As an airline pilot, I applaud your very accurate description of what happened on this aircraft. Proper analysis, proper terminology, and simple enough for a non-engineer to understand. The big bonus here is the opportunity to teach physics, chemistry and engineering with the story as a background. Well done!
Largely correct but one point of note, even if you don't have "fly by wire" flight controls you still need a RAT. The 767, CRJ, and E145 I've flown all have RAT's and are not fly by wire. Reason being at a speed of .84 mach there's not enough mechanical force from both pilots put together to be able to move any of the primary flight controls. Simply too much air resistance. RAT's can either be an additional electrical generator or a hydraulic pump directly powering the PCU (power control unit) that the cables hook to that move the flight controls. Hope this cleared something up, overall excellent video!
I love how you so much love the technology you talk about, I can see in your face how much passion you have, I've been an electrical fitter for almost 50 years, I build control panels from scratch and after all these years I still love my job, great videos
as an engineer myself I fully understand the conservation of energy you demonstrated. sometimes when you instinctively understand things you tend to gloss over important details parts when explaining them to others. I commend you Jeremy, for putting together a vary concise, complete and understandable demonstration. well done!
Off on a Tangent: A person I worked with for years was on that flight. There was of course a class action suit launched by the passengers after this. They reached a settlement nearing $ 50 million Cdn. Out of that, the legal team received nearly half. While that sounds outrageous, these kinds of suits demand huge time in research, and payment of expert witnesses. The rest of the money was divided in terms of more money going to passengers who were injured using the emergency slides. A broken ankle on an elderly person, for example, can lead to substantial loss of quality of life. My co-worker friend suffered no injuries, and was stoic enough not to mention the nightmares and such. At the end of everything, he realized $ 8000.00 Cdn. Basically made whole on his expenses, and not much else. So when you hear of these big settlements, don't assume that the plaintiffs are making out like bandits.
@@fromthepeanutgallery1084 yep, it seems like no matter what the story is, the lawyers always seem to be the ones who get the lions share, I don't care how much effort they went to, it can't be more deserving than some innocent person who goes through hell and may also be damaged for life...
@@fromthepeanutgallery1084 Well, I don't know. It's easy to cast aspersions on lawyers in general. It does seem like a rather generous pay day, but we don't know the expense side of the ledger. I'm not sure what civil and criminal lawyers are currently charging per hour in court, but last I saw it seemed rather exorbitant, and I doubt the hourly rate has gone down since. In Canada police and the Crown Attorney's are pretty corrupt when it comes to looking the other way when the wealthy/connected or corporate abuse the public, so I'm inclined to cut Civil Litigators a bit of slack seeing that they are about the only path to justice in these kinds of matters.
@@rodchallis8031If the only path to justice costs $600/hr, it effectively means there is no justice for normal people. Not sure if it's ever been different though.
@jonahwhale9047 Why would the crew/engineers get a reward? Firstly they're not the plaintiffs, second they are just doing their job and on top of that the pilots neglected to check the checklist when they noticed lower than expected fuel which potentially made the incident much worse than it needed to be.
Amazing story and amazing job explaining it to a noob like me. As someone who occasionally flies for work, when you described the cabin lights going out and the second engine shutting down (and the ensuing silence) I literally felt sick. I could imagine how tense and worried I’d be. Great video.
This is one of my favourite air "disasters". Your explanation of conservation of energy reminded me of a few months I bought my 2000 Honda Insight. Was filling up and a guy at the fuel station told me I should put a windmill on the front of the car attached to a generator to charge the batteries. That way, it would recharge as I drove and I'd never have to buy fuel again! I tried to explain that "in this house we obey the laws of thermodynamics" but his suggestion was to just use a large windmill! Finally after going around in circles a few times I told him that he was a genius with a world changing idea so he should invent himself and make billions. I always wonder if that guy went home and started playing with oscillating fans in his garage.
Sadly for him, Kia were ahead of the game... the Kia Niro EV (and others) has a "Vehicle-to-Load" system. There is (dependent on country) a 230 volt, 16 amp power point inside the cabin. All you need to do is plug the charge-cable into the charge-point on the front of the car, feed the cable in through the window, and plug it into the Vehicle-to-Load socket... Now you can drive forever! (I don't know why Kia did not build the cable into the car, it is quite ugly, and you get cold in winter! Ahh well, small price to pay, I s'pose, maybe in next year's model.) WhaDaYa mean Jeremy... you're just confusing me with all this "Conservation of Energy" nonsense! 😠 Yeah... of course I know about thurma-dye-nam-ickxs! 😜
I clicked on this link and was happily surprised to see your face. I haven't seen your videos in a couple of years, despite the fact that I'm subscribed to your channel. Nice to see you again. Well done on the video.
An EXCELLENT video, Jeremy! I spent a lot of years doing or supporting aircraft maintenance, both in the military and for a major airline, so I was already familiar with what a ram-air-turbine (RAT) is and it's importance. What I particularly like is your engineering and physics based approach to the discussion. I hope you are inspiring lots of young people to pursue the STEM topics. Another interesting topic may be the "Gimli Glider" incident in Canada, several decades ago. A large passenger aircraft on a trans- continental flight ran out of fuel about halfway across. The complicating factor here is that Canada was in the middle of transitioning from the British Imperial measurement system to the Metric system, revenant documents were not updated, and more. One of the pilots knew the area, because he had served at a (closed) RCAF base nearby. That knowledge, and the RAT, resulted in a successful landing. I believe the aircraft was repaired and put back into service. At this point I would normally rant about the idiocy of the USA not making metric mandatory instead of just the current status of "legal". (The other two countries are each smaller than most US States.) But maybe that can be another video.
I naturally assume that your video is now an integral part of pilot and engineer training. The pilots will learn not to miss in their panic, that comment above the list, and stop the fuel from reaching the rupture.
The universe was not built upon Metric, and it is an inferior, less precise McGuffin of a hubristic scientism rampant among the over-educated, and congruently less clever.
Jeremy following you in Rwanda, well done your lectures are helpful to us, in developing our minds on those complicated issue due to unperfect explanation we did got in past
As usual you managed again to explain an issue in a simple way but to the core. Like my late father who was a pilot, instructor and examiner for technicians told me, "Its not hard to explain things in a complex way, but to explain things in a simple way you must really understand and know what you are talking about."
This video is such an incredible lesson by using an emotionally engaging story to mentally step through the engineering process of designing a well balanced and practical machine with just enough emergency gear! ❤
Your explanation of ram air turbine physics made me interested in the energy absorption. After a quick Google, I found out that windmills do indeed attenuate wind speed. Apparently you can lose up to 80% of the output by spacing them closely in a wind farm. Interesting.
I've been shot at and I've done other things, but to this day the proudest thing I've done was fixing 5 different engine generator problems while in the middle of the ocean between the UK and Iceland. As an electrician flying on a C-130 on our way back home after picking up the aircraft from Bagram AFB, I was of course woken up mid flight to see what I could do. The first time I was woken up we had lost 2 of the 4 main generators and the corresponding electrical busses didn't automatically swap over to the remaining generators to prevent power disruption. This alone is extremely unusual, there are 4 main electrical distribution busses that are connected to main engine generators by 8 contactor rated for 210vAC @ 400hz and 300 Amps. The contactors are arrange in a way where they are automatically energized and de-energized by the generators themselves to switch power between the main bus so no one generator accidentally tries to turn a different generator into a motor. Once all 4 engines and generators are up you can technically loose 4 of the 8 contactors with out getting a single warning and with out loosing a single distribution bus, under highly specific and perfect conditions. Prior to this event the only time i had ever seen two generators go out at once, where the busses also didn't automatically kick over. It was on a C-130 we had just taken out of the bone yard and where preparing it to be flyable again. After the 3 function test flight the aircraft's crew called down with an in flight emergency. When I examined the system some 4awg wires had chaffed each other's multi layered insulations that include fiberglass wrappings and some polymers that give you cancer if you simply pronounce the name of the molecule chain. Needless to say there where lots of scorch marks. As I remembered that incident I checked the fault codes but they where generic and usually fixed by a power cycle while on the ground but obviously we were not on the ground. I also, sniffed around for some magic smoke but nothing. As we where somewhere between the UK and Iceland and still had some power, I had the crew turn off the two faulted generators. I pulled all the circuit breakers for the two generators and then started to remove the paneling for the contactors to make sure nothing was going. Of course nothing was wrong. Feeling fairly safe, I reset the circuit breakers and had the crew reset the generators. They both came on and the busses also came back. Plus all the power readings looked perfectly normal from the voltage to the power drawn across all 3 phases for all 4 generators. So, I went back to sleep. About an hour later the crew woke me up again and told me "we lost three now" I asked "we lost number 3 too now!?" The dude said "No, we lost number 2, 3, and 4" I got up without further conversations and went straight to the contacts ripped of the panels and again nothing. Check the fault codes and the same two had the generic fault codes usually fixed by power cycles. The fault code for the number 3 on the other had was a 50/50 between shorted generator windings or bad control unit. Luckily the control units sit in fairly accessible areas inside the plane and I had a spare one with me as part of my "just in case we need this kit" After seeing the codes, I went up to the crew had them turn off the three generators. I pulled all the circuit breakers for all 3. I went up to the analog contactors and gave them a few good wacks. I pulled off the connectors for the control units for bot gen 2 and 4 then outright swapped the connection between because well, magic. A trick that happens to work to get a plane off the ground that keeps getting these particularly fault codes. The plane almost always flies fine then when it lands we swap them back and the problem doesn't come back. As for the number 3 generator's control unit I slaved in the new unit. With things all moved around I had the crew turn all 3 generators back on and they where all golden. With power all good to go, I finished replacing the number 3 control unit very carefully, even if it was just the mounting hardware. The aircraft flew perfectly fine for the rest of the flight and all the remaining flights back home. Once home i restore the control units for number 2 and 4 back to how they should be. I annotated the maintenance forms they had been swapped back and of course the plane flew fine for the next 2 months or so before I stopped keeping track. At leas as far as the main power distribution systems.
Too many RUclips "explaners" would have simply mentioned the RAT as a source of electricity and gone on from there. Thanks for the mini-physics lesson.
Been watching your stuff for years and have loved your approach to engineering(and life) education. As an aviation engineering nerd as well, I love this crossover arc. One topic I would love to see covered is geared turbofan engines. Lots of interesting engineering tradeoffs there I haven't seen covered anywhere yet.
Well done. Here's a scenario I faced many years ago that could be used to teach how the much simpler systems on small piston engine-powered aircraft work; namely, how the magnetos will keep the engine running even if the alternator fails. It isn't enough of a story to make a video about, but it could be a useful nugget nonetheless. I was piloting a Cessna 172 many years ago in instrument conditions at night on an IFR flight plan between Corvalis, Oregon and Seattle. At one point in the flight, I caught a very brief scent of an electrical fire, but very brief. Then I noticed the ammeter was indicating zero charging. Fortunately, I had plenty of battery-powered emergency light sources and a battery-powered GPS mounted to the yoke. I shut down as many electrical systems as possible to conserve aircraft battery power, talked to ATC, checked weather at alternate airports (all were below minimums), then ultimately elected to continue to Seattle where the weather was better. The engine hummed along just fine. I checked in with ATC about every 10 minutes (radio and transponder). By the time I got to within about 15 miles of Seattle the weather had cleared and I completed the flight VFR, and had plenty of power left in the batteries to turn on necessary lights and radios for the final phases. At the time I was a nugget instrument rated private pilot, so you can imagine my stress level, especially as I had my kid with me. Thanks again for this video.
Great video. I will definitely watch others and have been following for some time. My grandfather was an airline mechanic back in the 40s-60s. My father worked the reservation systems. I broke the chain and became an engineer rather than work for the same airline. Keep up the good work.
Great Video Jeremy! What I've always wondered is if the RAT would be better to be a ducted turbine, kind of like a Jet boat or jet ski turbine configuration. Its seems to me that it would be a more aerodynamic config.
When I first saw the re-enactment on Air Disasters, it took me 5 seconds at the beginning of the documentary to recognize exactly what the problem was as soon as the first officer reported low oil temp and high oil pressure, long before any mention of fuel. All I had to do was think; What could cause a the oil in a jet engine to suddenly be too cold? -- A massive fuel leak at the engine with ice cold fuel!. Regardless of a checklist, it just comes from common sense and knowing engines well for many years, and understanding what engine gauges are telling you. Even having never flown jets myself.
Wow thank you for this story. I completely missed this incident at the time, not sure if it was just a lack of media coverage but I appreciate your time and effort to bring this to us.
August 2001 was when American media became fixated on shark attacks. There is even a Wikipedia page on it "Summer of the Shark". They basically ignored any story happening to airplanes -- at least until about a week and a half into September 2001
Wow wow wow! This was absolutely incredible. Not only was your story telling ability superb, I learned about a number of airplane specific mechanisms I had no idea about
Excellent explanation of the scenario of a improbable cascading chain of events that can result in aviation mishaps. You mentioned loss of cabin pressurization. That is also a function of the engines via bleed air system. Thanks for sharing.
IDEA FOR NEW VID: I would like to see you tackle attitude indicators (gyros) not precessing over long-haul flights. Thank you for all your hard work and making complex topics easy to understand.
For those worried about fly by wire. Most if not all cars today are fly by wire. Fords last vehicle to convert over was around 2006. So these systems cars and planes are pretty safe, not saying something could go wrong, but then there are many other things that can fail. Fly by wire you more than likely drive one.
i dont think any cars are fly by wire. drive by wire maybe. jokes aside, brakes and steering wheel are still mechanically linked in almost all cars. only the gas pedal has been electronic for ages now.
Several newer cars especially all electric have gone to no mechanical links now and more will be doing so as they are redesigned. Like most things the high end cars get it first and they move it down through to the others as the improve and streamline production and costs go down. One thing that was slowing down the change over was getting government regulations. It took years just to get LED lighting approved.
I love that you're into planes! I've been a huge fan of yours since you were picking through the curbside trash and making tools out of old vacuum cleaner motors. Now that you cover another of my favorite subjects, your channel has achieved a new level of awesomeness. You should cover some 400 hz motors that come in aircraft and advantages and disadvantages to high frequency electrical systems. It's really cool that a motor at 400 hz can produce 30 hp and not be much bigger than an electric drill.
From you set the scene of being over the ocean with both engines out and the plane being FBW I had a hunch that you would be talking about the RAT. Also, this video means so much to me because it highlights just how important the communication of big ideas are, even if the concept is simple. Energy conservation still holds no matter what!! I dream of being a half-decent science/engineering communicator like you. Keep up the great work Mr. Fielding!
Thank you Jeremy for a wonderful explanation of RAT's and the events that occurred during the flight. Personally I could have done without the plastic cups but still an excellent presentation.
Outstanding narration-- shows thoughtful attention to full context and detail. We subscribed. * As we listened, your clear explanation began to lose focus. Fortunately, you recovered control and dramatic momentum. This is not to fault your detail, so much as to remind you that your viewers are still seated in a doomed airliner, holding their collective breath.
Any landing U can walk away from is a good landing. Truly fascinating story about a) backup systems as safety factor i.e. redundancy in engineering, & b) pilot error i.e. just do & ignore the checklist which is is own backup system. In today's world I'd expect real time software analysis & output warnings suggesting possible fuel leak(s) or other conditions based on monitored inputs pilots see individually.
@@Jack-he8jv Engineering issues notwithstanding, both 737 Max crashes had major pilot/maintenance errors as contributing factors. There are always multiple contributing factors and it's a bad idea to ignore all but one.
It was a certification and training problem. A new type rating should have been required, but wasn't. Retraining should have been required, but it wasn't. The mcas was a bad idea, having it fed info from a single sensor doubly so. All because Boeing did not want the plane to require a new type rating, because airlines don't like that. Having the authorities outsource the certification process to the manufacturer wasn't a brilliant move either.
Wonderful Jeremy! Not only is your new series a great augmentation to videos focusing on air emergencies, but it also brings in the very important part to describe the engineering aspects built into the systems to mitigate problems. Your style of the presentation, including little demonstrations such as the oil viscosity impact really brings people closer to the engineering. I really think this might indeed get more people interested, if not actively involved into technology. I have followed your channel for years and it is amazing to observe how your projects, communication style and outreach to the next generation of engineers just is on a constant steep incline. Keep up this great and important work!
What a great story. As it turned out, I was actually stationed at Lajes Field in the Azores when that happened. It was amazing to see how far the plane bounced and then to see the wheels and tires worn down to the axles because as stated the brakes locked up. Needless to say the runway was covered with pieces of metal from the rough landing.
Great video, Jeremy. WRT other topics, in one of our flight mechanics and controls classes in grad school the Prof. talked about a microburst incident at DFW. That was a long time ago, and I think the topic was angle of attach and flow separation.
Wow !!! What a fantastic video. You describe a complex system and simplify it. So even a non-pilot like myself can understand it. I have to say that as I was watching it I almost felt like I was one of the passengers and it gave me goosebumps. I really think the analogy of using those various plastic cups filled with water visually aided your description of the amount of fuel that was being used and a description of friction etc, thanks again. Fantastic job!
As an airline pilot, I applaud your very accurate description of what happened on this aircraft. Proper analysis, proper terminology, and simple enough for a non-engineer to understand. The big bonus here is the opportunity to teach physics, chemistry and engineering with the story as a background. Well done!
100%. That ability to communicate clearly so that anyone could understand is so important!
COMPARE SU1492 TO JL516 IN YOUR NEXT VIDEO 👀
As a passenger I want to know if short distance airplane cabin crews trained for any of these situations or are they only trained to sell sandwiches?
Amazing and passionate storytelling. Great dad! Inspirational engineer. So many badges of honor that you wear. Thank you!
I have spent 20 years designing software for electrical power systems for anircraft and I loved your accurate discussion on this little known system.
Largely correct but one point of note, even if you don't have "fly by wire" flight controls you still need a RAT. The 767, CRJ, and E145 I've flown all have RAT's and are not fly by wire. Reason being at a speed of .84 mach there's not enough mechanical force from both pilots put together to be able to move any of the primary flight controls. Simply too much air resistance. RAT's can either be an additional electrical generator or a hydraulic pump directly powering the PCU (power control unit) that the cables hook to that move the flight controls. Hope this cleared something up, overall excellent video!
I love how you so much love the technology you talk about, I can see in your face how much passion you have, I've been an electrical fitter for almost 50 years, I build control panels from scratch and after all these years I still love my job, great videos
Thanks!
as an engineer myself I fully understand the conservation of energy you demonstrated. sometimes when you instinctively understand things you tend to gloss over important details parts when explaining them to others. I commend you Jeremy, for putting together a vary concise, complete and understandable demonstration.
well done!
Off on a Tangent: A person I worked with for years was on that flight. There was of course a class action suit launched by the passengers after this. They reached a settlement nearing $ 50 million Cdn. Out of that, the legal team received nearly half. While that sounds outrageous, these kinds of suits demand huge time in research, and payment of expert witnesses. The rest of the money was divided in terms of more money going to passengers who were injured using the emergency slides. A broken ankle on an elderly person, for example, can lead to substantial loss of quality of life. My co-worker friend suffered no injuries, and was stoic enough not to mention the nightmares and such. At the end of everything, he realized $ 8000.00 Cdn. Basically made whole on his expenses, and not much else. So when you hear of these big settlements, don't assume that the plaintiffs are making out like bandits.
The law team did.
@@fromthepeanutgallery1084 yep, it seems like no matter what the story is, the lawyers always seem to be the ones who get the lions share, I don't care how much effort they went to, it can't be more deserving than some innocent person who goes through hell and may also be damaged for life...
@@fromthepeanutgallery1084 Well, I don't know. It's easy to cast aspersions on lawyers in general. It does seem like a rather generous pay day, but we don't know the expense side of the ledger. I'm not sure what civil and criminal lawyers are currently charging per hour in court, but last I saw it seemed rather exorbitant, and I doubt the hourly rate has gone down since.
In Canada police and the Crown Attorney's are pretty corrupt when it comes to looking the other way when the wealthy/connected or corporate abuse the public, so I'm inclined to cut Civil Litigators a bit of slack seeing that they are about the only path to justice in these kinds of matters.
@@rodchallis8031If the only path to justice costs $600/hr, it effectively means there is no justice for normal people. Not sure if it's ever been different though.
@jonahwhale9047 Why would the crew/engineers get a reward? Firstly they're not the plaintiffs, second they are just doing their job and on top of that the pilots neglected to check the checklist when they noticed lower than expected fuel which potentially made the incident much worse than it needed to be.
I just watched this video. It's the first one I've ever seen of yours. Excellent job. I'll be tuning in in the future.
Amazing story and amazing job explaining it to a noob like me. As someone who occasionally flies for work, when you described the cabin lights going out and the second engine shutting down (and the ensuing silence) I literally felt sick. I could imagine how tense and worried I’d be. Great video.
This is one of my favourite air "disasters". Your explanation of conservation of energy reminded me of a few months I bought my 2000 Honda Insight. Was filling up and a guy at the fuel station told me I should put a windmill on the front of the car attached to a generator to charge the batteries. That way, it would recharge as I drove and I'd never have to buy fuel again! I tried to explain that "in this house we obey the laws of thermodynamics" but his suggestion was to just use a large windmill! Finally after going around in circles a few times I told him that he was a genius with a world changing idea so he should invent himself and make billions. I always wonder if that guy went home and started playing with oscillating fans in his garage.
Sadly for him, Kia were ahead of the game... the Kia Niro EV (and others) has a "Vehicle-to-Load" system. There is (dependent on country) a 230 volt, 16 amp power point inside the cabin. All you need to do is plug the charge-cable into the charge-point on the front of the car, feed the cable in through the window, and plug it into the Vehicle-to-Load socket... Now you can drive forever!
(I don't know why Kia did not build the cable into the car, it is quite ugly, and you get cold in winter! Ahh well, small price to pay, I s'pose, maybe in next year's model.)
WhaDaYa mean Jeremy... you're just confusing me with all this "Conservation of Energy" nonsense! 😠
Yeah... of course I know about thurma-dye-nam-ickxs! 😜
Your best video. Great story telling + clear explanation. Great work! Thank you.
I clicked on this link and was happily surprised to see your face. I haven't seen your videos in a couple of years, despite the fact that I'm subscribed to your channel. Nice to see you again. Well done on the video.
Props to the pilots and flight attendants! Amazingly skilled pilots! You saved lives
Yes. People think of the cabin crew as flying waiters but they are not there to serve you, they are there to save you.
An EXCELLENT video, Jeremy! I spent a lot of years doing or supporting aircraft maintenance, both in the military and for a major airline, so I was already familiar with what a ram-air-turbine (RAT) is and it's importance. What I particularly like is your engineering and physics based approach to the discussion. I hope you are inspiring lots of young people to pursue the STEM topics.
Another interesting topic may be the "Gimli Glider" incident in Canada, several decades ago. A large passenger aircraft on a trans- continental flight ran out of fuel about halfway across. The complicating factor here is that Canada was in the middle of transitioning from the British Imperial measurement system to the Metric system, revenant documents were not updated, and more. One of the pilots knew the area, because he had served at a (closed) RCAF base nearby. That knowledge, and the RAT, resulted in a successful landing. I believe the aircraft was repaired and put back into service.
At this point I would normally rant about the idiocy of the USA not making metric mandatory instead of just the current status of "legal". (The other two countries are each smaller than most US States.) But maybe that can be another video.
I naturally assume that your video is now an integral part of pilot and engineer training.
The pilots will learn not to miss in their panic, that comment above the list, and stop the fuel from reaching the rupture.
The universe was not built upon Metric, and it is an inferior, less precise McGuffin of a hubristic scientism rampant among the over-educated, and congruently less clever.
Jeremy following you in Rwanda, well done your lectures are helpful to us, in developing our minds on those complicated issue due to unperfect explanation we did got in past
As usual you managed again to explain an issue in a simple way but to the core. Like my late father who was a pilot, instructor and examiner for technicians told me, "Its not hard to explain things in a complex way, but to explain things in a simple way you must really understand and know what you are talking about."
This is such an interesting story! We need more engineering stories like this!
There are more for sure!
Let’s hear them! I’m all in!
The cup illustration put the pieces together for me.
Man, excellent video! That's an incredible situation and you've done a fantastic job of explaining it to us!
Thanks!
You're a good storyteller. Looking forward to seeing more; very entertaining and educational. Thank you!
Mr Fielding, thank you for your attention to detail as usual.
This guy is so very good in description and delivery. Great story teller!
As usual, a great video. You present the content in a straightforward way without clickbait-y titles.
It's the good kind of clickbait, intriguing and interesting but still perfectly truthful!
Love your work Jeremy. You are a great communicator.
A fantastic story with tons of education mixed in! I hope you make more like this one.
Curiosity and not being afraid to dive in, that's a really good way to learn.
You are an excellent presenter.
Thanks so much for your videos. You are a blessing to us all.
Mr Fielding always explains everything that all layman can understand. Just awesome as all his videos, always awesome.
This video is such an incredible lesson by using an emotionally engaging story to mentally step through the engineering process of designing a well balanced and practical machine with just enough emergency gear! ❤
Your explanation of ram air turbine physics made me interested in the energy absorption. After a quick Google, I found out that windmills do indeed attenuate wind speed. Apparently you can lose up to 80% of the output by spacing them closely in a wind farm. Interesting.
I've been shot at and I've done other things, but to this day the proudest thing I've done was fixing 5 different engine generator problems while in the middle of the ocean between the UK and Iceland.
As an electrician flying on a C-130 on our way back home after picking up the aircraft from Bagram AFB, I was of course woken up mid flight to see what I could do.
The first time I was woken up we had lost 2 of the 4 main generators and the corresponding electrical busses didn't automatically swap over to the remaining generators to prevent power disruption. This alone is extremely unusual, there are 4 main electrical distribution busses that are connected to main engine generators by 8 contactor rated for 210vAC @ 400hz and 300 Amps. The contactors are arrange in a way where they are automatically energized and de-energized by the generators themselves to switch power between the main bus so no one generator accidentally tries to turn a different generator into a motor.
Once all 4 engines and generators are up you can technically loose 4 of the 8 contactors with out getting a single warning and with out loosing a single distribution bus, under highly specific and perfect conditions.
Prior to this event the only time i had ever seen two generators go out at once, where the busses also didn't automatically kick over. It was on a C-130 we had just taken out of the bone yard and where preparing it to be flyable again. After the 3 function test flight the aircraft's crew called down with an in flight emergency. When I examined the system some 4awg wires had chaffed each other's multi layered insulations that include fiberglass wrappings and some polymers that give you cancer if you simply pronounce the name of the molecule chain. Needless to say there where lots of scorch marks.
As I remembered that incident I checked the fault codes but they where generic and usually fixed by a power cycle while on the ground but obviously we were not on the ground. I also, sniffed around for some magic smoke but nothing. As we where somewhere between the UK and Iceland and still had some power, I had the crew turn off the two faulted generators. I pulled all the circuit breakers for the two generators and then started to remove the paneling for the contactors to make sure nothing was going. Of course nothing was wrong.
Feeling fairly safe, I reset the circuit breakers and had the crew reset the generators. They both came on and the busses also came back. Plus all the power readings looked perfectly normal from the voltage to the power drawn across all 3 phases for all 4 generators. So, I went back to sleep.
About an hour later the crew woke me up again and told me "we lost three now" I asked "we lost number 3 too now!?" The dude said "No, we lost number 2, 3, and 4"
I got up without further conversations and went straight to the contacts ripped of the panels and again nothing. Check the fault codes and the same two had the generic fault codes usually fixed by power cycles. The fault code for the number 3 on the other had was a 50/50 between shorted generator windings or bad control unit. Luckily the control units sit in fairly accessible areas inside the plane and I had a spare one with me as part of my "just in case we need this kit"
After seeing the codes, I went up to the crew had them turn off the three generators. I pulled all the circuit breakers for all 3. I went up to the analog contactors and gave them a few good wacks. I pulled off the connectors for the control units for bot gen 2 and 4 then outright swapped the connection between because well, magic. A trick that happens to work to get a plane off the ground that keeps getting these particularly fault codes. The plane almost always flies fine then when it lands we swap them back and the problem doesn't come back.
As for the number 3 generator's control unit I slaved in the new unit.
With things all moved around I had the crew turn all 3 generators back on and they where all golden.
With power all good to go, I finished replacing the number 3 control unit very carefully, even if it was just the mounting hardware.
The aircraft flew perfectly fine for the rest of the flight and all the remaining flights back home. Once home i restore the control units for number 2 and 4 back to how they should be. I annotated the maintenance forms they had been swapped back and of course the plane flew fine for the next 2 months or so before I stopped keeping track. At leas as far as the main power distribution systems.
@20:16 I wouldn't say that cabin pressurization is sacrificed, because it already stopped working when the engines stopped spinning.
Too many RUclips "explaners" would have simply mentioned the RAT as a source of electricity and gone on from there. Thanks for the mini-physics lesson.
Been watching your stuff for years and have loved your approach to engineering(and life) education. As an aviation engineering nerd as well, I love this crossover arc.
One topic I would love to see covered is geared turbofan engines. Lots of interesting engineering tradeoffs there I haven't seen covered anywhere yet.
Well done. Here's a scenario I faced many years ago that could be used to teach how the much simpler systems on small piston engine-powered aircraft work; namely, how the magnetos will keep the engine running even if the alternator fails. It isn't enough of a story to make a video about, but it could be a useful nugget nonetheless. I was piloting a Cessna 172 many years ago in instrument conditions at night on an IFR flight plan between Corvalis, Oregon and Seattle. At one point in the flight, I caught a very brief scent of an electrical fire, but very brief. Then I noticed the ammeter was indicating zero charging. Fortunately, I had plenty of battery-powered emergency light sources and a battery-powered GPS mounted to the yoke. I shut down as many electrical systems as possible to conserve aircraft battery power, talked to ATC, checked weather at alternate airports (all were below minimums), then ultimately elected to continue to Seattle where the weather was better. The engine hummed along just fine. I checked in with ATC about every 10 minutes (radio and transponder). By the time I got to within about 15 miles of Seattle the weather had cleared and I completed the flight VFR, and had plenty of power left in the batteries to turn on necessary lights and radios for the final phases. At the time I was a nugget instrument rated private pilot, so you can imagine my stress level, especially as I had my kid with me. Thanks again for this video.
Great video. I will definitely watch others and have been following for some time. My grandfather was an airline mechanic back in the 40s-60s. My father worked the reservation systems. I broke the chain and became an engineer rather than work for the same airline.
Keep up the good work.
Great Video Jeremy!
What I've always wondered is if the RAT would be better to be a ducted turbine, kind of like a Jet boat or jet ski turbine configuration. Its seems to me that it would be a more aerodynamic config.
You are a very skilled story teller!
A very informative video, your delivery style is so calm, relaxed and informative, keep at it!
When I first saw the re-enactment on Air Disasters, it took me 5 seconds at the beginning of the documentary to recognize exactly what the problem was as soon as the first officer reported low oil temp and high oil pressure, long before any mention of fuel. All I had to do was think; What could cause a the oil in a jet engine to suddenly be too cold? -- A massive fuel leak at the engine with ice cold fuel!. Regardless of a checklist, it just comes from common sense and knowing engines well for many years, and understanding what engine gauges are telling you. Even having never flown jets myself.
I really enjoy your videos, your delivery style etc. Your parasitic energy loss explanation was really well put.
Thanks.
Mentor Pilot collaboration!! You are amazing and so is he, great team 👏
Wow....interesting teaching,.thank you very much for your time and insight
Good one. This is the first time I've seen something from you in a while, glad you're ok. No idea you were interested in Aircraft,.
Wow thank you for this story. I completely missed this incident at the time, not sure if it was just a lack of media coverage but I appreciate your time and effort to bring this to us.
lack of media coverage probably because no one died
August 2001 was when American media became fixated on shark attacks. There is even a Wikipedia page on it "Summer of the Shark". They basically ignored any story happening to airplanes -- at least until about a week and a half into September 2001
Wow wow wow! This was absolutely incredible. Not only was your story telling ability superb, I learned about a number of airplane specific mechanisms I had no idea about
I knew on Smarter Every Day you were worth following. You more than deliver. Well done.
Excellent explanation of the scenario of a improbable cascading chain of events that can result in aviation mishaps.
You mentioned loss of cabin pressurization. That is also a function of the engines via bleed air system.
Thanks for sharing.
Jeremy this a great video . I was stressing as you told it. Love your videos buddy
Clear, concise presentation by a very easy to listen to person.
VERY well done Jeremy. Well research, well presented by you, and well produced. Thank you
IDEA FOR NEW VID: I would like to see you tackle attitude indicators (gyros) not precessing over long-haul flights. Thank you for all your hard work and making complex topics easy to understand.
This was a absolutely fantastic video. I am blown away.
Thank you for the great content. One of my favorite channels. I wish we had teachers like you in our grade schools. You are very talented.
Excellent 👌
I loved this video. Well done
For those worried about fly by wire. Most if not all cars today are fly by wire. Fords last vehicle to convert over was around 2006. So these systems cars and planes are pretty safe, not saying something could go wrong, but then there are many other things that can fail. Fly by wire you more than likely drive one.
i dont think any cars are fly by wire. drive by wire maybe. jokes aside, brakes and steering wheel are still mechanically linked in almost all cars. only the gas pedal has been electronic for ages now.
Several newer cars especially all electric have gone to no mechanical links now and more will be doing so as they are redesigned. Like most things the high end cars get it first and they move it down through to the others as the improve and streamline production and costs go down. One thing that was slowing down the change over was getting government regulations. It took years just to get LED lighting approved.
Excellent video! Enjoyed this very much!
I love that you're into planes! I've been a huge fan of yours since you were picking through the curbside trash and making tools out of old vacuum cleaner motors. Now that you cover another of my favorite subjects, your channel has achieved a new level of awesomeness. You should cover some 400 hz motors that come in aircraft and advantages and disadvantages to high frequency electrical systems. It's really cool that a motor at 400 hz can produce 30 hp and not be much bigger than an electric drill.
Wow, THIS is the type of information I love you for sharing!
You are an amazing, generous and kind man.Awesome story, very well presented, best to you Jeremy from James
I really enjoyed this! Learned a lot!
Jeremy you’re the man. Another fantastic vid. Many thanks. ❤️
From you set the scene of being over the ocean with both engines out and the plane being FBW I had a hunch that you would be talking about the RAT. Also, this video means so much to me because it highlights just how important the communication of big ideas are, even if the concept is simple. Energy conservation still holds no matter what!! I dream of being a half-decent science/engineering communicator like you. Keep up the great work Mr. Fielding!
Great video keep up the good work
Thank you Jeremy for a wonderful explanation of RAT's and the events that occurred during the flight. Personally I could have done without the plastic cups but still an excellent presentation.
Fantastic explanation of this account! Thanks for sharing!
Very interesting case study, I was glad this had a happy ending.
Thanks for the Explanation. You made it very interesting!
Well done. You are a gifted educator
Fascinating! Thank you!
THANK YOU S O MUCH FOR DOING THIS VIDEO I LOVE THESE TYPES OF VIDEOS AND I LOVE YOUR VOICE!!!!!!!!!!!!!!!
Absolutely superbly done,😁👍
You have a great channel, Jeremy,. Thank you for making these videos. 👍
Beautifully described, thanks.
excellent job describing in detail what happened. You did lots of research
I enjoyed your predestination. it was refreshing because it wasn't as refined as some other deliveries of aero topicks
The pilot became a local hero in Quebec. His life's story is very captivating.
Outstanding narration-- shows thoughtful attention to full context and detail. We subscribed.
* As we listened, your clear explanation began to lose focus. Fortunately, you recovered control and dramatic momentum. This is not to fault your detail, so much as to remind you that your viewers are still seated in a doomed airliner, holding their collective breath.
The wind turbine, classic second law of thermodynamics. I wish you would have stated that but this was a great video!
Any landing U can walk away from is a good landing. Truly fascinating story about a) backup systems as safety factor i.e. redundancy in engineering, & b) pilot error i.e. just do & ignore the checklist which is is own backup system.
In today's world I'd expect real time software analysis & output warnings suggesting possible fuel leak(s) or other conditions based on monitored inputs pilots see individually.
737 max: redundancies? sounds like communism!
@@Jack-he8jv Engineering issues notwithstanding, both 737 Max crashes had major pilot/maintenance errors as contributing factors. There are always multiple contributing factors and it's a bad idea to ignore all but one.
It was a certification and training problem. A new type rating should have been required, but wasn't. Retraining should have been required, but it wasn't. The mcas was a bad idea, having it fed info from a single sensor doubly so. All because Boeing did not want the plane to require a new type rating, because airlines don't like that. Having the authorities outsource the certification process to the manufacturer wasn't a brilliant move either.
Wonderful Jeremy! Not only is your new series a great augmentation to videos focusing on air emergencies, but it also brings in the very important part to describe the engineering aspects built into the systems to mitigate problems. Your style of the presentation, including little demonstrations such as the oil viscosity impact really brings people closer to the engineering. I really think this might indeed get more people interested, if not actively involved into technology. I have followed your channel for years and it is amazing to observe how your projects, communication style and outreach to the next generation of engineers just is on a constant steep incline. Keep up this great and important work!
Great video! Thanks for sharing!
Great story, with just the right amount of technical information.
What a great story. As it turned out, I was actually stationed at Lajes Field in the Azores when that happened. It was amazing to see how far the plane bounced and then to see the wheels and tires worn down to the axles because as stated the brakes locked up. Needless to say the runway was covered with pieces of metal from the rough landing.
Great video, Jeremy. WRT other topics, in one of our flight mechanics and controls classes in grad school the Prof. talked about a microburst incident at DFW. That was a long time ago, and I think the topic was angle of attach and flow separation.
Wow !!! What a fantastic video. You describe a complex system and simplify it. So even a non-pilot like myself can understand it. I have to say that as I was watching it I almost felt like I was one of the passengers and it gave me goosebumps. I really think the analogy of using those various plastic cups filled with water visually aided your description of the amount of fuel that was being used and a description of friction etc, thanks again. Fantastic job!
Great compilation of facts and how it all ties in together!
That's really really impressive.
Great presentation
Jeremy! You are a great guy
Excellent story telling!
Thanks jeremy 😍
One of my favorite videos and thank you for explaining everything!
Great video! I've never heard of a RAT as a backup. I always love learning about airplanes.
Great video!
Dang Professor Jeremy, I'm digging the AV vid. Keep hem coming🙂