Cool video, awesome to see you found the old SDSU video. I was one of the founding members back in 2003-2005. To shed a little more light on that last launch, which i consider a half success. We used old LR101 rocket motors, whch were used as side thrusters on the Atlas rocket. Since moat of these rocket motors had been sitting around for 50+ years before we used them, we cleaned them as best as we could. Our leading theory was that once the high pressure kerosene hit the cooling coils, it knocked off rust, which in turn clogged the injector plate. This in turn caused the engine to run oxygen rich, which was hot enough to burn thru the nozzle throat. When that happened kerosene was reintroduced back into the combustion, but this time outside the combustion chamber (I believe thats what you said). This caused unsymmetrical thrust ultimately arching the rocket into the ground like a lawn dart.
Right off the bat, I appreciate you breaking down WHAT failed. I've seen plenty of catastrophic launches but rarely hear what went wrong. Once you've gained that understanding then you can apply that every time.
Hi, former USC Rocket Propulsion Lab team historian here. This is a really cool video! It's nice to see some background on all the progress that rocket teams have made in the last decade or two, and all the setbacks that they've had to deal with. Anyway, couple minor things to note: 1. We believe that Traveler 1 actually failed due to an issue with the propellant mix -- a process step was missed which led to the outsides of the fuel grains beginning to burn during flight. This likely caused an exponential increase in pressure inside the motorcase, leading to kaboom. That said, we figured out in later launches and static fires that the case design used on this rocket was flawed as well, and there's a good chance it would have failed in another couple seconds anyway. 2. You're pretty much bang on correct about the Traveler 3 situation, I'm afraid. It was really a pileup of bad stuff: there was procedure chaos on launch day due to things like our trailer losing a wheel and putting us 12 hrs behind schedule, our igniter cable not being long enough to go from base camp to the pad, dust storms, etc. Then there was a radio miscommunication between the team at the ignition box and the avionics operators: we on avionics told them we were disarming it to check out a sensor reading, and they didn't hear us. Then they launched it, not realizing we weren't ready. Though in some ways that day was a success (first time we had an 8" full size vehicle not blow up), it was incredibly facepalm-worthy and we had to think long and hard about how to make sure it couldn't happen again. 3. The first two of the recent static fire failures were attributed to problems with the carbon fiber motor-case, yeah, but not to mistakes in manufacturing it. Rather, Earthshaker and Earshakiier used different carbon fiber designs that reduced the number of layers in an attempt to make the case lighter. After a ton of simulations and math, many tests with strain gauges, and two failed motors, we finally realized that the original Traveler 3/4 design was in fact better, though now we have a much better idea of what makes it work. For the third one, Earthshakiiest, we switched back to the original case design but tried a new propellant formulation, which turned out to have issues with cracking. We suspect that the propellant grains broke into pieces on ignition which caused a huge increase in burning rate and a big boom. All in all, thanks for making this video and glad to see my team get some love!
Thanks for the super detailed information. I feel like I should consult you before anything I say about USCRPL in the future :). Tbh, your team has inspired many teams throughout the world with your past successes and even inspired the formation of ASTRA Bremen. So, it is really cool to learn more about the history and details of your challenges. We are all looking forward to what USCRPL has in store for the future!
I’m way late to comment here, but for the radio miscommunication issue: seems like launch control should poll all other entities prior to final 60-sec countdown to launch. If they don’t get an acknowledgment from one of them, it’s a no-go. Ask again and if still no response, go into a hold or scrub, whichever is needed. Not launch on the assumption that silence means approval. 🙂. Just my thought. Maybe you already decided that.
I remember very well seeing Aris launch teil rocket Euler at EuRoC 2021. Unfortunately their solid motor (which actually was COTS!) started spewing flames from both ends, and ended up being quite a spetacular failiure.
The most powerful F class motors will give you somewhere between 10-20 N of thrust depending on the type. Lets be generous and say you get a really short burning one that gives you 20N. The Reliant at the end of the video weighs roughly 500kg, so it takes around 5000N of thrust to make it lift off vertically. That means you will need at least 250 of those motors to get it off the ground... To have it actually take off a bit and fly in an arc of some magnitude you probably will want at least 2g of acceleration at the start so that at least doubles the required motors to 500+! If you try to buy that many at once, you might get put onto a special list...
Dude should look up the difference between a propellant and an explosive... In the model rocket community an explosion is called a CATO where in the propellant catastrophically explodes.
They should have drop-tested their car first from a helicopter in forward flight from 8,000 feet. But that’s expensive, too, and probably requires some sort of FAA waiver. I suspect it was more for spectacle and they didn’t really expect it to be controllable in flight. 😄. It was pretty awesome, though. Seems like it might have been easier to build a plywood 1/8th-scale model of the shuttle orbiter, radio controlled.
When Flanges can not survive 3.000Celius Heat, why not make this into some sort of Screw and holt it with this many bolts 4:23 ? What if, someone invent some Spin or Vibrations shock absorber. So the Engine Section can Vibrate all it needs and the Upper Section, perhaps with the Stability Fins stay calm
The purpose of the fins is to push the center of pressure behind the center of mass. This is needed for stable flight. Placing the fins toward the front of the rocket would do the opposite of this and make the center of pressure in front of the center of mass; thereby actually destabilizing the rocket.
There was a time when people with your habit would have their tongues tied behind their backs to keep them from compulsively phonating at night in bed. Some boys accused of excessive phonating were even lobotomized for it. Fortunately the world grew up and accepted that phonating is completely normal and natural. However asking the host to phonate for you is unacceptable. ;-P Seriously, I didn't miss a word he said.
@@karlharvymarx2650 To _phonate_ is to speak out clearly. As far as you go, you seem to be satisfied with people who don't speak clearly; with language being one of the things that separates us from the lower order animals... _" tongues tied behind the back"; " compulsively phonating at night in bed";_ you make no sense. Furthermore I'll give advice if damn well please. If I hear somebody in a public forum, which is what RUclips is, and I hear them not communicating well - in this case rushing and slurring their speech, then I'll say something about it. If you don't like it, tough. Cope.
@@davidvaughn7752 Hint 1: Awkward rhyme. Hint 2: ruclips.net/video/nrTX8A7ut7A/видео.html Will hopefully fill in some more blanks. If going ape shit still seems like the appropriate response, I suggest a crate of warm banana skins, case of Kleenex and doing your best to really piss off Mr Corn Flake because you seem a bit tense.
1) There is no such term as "solid rocket". Perhaps you want to say "solid fuel" rocket. 2) Your frequency vs roll graph is wrong: the rocket's natural frequency doesn't change. And many other errors in your script. You might want to make sure you really know the terms, where and how they apply, otherwise you'll be misguiding people.
Cool video, awesome to see you found the old SDSU video. I was one of the founding members back in 2003-2005. To shed a little more light on that last launch, which i consider a half success. We used old LR101 rocket motors, whch were used as side thrusters on the Atlas rocket. Since moat of these rocket motors had been sitting around for 50+ years before we used them, we cleaned them as best as we could. Our leading theory was that once the high pressure kerosene hit the cooling coils, it knocked off rust, which in turn clogged the injector plate. This in turn caused the engine to run oxygen rich, which was hot enough to burn thru the nozzle throat. When that happened kerosene was reintroduced back into the combustion, but this time outside the combustion chamber (I believe thats what you said). This caused unsymmetrical thrust ultimately arching the rocket into the ground like a lawn dart.
Right off the bat, I appreciate you breaking down WHAT failed. I've seen plenty of catastrophic launches but rarely hear what went wrong. Once you've gained that understanding then you can apply that every time.
Hi, former USC Rocket Propulsion Lab team historian here. This is a really cool video! It's nice to see some background on all the progress that rocket teams have made in the last decade or two, and all the setbacks that they've had to deal with. Anyway, couple minor things to note:
1. We believe that Traveler 1 actually failed due to an issue with the propellant mix -- a process step was missed which led to the outsides of the fuel grains beginning to burn during flight. This likely caused an exponential increase in pressure inside the motorcase, leading to kaboom. That said, we figured out in later launches and static fires that the case design used on this rocket was flawed as well, and there's a good chance it would have failed in another couple seconds anyway.
2. You're pretty much bang on correct about the Traveler 3 situation, I'm afraid. It was really a pileup of bad stuff: there was procedure chaos on launch day due to things like our trailer losing a wheel and putting us 12 hrs behind schedule, our igniter cable not being long enough to go from base camp to the pad, dust storms, etc. Then there was a radio miscommunication between the team at the ignition box and the avionics operators: we on avionics told them we were disarming it to check out a sensor reading, and they didn't hear us. Then they launched it, not realizing we weren't ready. Though in some ways that day was a success (first time we had an 8" full size vehicle not blow up), it was incredibly facepalm-worthy and we had to think long and hard about how to make sure it couldn't happen again.
3. The first two of the recent static fire failures were attributed to problems with the carbon fiber motor-case, yeah, but not to mistakes in manufacturing it. Rather, Earthshaker and Earshakiier used different carbon fiber designs that reduced the number of layers in an attempt to make the case lighter. After a ton of simulations and math, many tests with strain gauges, and two failed motors, we finally realized that the original Traveler 3/4 design was in fact better, though now we have a much better idea of what makes it work. For the third one, Earthshakiiest, we switched back to the original case design but tried a new propellant formulation, which turned out to have issues with cracking. We suspect that the propellant grains broke into pieces on ignition which caused a huge increase in burning rate and a big boom.
All in all, thanks for making this video and glad to see my team get some love!
Thanks for the super detailed information. I feel like I should consult you before anything I say about USCRPL in the future :). Tbh, your team has inspired many teams throughout the world with your past successes and even inspired the formation of ASTRA Bremen. So, it is really cool to learn more about the history and details of your challenges. We are all looking forward to what USCRPL has in store for the future!
I’m way late to comment here, but for the radio miscommunication issue: seems like launch control should poll all other entities prior to final 60-sec countdown to launch. If they don’t get an acknowledgment from one of them, it’s a no-go. Ask again and if still no response, go into a hold or scrub, whichever is needed. Not launch on the assumption that silence means approval. 🙂. Just my thought. Maybe you already decided that.
Love the shout-out for Obsidian! (Also the rocket that failed was copperhead)
Cool to see these young engineers breaking through that glass ceiling of modern capabilities with innovating these new technologies!
I remember very well seeing Aris launch teil rocket Euler at EuRoC 2021. Unfortunately their solid motor (which actually was COTS!) started spewing flames from both ends, and ended up being quite a spetacular failiure.
Yikes! They have come a long way over the years. Their launch at the SA cup this year was spectacular (even though they overshot the 30k target).
I like you added bbc top gear rocket that was a cool episode
How many esties Rocket motors would be needed to lift a small car?
The most powerful F class motors will give you somewhere between 10-20 N of thrust depending on the type. Lets be generous and say you get a really short burning one that gives you 20N. The Reliant at the end of the video weighs roughly 500kg, so it takes around 5000N of thrust to make it lift off vertically. That means you will need at least 250 of those motors to get it off the ground... To have it actually take off a bit and fly in an arc of some magnitude you probably will want at least 2g of acceleration at the start so that at least doubles the required motors to 500+! If you try to buy that many at once, you might get put onto a special list...
The first rocket is cute
Am still waiting for the Biggest Explosions OOPS Sorry I just figured it out, you are a Clickbait Title Specialist.
I'm curious, how big an explosion were you expecting from *amateur* rocketry?
Dude should look up the difference between a propellant and an explosive... In the model rocket community an explosion is called a CATO where in the propellant catastrophically explodes.
Too much chat! UK
Fantastic video !!
Cool Explosions!
Ammmmm Mr. Manbun. NO EXPLOSIONS HAPPEN WHEN "EVERYTHING WAS DONE ABSOLUTLY RIGHT".
shit thats done absolutly right go 100% right.
Good stuff, though some work on narration & description may be beneficial. Why not show the actual impact of the Reliant?
They should have drop-tested their car first from a helicopter in forward flight from 8,000 feet. But that’s expensive, too, and probably requires some sort of FAA waiver. I suspect it was more for spectacle and they didn’t really expect it to be controllable in flight. 😄. It was pretty awesome, though.
Seems like it might have been easier to build a plywood 1/8th-scale model of the shuttle orbiter, radio controlled.
"Unscheduled Rapid Disassembly"
that rolling moment is a dutch roll that can happen to aircraft to.
Keep safe
Don't use stainless steel bolts for high strength applications, LOL. Wow, kind of a basic ME fail on that Balerion test.
When Flanges can not survive 3.000Celius Heat, why not make this into some sort of Screw and holt it with this many bolts 4:23 ? What if, someone invent some Spin or Vibrations shock absorber. So the Engine Section can Vibrate all it needs and the Upper Section, perhaps with the Stability Fins stay calm
Why are there never fins towards the front of rockets ? Wouldn't this help with stabilization?
The purpose of the fins is to push the center of pressure behind the center of mass. This is needed for stable flight. Placing the fins toward the front of the rocket would do the opposite of this and make the center of pressure in front of the center of mass; thereby actually destabilizing the rocket.
@@ASTRABremen I really thank you for the explanations.
Sweet unibrow bro
what about it
there are no failures, only data
Where in the world is carbon San Diego?
One day Carmen San Diego will no longer be on 🌎 😢
Whats a kilometer do you mean mile
Lots of “actually”, but no big explosions.
Whats a kelvin
biggest explosions?? where? maybe some fubars but not really explosions...
would be better if you could Speake more consisely
I am good.
15 minutes in and only a minor pop no explosion yet
talk only ! not create
5 minutes in and no explosion
Whats a meter? Do you mean feet?
click bait
Slow down and _phonate_... we know you're excited but we'd also like to hear what you have to say!
There was a time when people with your habit would have their tongues tied behind their backs to keep them from compulsively phonating at night in bed. Some boys accused of excessive phonating were even lobotomized for it. Fortunately the world grew up and accepted that phonating is completely normal and natural. However asking the host to phonate for you is unacceptable. ;-P Seriously, I didn't miss a word he said.
@@karlharvymarx2650 To _phonate_ is to speak out clearly. As far as you go, you seem to be satisfied with people who don't speak clearly; with language being one of the things that separates us from the lower order animals... _" tongues tied behind the back"; " compulsively phonating at night in bed";_ you make no sense. Furthermore I'll give advice if damn well please. If I hear somebody in a public forum, which is what RUclips is, and I hear them not communicating well - in this case rushing and slurring their speech, then I'll say something about it. If you don't like it, tough. Cope.
@@davidvaughn7752 Hint 1: Awkward rhyme.
Hint 2: ruclips.net/video/nrTX8A7ut7A/видео.html Will hopefully fill in some more blanks.
If going ape shit still seems like the appropriate response, I suggest a crate of warm banana skins, case of Kleenex and doing your best to really piss off Mr Corn Flake because you seem a bit tense.
You talk too much (bla, bla, bla) for poor content
Yawn….. Waste of time. Nothing to see here.
Yawn
1) There is no such term as "solid rocket". Perhaps you want to say "solid fuel" rocket. 2) Your frequency vs roll graph is wrong: the rocket's natural frequency doesn't change. And many other errors in your script. You might want to make sure you really know the terms, where and how they apply, otherwise you'll be misguiding people.
Lies and click bait.
how?
😠CLICK BAIT😠
Why did I watch this? Searching for rocket explosions. Few and far between, and not very spectacular.
Actually,actually actually I think you show your face tooooo much, are you in love with yourself?