theory vs reality"_ here. Because if the Prantl-Meyer expansion waves were as good at directing the exhaust gases as a high area ratio bell nozzle, then all vacuum optimized nozzles would end just after the throat.
I know that tiny attitude thrusters for satellites are often cut off just after the throat. The losses of the gasses "rubbing" on the inside of the bell would offset any Isp gains from the expanding nozzle.
Can you place the printer in a noble chamber gas chamber to aid in eliminate the exposure to iron and oxygen? Possibly aiding the successful production of that alloy.
That's what he said. They use an Argon chamber.
:-) it must be expensive to handle... always in vacuum or Argon.
@@terranspaceacademy argon is cheap and easy to contain. Use it for welding stainless all the time.
You'll need a lot more than 21. The upper engine thrust vector will be outward. The net downward component needs to be a bit bigher than the vehicle weight. About a thord of the thrust will be wasted squeezing the vehicle.
Thank you for the feedback Rubik... I'm not sure I understand though... Squeezing the vehicle?
@@terranspaceacademy They don't face directly down. they face outward about 20-30 degrees from the rocket's long axis. Not all of the thrust force from each individual rocket is directly lifting. Picture the force vector of each individual rocket. about 30% of its force isn't lifting. its pushing sideways.
The US Navy used a concept on SLBM's to save space where the nozzle actually slides down and locks into place after it is ejected from the water and ignites onto a shorter nozzle and when it does it makes what is called a regular atmosphere nozzle. Why cant a similar system be used to extend the nozzle when the rocket starts reaching vacuum to turn it into a vacuum nozzle. The best way I can explain it is the plastic cups from the 70's that you could carry in your overnight bag that compact into a small disc. When you want to use it to drink you pull the plastic cup until it extends to make a cup. Same concept for the atmosphere to vacuum engine.
That is an excellent idea and has actually been used... on an RL-10 if I remember correctly but I could be wrong on which engine.
I would add ethanol to the list of suitable fuels for aerospike.
Regarding the heath-resisting alloys, the field of study has tired toward monocristalline nitride-free nickel alloys, as nitrogen weakens the bonds inside the alloy lattice. As the purification is achieved via a cooling profile, I don't know how printing fits into it...
Thanks for the great video...
Thank you! With aerospikes the heat conduction is vital... Copper and silver work best for that...
Is the 20kN a current limitation due to heat?
Not at all... just a first try... the engine should scale up very well.
I know everybody will pan this but I like the idea of those smaller rockets placed axially up each side of the lunar lander starship variant. Once the booster let's it go, they no longer need flamey end down or pointy end up. So a number of smaller engines on the sides could put it into orbit because there is so little atmospheric drag. It would just pitch nose over and blast up. This would allow the interior to be laid out with full length flat floors on 3 or 4 levels. Some of which could serve as tanks when needed or as habitable space other times. It allows for landing vertically in a horizontal position and use loading ramps to roll freight on and off, and easy access for personel. With smaller engines aiming a few degrees away from vertical they could be closer to the moon surface.
There it is, a mental toy to play with. Try not to ruin it. Lol
That is not a bad idea at all Dan :-)
One thing I've always wondered about Aerospike engines is how well they would perform with multiple engines next to one another. They rely on atmospheric pressure surrounding to provide a neutral expansion, but wouldn't there be severe issues with an uneven pressure surrounding the engines when they are arranged next to each other? My guess is this would cause vibration issues in the engine at minimum, even if it didn't affect efficiency or thrust. I'm not sure I've heard whether this would be an issue or not. It may be it doesn't matter, but I'm curious as to the implications. For a re-usable system you would have to have either multiple engines (so you can use just a few of them for landing when the ship is lighter) or have a very high level of throttleability on a few, or even one, engine. The latter makes any engine design more tricky and usually much more expensive. So right now it almost ensures you would have to have multiple such aerospikes on a re-usable system, even if it is a two stage one.
This is a great question... aerospikes will adjust to the outside pressure... this would include the pressure of nearby engines... the aerospike, by its nature, will adjust itself for different pressures on different sides. This should not transmit any force back the aerospike that I can see... but I will be happier when we has flown and we are sure :-)
Very i.pressive indeed!
Seriously hoping that this is what Elon Musk was reffering to when he said that he will need a new generation of engines beyond the raptor!
Wouldn't that be great! I was surprised they didn't say more.
Wouldn't it make sense to combine this aero spike tech and RDE with lower atmosphere air-breathing capability to make a commercially viable SSTO a reality?
Skylon is working on something like that...
How fast can it be made?
Aerospikes? They have a small one ready (20kN?) and are working on a bigger one... (300kN)
Starship needs a much faster pace or they will need to stay with what they have.
Never thought about that with 3D printing might be possible now especially with the Iconal alloys that have come out recently.
It's amazing that companies like Relativity could get a 3D file and print a Terran R with aerospikes!
Could this help solve SpaceX's Raptor production rate problem?
With enough printers... which I think SpaceX would make a better cheaper version and start selling... I have no doubt it would save time and resources while simplifying production.
The general public's standard or what constitutes proof is terrifyingly low and off target. That is probably the single biggest threat to civilization we face. The fallout of that touches every aspect of life negatively.
I am often confused by how tightly many in the general public will cling to a false belief while refusing to consider an accurate one.
Can the raptor engines be fitted with aerospike nozzles in a savings of weight and complexities?
We've looked at that... hard to do but not impossible. We were looking at a wider throat with a spherical obstruction and vanes to hold it in place tapering to an aerospike on the bottom. it might be better to just revamp the combustion chamber entirely though...
Is annular the best aerospike configuration ? Looks like linear would be the way to go now that the metallurgy is solved. That was NASA's original intent for the Delta Clipper.
We love linear aerospikes for several applications... the annular aerospike will probably scare your investors less :-)
It looks most like a "regular" rocket engine...
ULA might want to contact Pangea... BO seems to be late providing their engines.
We do love the Aerospike! And the people at Pangaea are wonderful.:-)
How do these temps compare to re-entry temps?
Good question! The average reentry temperature on the surface of a ship is about 1650K from absorbed photons coming from the shockwave (11,000K)... these engines burn much higher than that... it should be possible to actively cool a reentry ship as long as the heat is rejected out the engine.
@@terranspaceacademy is there a possibility to use new material as “heat shield” with scales, or to 3D print the hull and circulate a gas or insulate the air gap. I also noticed some material being added, like a coating, could that be added to the exterior of a structure as a heat shield?
Doesn't the concentric rings of engines around a central engine effectively accomplish what an aerospike does? With the gasses from the center engines making the inverted bell out of exhaust gasses.
With the engine layout of the starship booster for example. The center engine creates a plume that helps direct the next ring of engines. These engines could even be pointed towards the center at sea level and outwards at higher altitudes. Then again with the same on the outer ring of engines.
This of course wouldn't apply to single vacuum only engines. But doesn't it make them not worth the bother for multiple ascent engines.
Elon hinted that there is some aerospike like effect from doing that...
Thank you for the information. Can I recommend a little background music? The tone and cadence of your voice wants to put me to sleep, no insult intended.
You are not the only one to notice that David :-) I used to have it in the background but we had several complaints that it made it harder to hear the narration... we'll try to find a happy medium.
@@terranspaceacademy; I appreciate the reply. I imagine you'll find a clever solution. Best of wishes.
Well this seems like excellent news, yet another potential efficiency gain for future rockets. Though probably will take awhile to be fully tested out and possibly scaled to the power levels various companies might want. One wonders if SpaceX will take it in to consideration for a future complete redesign of the Raptor as well.
We were wondering the same thing... they've been unusually quiet about not-Raptor 2+...
@@terranspaceacademy Yeah, I'm not sure what to think of the suggested not-Raptor engine either. At the moment I can think of but three directions you can go in based on the statement made, a major redesign to increase reliability and reuse, which of course would be important. Trying to squeeze every last second of ISP of a radical new design you can to make the very tight margins not so constricting, like adding an aerospike and detonation engine concepts. Or truly go radical and consider something like a nuclear engine.
If I were to guess then the first or second seem more likely then the third at this time.
Spain is close to build an orbital rocket, check out pld space. Great video btw
Thank you! PLD space?
@@terranspaceacademy Yes
Sorry I didn't realize that you were already going there
No need to apologize... the expander cycle could limit rocket engine size but since the aerospike is a master at generating heat load we should be able to get a very large engine out of it :-)
Size is limited with expanders however stating with the liner Aerospike would allow for many and they would have to engineer the engine kinda backwards by trying to create as much heat as possible. Increasing fuel flow would take away more heat and optimizing the fuel oxidizer ratio would create more. Granted they could only take that aproach so far before they start running into all kinds of other problems
@@mikegonsalves11 That's right... it will need to be optimized as the deLaval nozzles have been ... but the potential is enormous!
I'm still hesitant as far as wild changes in current technology, but we are getting there.The exciting thing is technology isn't static. In a recent Tweet, Elon Musk said that the current Raptor will not be the engine in the final analysis. They are presently working on new technology which won't be called Raptor. Who knows what that might be.
We were shocked when he said that... the Raptor is so well refined at this point... it must be something revolutionary. Fingers crossed for aerospikes.
I'm late to the party, but heat is still the reason. With moden alloys, ya you could probably get something like a merlin powerhead to drive an areospike, it might even be a little better. But Rapor is on another level. Tested to 330 bar, made with those same modern alloys, and he is saying they are still having a hard time keeping the thing from burning up. With what was it, 4x the throat area? it's a currently unmanageable heat load. Raptor is going to outperform any areospike that's able to keep itself cool. That being said, Raptor is designed as super heavy engine. For a smaller orbital taxi application, sure. I have no idea how you believe 21 of those things is would be in any way better than 6 raptors. The plumbing alone would eat up your mass savings. You also can't can't use areospikes to land without orbital debris being kicked up. How would you propose mounting those in the side of the lander? Those won't be raptors either.
But the "new" (NASA came up with it in the 90s) alloy is truly revolutionary Corey. And you could coat with inconel or titanium for added strength... the heat actually becomes a blessing if you go expander cycle. We don't have large expander cycle engines because heat harvesting is limited in bell nozzles as size increases. This is not a problem for aerospikes. We could have a 3MN aerospike expander cycle engine. They would be mounted at a 15 degree angle to the vertical... 21 of them would have enough power and provide redundancy... just like 33 Raptors on SHB... and they won't kick up any more debris than a bell nozzle would...
@@terranspaceacademy Nozzles just fit better for a flush mount like the descent engines on Starship. Raptor is Full flow staged. Much higher chamber pressures than an expander cycle. Chamber pressure is where Raptor is getting its efficiency from. I hate to say it but if an aerospike could withstand that, Elon would at least made a prototype. Rocket Lab has a CEO that knows areospikes, and they are building a new lift vehicle right now. It's primary feature will be durability. So why no areospike? This copper alloy isn't exclusive, you think these companies aren't using it?
OH MY GOD GUYS ITS HAPPENING
We have little doubt it will fly :-)
See those stress tables, yet they are not very usefull without point of reference like stainless steel, high carbon ferrite(not sure if it can be used due to brittleness), inconel(well would eat budgets), copper for reference, even alloys of titanium.
That's a good point... The copper is not stronger than those metals... just stronger than pure copper and able to withstand the stress while still conducting sufficient heat to allow cooling...
I can't help but put on my psuedo engineer Kerbal hat on here and think about some what-ifs. So here goes- what if you could somehow get the TW ratio high enough to get it into the ball park of a Merlin engine? What-if the aerospike could be useful, not as an atmosphere optimized engine, but as a vacuum-optimized engine. Could there be an engineering path where an arrangement of nozzles could mimic an expansion ratio of over 500 with a relatively small nozzle making it much more compact than even a sea level engine? Since the aerospike engine uses several smaller engines, it should be able to throttle these engines for effective thrust vector control, no heavy hydraulics needed and a nice weight savings. Finally, lets throw in some rotating detonation engine tech with all of that and I would probably bankrupt SpaceX with all of these development projects. But what an engine that would be!
You are right on the money Brett... think of an array of these on the bottom of a large saucer shaped ship built on the Moon... then spin the saucer to get artificial gravity :-)
Hold on a second, who told you that an aerospike is tough or hasn't been researched? The Air Force fired the first liquid propellant aerospike in the late 50s, NASA experimented with them in the 60s (even planning and designing one based on the Apollo J2 to replace the Apollo J2) and both solid and liquid aerospikes have been tested multiple times in the last two decades. Yes the Starship, (should we ever see one actually built) would greatly benefit from an aerospike. Heck it would even do better with a standard plug-nozzle or even a plug-cluster since the Raptor doesn't have the needed throttling to handle landing well. Aerospikes were NOT "invented for SSTO's" they were initially studied for use in multi-stage rockets. In fact a type using what we call today a "Thrust Augmented Nozzle" was tested (and patented) by Aerojet in the early 1960s. The "plug" or blunt aerospike nozzle was in fact proposed and tested to be used at both a propulsion engine AND a heat-shield for reentry and recovery.
You also need to be clear that the LINEAR aerospike had issues BECAUSE it was a linear design. The NASA and Air Force round aerospikes, (and plug-cluster nozzle designs) had fewer cooling and mass issues. (A big part of the mass issue was in fact the mechanisms to allow gimbaling of the entire nozzle which was not actually planned to be required in the operational engine) Part of this was because the standard "plug" aerospike was (as noted above) also planned on being an actively cooled reentry heat shield so unlike the linear aerospike they had a much better and more effective cooling system. Plug-cluster engines use pretty much 'standard' rocket engines in cluster around the 'plug' and therefore also have a better cooling system.
"Hydrogen and methane" being the only propellants that can 'reasonably' be used to cool an aerospike engine again misses that aerospikes have been run on other propellants successfully up to and including solid propellant and an ablative 'aerospike'.
I understand that research into such things is actually more difficult today due to the vagaries of the internet but really this information IS out there and available. I need to ask if you've ever heard of a site called "Secret Projects"? (www.secretprojects.co.uk/) I'd recommend it for some basic research before you expend a lot of effort on some of these false premises.
Grats Pangea but they are FAR from the first here except in maybe 3D printing the engine. (And btw the earlier aerospikes were not built using 3D printing so that's another "opps" on your part, they can and have been built using more standard construction)
Thank you for your feedback Randy. This discussion started with why Starship would benefit from aerospike engines. This would mean liquid methane cooled. It is not our goal to discuss and argue everything that has ever been conceived. We try to keep the lesson length to something reasonable. The Pangea engine was never described as the first liquid cooled aerospike in concept... And linear aerospikes were discussed at length in another lesson with videos of the NASA tests. The point was that NASA had to stop their research for funding issues but was able to prove the metallurgy necessary for a 3D printable copper alloy that would be better than anything designed previously. This is not a false premise. It is a fact. Pangea was noted to be the first to build and test a functioning methane fuel aerospike. Methane is the rocket fuel of the future. It is not impossible to make aerospikes with other fuels, this has been discussed also. The point we made was that only methane and hydrogen can be used effectively in an EXPANDER cycle engine. In the end someone somewhere has usually thought of almost anything someone tries to do, or tried it and failed. Yes aerospikes have been built with other construction methods out of other materials, we made that clear. That does not change the fact that Pangea has succeeded where others have given up. If there are other companies with functioning aerospike engines in production and being ramped up to fly bring them to our attention please. Everyone makes mistakes. We are always willing to admit when we make an opps... did you mean "oops"?
See? Happens all the time...
@@terranspaceacademy
"We are always willing to admit when we make an opps... did you mean "oops"?
See? Happens all the time..."
Even with spell checking, far to often :)
"Thank you for your feedback Randy. It is not our goal to discuss and argue everything that has ever been conceived. We try to keep the lesson length to something reasonable."
I realize and appreciate that but your lesson gives a false impression which is why I spoke up.
"This discussion started with why Starship would benefit from aerospike engines."
Greatly and for a variety of reason you actually don't touch on but not all in the way presented.
For example the use of aerospike engines on the upper-portion of the Lunar Starship, (which are supposed to be pressure fed "mini-Raptors" that the Air Force paid SpaceX to develop but they never did) would be a disaster.
Specifically a "scarfed" nozzle set (ntrs.nasa.gov/api/citations/19900015790/downloads/19900015790.pdf) would be vastly better as it helps eliminate the heating from the engine plume which without a nozzle would require the skin around and below the engine exhaust to require active cooling itself. Using scarfed nozzles the section integrated with the skin will already have cooling channels built in.
Another example is aerospike engines on the Starship would eliminate the problematic and troublesome "engine bay" which consistently causes issues on every flight and is an all around (and well know to everyone but SpaceX it seems) "bad idea".
I'll note that it would also force SpaceX to finally invest in actually designing and building actual "landing legs" for the supposedly "reusable" Starship.
"This would mean liquid methane cooled"
Understood but you state that ONLY liquid hydrogen and liquid methane can cool an aerospike engine which is patently false. Which was my point.
"Methane is the rocket fuel of the future"
Arguable on all levels as it takes more steps to produce and is less efficient than liquid hydrogen despite that fuels operational issues. It has advantages but its current popularity is largely based on it's Terran availability as liquified natural gas.
"The point was that NASA had to stop their research for funding issues but was able to prove the metallurgy necessary for a 3D printable copper alloy that would be better than anything designed previously."
While there were funding issues if you read the reports the program had reached a point where it was going to be turned over to industry anyway. NASA does not "produce" its own products so that's the 'natural' process anyway. In fact those reports note that many rocket engines companies are looking to use this alloy in the future in the very form tested by NASA; As a 3D printed insert for conventional rocket engines.
"This is not a false premise."
I never said it was but there are many assumptions and statements in the lesson that reflect false premises on other areas. That's specifically what I was calling out.
"Pangea was noted to be the first to build and test a functioning methane fuel aerospike."
Yes but not the only one to build or test functioning liquid (or solid) propellant aerospikes and even fly them.
"Yes aerospikes have been built with other construction methods out of other materials, we made that clear. That does not change the fact that Pangea has succeeded where others have given up."
You assume that other companies 'gave up' simply because aerospikes are not in common use but that's a false premise right there. Pangea is building them because THEY want them. There is currently no 'market' for such an engine outside Pangea. Other makers of aerospike engines have found little interest in such engines and therefore have not produced them but that in no way equals them 'giving up'. Specifically most engine manufacturers have continued to research and improve the designs and Pangea has partaken of this knowledge and data base.
"If there are other companies with functioning aerospike engines in production and being ramped up to fly bring them to our attention please."
And that's called moving the goalposts :)
Has Pangea actually flown one of these functioning aerospike engines? If not then they are already behind several other startups and even NASA who actually have flown such engines. Ramped up? Again, why since there is no demand or market.
"Pangea wins" only because the criteria are selected so that only Pangea CAN win. (They have not yet won because they only PLAN on production and flight but have not done so yet so do not meet the criteria you post :) )
"The point we made was that only methane and hydrogen can be used effectively in an EXPANDER cycle engine."
False actually. ANY cryogenic propellant, (and yes that includes LOX as the Soviets tested a LOX expander cycle in the mid-60s) can in fact be used in an expander cycle. My personal "favorite" is cryogenic propane, (liquid propane cooled to LOX temperatures) which has about 80% of the efficiency of hydrolox but is dense enough to fit into the same space as RP1. (Meaning if used in something like the Falcon 9 upper stage you can have about twice the performance of RP1/LOX)
I'm all for trying to spread information about space flight and technology but it bugs me when I see heavily biased information that is also incorrect or misleading. We have enough of that from the likes of Musk and Zubrin who are seen as 'experts' on the entire subject by far to many people and who constantly show their lack of depth in either planning or knowledge which itself then spreads to the community.
Like I said I like your videos, (except for the heavy SpaceX/Musk bias but that's kind of endemic these days unfortunately) but I reach a point where I have to speak out and I thank you for listening and responding.
SpaceX needs to go up on the Stock Exchange. Millions around the world would invest.
But then the SEC swoops in and says.. "Mars!!" waste! fraud! abuse! No one expects the federal inquisition... :-)
Interesting video, though I’m not sure we can congratulate Pangea entirely, as it sounds like the alloy development and 3D printing research required to make it possible would never have happened without NASAs work and $$$$ (at least not yet) - leaving aerospike development at a dead end again.
You are quite right... That's why we in depth into NASA's and the Glenn Research Center's contributions instead of just saying... made of a copper alloy... like most of the news articles did :-)
would a steam-powered (or supercritical H2O ) linear aerospike be useful underneath Elon Musk's launch stand, just to blow away the exhaust gases in the first few seconds? it could also ameliorate the vertical sound waves, hitting the ground directly underneath the launch pad. I think the originally planned Water-Deluge system is not optimal, because it put additional resistance to the rocket gases at launch
Very interesting... create a suction type megavacuum effect? Very cool idea... it you could angle the aerospikes out at 30 degrees from horizontal or so...
Interesting engine protoype. But this video is about 90% longer than it needs to be.
Thank you very much Yutani :-)
It’s good to sometimes refresh the basics
👍👍
:-)
@@terranspaceacademy>>> I am currently rewatching this video.
I keep thinking your _voice_ sounds _familiar._
It then hit me why: You sound like actor Gil Gerard, who played the title character in the 1970s science fiction TV show *BUCK ROGERS IN THE 25TH CENTURY.*
{Really.}
Maybe they'll team up.
We hope so... hard work like that deserves recognition :-)
that's pretty tiny thrust. 20,000 newtons is only just over 2 metric tons. a raptor engine is about 225 tons and they are putting 31 of them on the first stage.
That's true Ron but this is the first device they tried to print. They will be able to scale up rapidly.
CAN SPACEX MOVE TO ANOTHER COUNTRY TO GET A REAL SPACE PORT GOING , IS IT GOING TO HAVE TOO ?
I think they should buy an uninhabited island in international waters and declare it an independent nation. Then they control their own spaceflight rules...
What? You mean ARCA's "Flight of the aerospike" series didn't come through? Say it isn't so.
With a specific impulse of around 200 seconds it was a hard sell with just h2o2 over a catalyst bed. Then they said they were going to turn thousands of liters of water instantly into steam with batteries... I had hopes but the tech isn't there.
Ummmm.... you forgot to tell your Ever Faithful Followers the Stock Ticker!!!! :-)
Private so far! We are watching that too :-)
I would love to see Elon musk integrate This into his rocket engine technology
I’m wondering about this third engine that will no longer be called Raptor :-)
Anyone have any ideas what it will be?
Congratulations on covering such a wide array of information, in sucjh a small time frame.
Your "exact" data, contained many errors. Still, you produced an amazing piece of information.
Of greatest note:
your continual references to only two of the space-able groups.
(there are more than 12 !)
Thank you Dirk! I'm not sure I ever refer to the information I glean as "exact" though... please send a detailed list of errors to terranspaceacademy@gmail.com and we'll be sure to do a correction burn and avoid repeating them.
Let SpaceX learn to fly their ship. Then they can improve.
It does not make sense currently to make it more complicated. Currently. Just for now.
Later they can improve it when it makes sense. They will improve it when it makes sense, of course they will.
I’m sure they will.
Well some have broken the laws of physics, but have had their lives threatened or work for the government under non disclosure agreement. I was going to throw this argument at you, my point being that without the suppression we would have had open anti gravity almost a century ago. Look into the work of Walter Bosley.
Interesting! We'll look him up.
I think ion engines with kilonewtons of thrust evolving to meganewtons will bee the following to chemical rockets, and probably before we get to mars. Lol
What power supply do you recommend?
Once we have fusion Dan :-) everything changes! Until then the best we could do would be chemical to orbit and nuclear to Mars, Mercury and beyond!
henry thorium in a LIFTR configuration.
@@terranspaceacademy we have very safe thorium reactors both in fusion and radiothermic configurations that will fill the bill nicely. Might have to mine the thorium, build the reactors, and launch from the moon or mars to avoid the overseer class, but we have the tech since 1950 or so.
Musk better start buying up these start up rocket companies and add their unique ideas to spacex , if he wants to remain at the forfront of space development just as Microsoft did with its operating platform. Or later, he might have to get permission from one of these space companies to land on Mars at their spaceport already there.
Serious competition could come from Europe if it gets motivated and streamlines bureaucracy. We expect serious competition from Chinese and Russian nuclear projects if they can get a heavy lift to get it into orbit. LM9 or Energia 2.
You can make a cool rocket but without improved propulsion it's no different than any other rocket. It can serve a different purpose like taking a lot of payload to LOE like starship. Or it can take less but make a straight shot for its objective like SLS. The problem with this rocket is that Elon is promising so much more without improving the thing that matters. To get to the moon he stated it would take eight refueling starship launches to get one starship to the moon fully fueled. this is where the problems begin. Now you're in the world of added costs and statistical analysis. where on average you're looking at a 4% to 10% failure rate for any rocket launch. For any mission beyond LOE you multiply that by eight for failure of starship missions due to refueling. One starship damages the launching pad on landing or blows up during lunch. The mission is scrapped until an investigation is done. And hopefully anything in low Earth orbit has the fuel to come back down to try again. So that's where I feel you will lose your human rating. now if any other rocket if you block build you save money. the more you build at once the less they will cost like most items. I don't see how that's going to be true for starship. Their launch cadence goal is far beyond any other rocket provider. they want to produce 100 starships a year to deliver 1Mt to orbit per year. Including the flights of the refueling starships that 800 flights a year to deliver 1Mt to the moon. with a 10 year goal of 1000 starships to deliver 100 Mt a year. Which means in 10 years if their successful they would nearly triple the United States natural gas need. We don't even make 100% of our natural gas now. Also remember they were already delayed launches due to covid with Lox production. So then you run into the problem of fuel becoming more scarce and exceedingly expensive. It's the same problem that electric cars have. They sell you on improving the environment but what they're actually doing is displacing the problem without solving it. until the develop better propulsion which is a monumented asking of course. Starship is better off feeling a much-needed niche of rocket which we no longer have. Populating Mars is just not a realistic goal for everything that will be needed to sustain life. now if you want to look into a real innovation of rocket propulsion look up the saltwater nuclear rocket. It was a paper published years ago but very promising. Because there is no displacement in its capabilities and every aspect of the rocket has already been developed and proven. All that would need to be done is culminating and assembly of these different technologies to test and further develop. now you would not ignite this rocket in an atmosphere but in space it could get a fully fueled starship to Jupiter and back in six months according to the numbers. Now space X with starship will be in the unique situation to develop such hardware since testing in space would be preferable/required because what comes out the other end isn't exactly all that healthy. So my hopes rest in a small but functional starship fleet. That can act as or develop an Earth orbit or moon research facilities to develop items such as the nuclear saltwater rocket. But on its own the starship system I fear will fulfill as many promises as Tesla full self driving does today.
But I love self driving CornBread! (Love cornbread too... southern raised). We do need a better way to do it but for now this is the best we have. NTR is the only long term solution right now.
Of course they are going to say it can be scaled up, no problem as this first engine is very small in thrust, nearly useless, at 2 tons of thrust. But scaling up always fights the 3/2 power law, which is unavoidable. Sounds very, very doubtful that it can be scaled up to any useful degree.
Nope... the 3/2 power law does not apply to aerospikes... its 1/1... the extra heat can be recouped and used to power the turbines in any size of expander cycle engine... Even 3MN.