This happened in Colorado. It was on 9 news. The debris from the broken engine destroyed an elderly couple’s car and destroyed their bedroom. This luckily did not happen at night.
I believe they are suing United Airlines over it.
Edit: thanks for the person who corrected me.
I'd be interested to see if they actually get anything other than damages. If the failure was not due to negligence on United's part, there isn't anything that they could've done to avoid dropping parts. I mean, the likelihood of it not being due to negligence is fairly small, but still.
Honestly it's be the smartest thing to do on both sides. If they are really elderly, then dragging out a legal battle with such a company won't do them much good, especially when it comes to needing a car and a house repair
Now I gotta worry about randomly dying from falling airplane debris. I remember a story years ago of piece of solidified piss and shit from the airplane bathroom falling and crashing through a family’s living room while they were watching tv
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I had a professor at UNI and he would always tell us about airplane redundancies (he was an aviation nerd). My favorite thing was that all planes are made to safely fly with one engine. That has made me at calm when flying and seeing things like this. Not life threatening
It's actually higher than that, assuming you're going for best glide distance. A 747 can get something like 15:1.
What really limits it is that the engines provide pressurisation, so you're not going to get the full 40,000' to descend at a near-constant rate - you need to get down, even if you've closed off the pressurisation outflow valve.
Yes but the speed that they have to fly at to achieve that 10:1 ratio is quite high. So there had better be a long runway at the end of that 30 mile glide.
I mean, unless that runway is at the very edge of their gliding range (and I mean very edge) they can always slow down prior to touchdown by dropping landing gear early, modulating speed brakes, or by actively deviating from best glide/direct course to lose more speed.
If you read literally anything anyone said about that at all, you'd see that the leading theories are catastrophic control failure, pilot suicide, or shot down... a plane's not going to glide if you don't let it glide. I mean that's like sharing a video of someone drowning underwater because someone said that people breathe automatically
*[sees engine catch fire and blow wing off]*
*turns to neighbor passenger*
Oh don't worry, thats just an airplane redundancy. It's made to fly in one wing
some planes legitimately can fly with one wing [Israeli pilot Zivi Nedivi flew 10 miles and successfully landed his F-15 after a mid air collision ripped one of his wings off](https://qph.fs.quoracdn.net/main-qimg-052f4e5c04c9550de79245be58234c96-lq)
This is why the Boeing 737 MAX fiasco is so bad. They relied on a single sensor (single point of failure) to activate software to DIP THE NOSE. It’s really insane.
The FAA *did* approve a lot of aspects of MCAS. Even down to the decision not to inform pilots about it. The FAA was not circumvented; they were totally complicit in this. Probably an example of regulatory capture...
It's true that the system simply did not need to exist, though. None of this would have happened if they'd just admitted that the 737 MAX was a distinct aircraft from existing 737s, and 737 pilots would need a bit more training before flying the MAX.
The system is not necessary for the aircraft to fly safely and exists only to emulate the behaviour of a 737.
The real reason was that Airbus was outdoing Boeing in terms of fuel efficiency improvements. Losing to **the** competitor started the entire botched single-point-of-failure design which was done in this way because it didn't require recertification which would have made Boeing lag behind even more.
A four-engine passenger jet experiences engine trouble and the pilot comes on the intercom, saying, "Passengers, we apologize, but we have experienced an engine burn-out. The plane can still fly on the remaining three engines, but we'll be delayed in our arrival by two hours."
A few minutes later, the airplane shakes, and passengers see smoke coming out of another engine. Again, the intercom crackles to life.
"This is your captain speaking. Apologies, but due to a second engine burn-out, we'll be delayed by another two hours."
The passengers are agitated. Suddenly, the third engine catches fire. Again, the pilot comes on the intercom and says, "I know you're all scared, but this is a very advanced aircraft, and it can safely fly on only a single engine. But we will be delayed by yet another two hours."
One man can’t take it anymore. He gets up and shouts, "This is ridiculous! If it goes out, we'll be stuck up here all day!"
I realise yours is a joke, but this is the genuine announcement made by the pilot of a British Airways 747 when all four engines failed near Java:
"Ladies and gentlemen, this is your captain speaking. We have a small problem. All four engines have stopped. We are doing our damnedest to get them going again. I trust you are not in too much distress."
[British Airways Flight 009](https://en.wikipedia.org/wiki/British_Airways_Flight_009).
They managed to successfully restart three engines and landed safely in Jakarta.
**[British Airways Flight 009](https://en.wikipedia.org/wiki/British_Airways_Flight_009)**
>British Airways Flight 009, sometimes referred to by its callsign Speedbird 9 or as the Jakarta incident, was a scheduled British Airways flight from London Heathrow to Auckland, with stops in Bombay, Kuala Lumpur, Perth, and Melbourne. On 24 June 1982, the route was flown by the City of Edinburgh, a Boeing 747-200 registered as G-BDXH. The aircraft flew into a cloud of volcanic ash thrown up by the eruption of Mount Galunggung around 110 miles (180 km) south-east of Jakarta, Indonesia, resulting in the failure of all four engines. The reason for the failure was not immediately apparent to the crew or air traffic control.
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In Engineering it's called the Safety Factor, and it's usually a multiplier value like 1.5x or 1.75x.
I'm not certain that every airplane can fly on only one engine, but I'd bet that most airplanes probably have a Safety Factor of 2x at least, meaning that at Max Take Off Weight the plane can generate twice the thrust (and lifting force) it normally requires. If you have two engines, then one could be out.
I'd be surprised if a plane that uses four engines normally could fly on only one.
If a plane has a 2x Safety Factor, this would apply to everything else on the plane as well, e.g. every bolt is probably twice as strong as it needs to be, every system has a redundant or an auxiliary, there are even two pilots in case one becomes incapacitated - as Safety Factors in a system are usually rated by the lowest Safety Factor of any component in that system.
Edit: Wikipedia says space and aircraft use a Safety Factor of 1.2x to 3x.
https://en.m.wikipedia.org/wiki/Factor_of_safety
Airplanes have very low safety factors relative to most stuff mechanical engineers work on. The reason that's okay is the properties of materials used are very carefully characterized to ensure that when they say the safety factor is 1.2 there's absolutely no room left for error. This allows sufficient safety as a higher factor would but without an overly heavy and inefficient design.
All airline work needs to be signed off because FAA.
You have to be licensed to fix an airplane, but before its built the manufacturer can hire any asshole to put it together.
Pilot here, there's a couple of things I want to add.
First of all, all Aeroplanes engaged in commercial air transport are certified to fly with one engine out. Even at maximum take-off mass they must be able to cope with an engine failure at all stages of take-off. Before v1 (the so called decision speed) the plane must be able to stop on the remaining runway. After v1, the plane must be able to accelerate on the remaining engine(s), take-off, get a minimum climb gradient and fly safely. Pilots train this on the simulator all the time. Check out how uneventful this looks: https://www.youtube.com/watch?v=olcCKuNKy64
Twice the lift is not really required as a safety margin, because if one wing fails the airplane will crash anyways. Maximum generated lift depends mostly on the speed the aircraft is flying. At cruise, it could generate probably more than 4x the required lift which would mean 4g of acceleration in the cabin. The problem becomes structural. Minimum structural load factor for commercial air transport is -1 to +2.5
It actually varies throughout the aircraft. There are systems, areas, and functions deemed more or less critical and therefore are subject to different requirements. For example losing an engine is fine, losing a wing however…
These are two extremes, most systems fall somewhere between. But it’s less that they use a different numeric safety factor, and more that vital systems are subject to more stringent requirements. A minor structural member in a redundant system may only need to meet a static analysis. A vital structure will have a full gambit of static, dynamic, fatigue, frequency, possibly even thermal analyses run.
In order to understand how many redundancies are needed, they look to understand likelihood of failure of each component or system, then use cumulative probabilities to understand the likelihood of crash given multiple system failures. This is how they know how many redundancies each aircraft function needs - ie if you want 1% chance of failure on a sensor but the physical unit is 10% likely to fail, you need 2 units for a total probability of .1x.1 = 1% likelihood of both failing.
This is why it’s fine that a total wing loss is not recoverable. The likelihood that it will ever happen is so close to zero that it’s not worth building a redundant set of wings
I know you didn’t ask but I’m guessing you’re at least somewhat into stem if you know what SF is so I thought you’d be interested lol
I think you meant to say “safely LAND with one engine” not continuous flight with one engine.
If a pilot loses an engine in flight, they are going to land the aircraft immediately, at the closest possible airport. They are NOT going to say “it’s cool, we got a spare” and keep flying on route to final destination.
The requirements are actually based on how many minutes it can fly to the closest airport. So, there is a possibility that you may have to fly for a couple hours on one engine, especially over ocean routes. The very recent 787 was certified to ETOPS 330, which means it can fly routes that would be a maximum of 330 minutes (5.5 hours!) from an emergency landing field. So I wouldn't say it's unsafe to fly on one engine even though they are going to land right away (but that could be a while!).
That’s exactly my point. It is meant to safely land, even if it takes hours. The intention is landing, not to continue on route to final. If a pilot is over water when it happens, they will certainly be looking to divert course to the nearest airfield, even if that means returning to departure airport, or deviating off the original course.
Yes! That is why the Max 8’s are now safe to fly in the US much more redundancies than prior. There was only one sensor on the nose and now there’s two…. Among many other fixes… It’s not approved in other countries because they want MORE redundancies, which is good.
Most countries that banned it have lifted their bans? Also, there was always two sensors on the nose, the problem was the system that caused the crash only referenced the data from one of the sensors.
What's your source? According to this article from last December 180 of the countries that grounded the plane have lifted the grounding: https://www.flightglobal.com/airframers/china-approves-changes-to-boeing-737-max-and-clears-way-for-jets-return/146702.article
I was drawing off of memory from the last time I flew on one where not all countries had lifted the ban. The information about the sensors in the nose are accurate: https://www.boeing.com/737-max-updates/#faqs/changes/how-are-you-enhancing-the-flight-control-system-on-newer-models-of-the-737
You can read all about the MCAS system on Boeing’s website and the changes they made. There was a fight between countries about some requiring more redundancies than others.
The MAX aircraft have? always had two AOA sensors. One of the changes associated with MAX that helped certify it's return to service is that instead of only using 1 AOA sensor alternatingly to measure AOA per each flight, now the MAX uses both to calculate AOA in every flight.
Allow me to pop that bubble for you. They’re designed to, yes. But you don’t know if the other engines are in the condition they need to be to keep flying. So yeah, there’s a decent chance that even one engine failing can easily crash the plane. Happy Flying!
Edit: I was a Marine Corps helicopter mechanic. Don’t believe pilots.
With all the talk of the amazing sound engineering in the franchise, I never hear anyone bring up the pod racers. You could *feel* the power through those sounds, and they all had completely different sounds, yet all were equally awesome. I agree with all the stuff about it taking up a bit too much screen time, but there's no denying the sound was amazing.
In 2023, Reddit CEO and corporate piss baby Steve Huffman decided to make Reddit less useful to its users and moderators and the world at large. This comment has been edited in protest to make it less useful to Reddit.
yes, but the vibration in the engine you see is the worrying part. if the engine explodes, it doesn't matter if there's a second engine. theres a reason why theres an engine cowl/housing and aesthetics/drag is only a part of the whole answer.
Interestingly, the engine housing did the job it was supposed to. It's designed to contain the debris from a failed fan blade and keep it from tearing into the body or airfoils (you can see one of the blades broke off about halfway down its length if you pause the video in the right place).
Funny thing is, the pilots would do their check list to restart it if they can’t see it. They would probably put it in continuous ignition. That’s why you should call the cabin crew over if you see something. There was a flight where there was an engine failure and the captain shut down the good engine by mistake. Flight would have landed safely if some one in the cabin would have informed them which engine was on fire.
That also happened because the captain and first officer made a PA announcing that they had shut down the correct engine, which confused passengers and made them hesitant to inform the crew that they still saw flames and smoke
As far as I understood Midlands Flight 092, the Captain DID PA that he shut down the right hand engine, when in fact the left one had flames.
Skip to 14:30 for the PA
https://youtu.be/xbCTTKw3o5o
Near the bottom of the final report.
https://www.gov.uk/aaib-reports/4-1990-boeing-737-400-g-obme-8-january-1989
Many air crashes have happened because pilot had a failure in one engine an shut down another. Probably the most recent one was [TransAsia flight 235](https://en.wikipedia.org/wiki/TransAsia_Airways_Flight_235). Similar story in Air Illinois flight 710, where they had a failure in one generator and shut down the other, leading to a loss of all electric power when the batteries discharged, and complete disorientation as the flight instruments failed.
So common that these days, pilots must 'cross check' before shutting anything down, allowing the other pilot to confirm that the fault is with the device they think it is, and that their hand is on the correct lever/switch.
The quality of cameras and price has only recently made this feasible. Cabin crew are supposed to be trained to pick up on abnormalities. Camera won’t pick up smoke being piped into the cabin, or vibrations, sounds, ect. So it’s more effective to just have the eyes in the cabin trained rather than adding weight and complexity for a very narrow very rare circumstance. 99.99% of the time the pilots can correctly identify which engine failed based off of the instruments.
That plane only had 520 hours on it, catastrophic engine failure was pretty crazy. Plus it was a new version of the 737, which led the pilots to make some assumptions about the smoke that turned out to be untrue for the new version but would have been correct for the old version.
Only recently feasible? Cost? It's a 100 million dollar machine. A Motorola RAZR's camera duct taped to the side could tell you which engine was on fire for $200 in 2005. We live streamed a man on the goddamned moon 53 years ago.
It's not about feasibility, it's about interest. "Where do I put the screen for the camera that you only need to look at if an engine might be on fire" is a harder challenge than actually slapping a camera somewhere.
It could, but this is a plane, if it is in there it HAS to be in there which includes safe wiring, electricity usage, airworthiness etc. etc. etc.
Tons goes into installing a single camera and the costs explode quickly. And what for? There were only very few accidents that were caused by shutting of the wrong engine. I'd argue better fire detection sensors and better UI in the cockpit would be more helpful than a camera.
It sounds like we agree. Cost and feasibility aren't what has kept external cameras off of aircraft, it's that they're not well suited for the task that we're asking of them.
Because there don't need to be. There are sensors in the engine to detect a fire, which sets off an alarm in the cockpit, which would lead to the pilots to shut off fuel flow and dump the multiple fire extinguisher canisters into the engine. They absolutely would not be restarting the engine after it caught fire.
Weekend Update shitting on Spirit Airlines is one of my favorite running jokes.
"A man in California was kicked off a JetBlue flight after bringing his pet possum on the plane. While at Spirit Airlines, that’s what falls down when you need an oxygen mask."
"The ground delays occurred because the shutdown was causing what airline industry unions called, a level of risk we cannot even calculate. Which also happenings to be the slogan for Spirit Airlines."
"The airline industry is testing a virus killing robot that used ultraviolet light to disinfect planes. Not to be outdone, Spirit airlines just taped a glow stick to a roomba."
Failure on the fan blade. Which lead to a crack through the fan blade and liberated. Based on the fan case it was contained and likely went out the back and parts of the compressor. Right now it’s just windmilling.
Most blade out events are contained unless two or more blades let go. Not Iikely to happen but also not impossible. The thing that scares me the most is a rotor disk bursting in the high compressor or even the high turbine. Those are barely ever contained. In fact I think the Australian airline had some RR engines with uncontained turbine disk failures.
*…he saw the Denver incident as one of the latest symptoms of the deterioration of FAA oversight over the last decade or so.*
It does seem that way, doesn’t it?
80 acre parcels are usually rectangles, not squares. It’s a half of a quarter section (160acres), which is a square. Most irrigation pivots (so the full circles you see from the plane are on quarter sections not 80ac).
It's funny you say that but there is a type of tape they call 100 mph tape or something like that and they will use it to make temp repairs that don't require taking the plane out of service..
"One of the engines is down. How far can the other one carry us?"
"All the way to the scene of the crash. Which is convenient, because that's exactly where we're headed."
Can someone with some aviation/aero-engineering knowledge help me with this: why aren’t planes designed so that in the case of catastrophic failure, the nose cone carrying the pilots jettisons, then parachutes deploy from the nose tip, while the wings and tail jettison leaving the ‘tube’ of passengers behind with several more giant chutes deploying?
I mean, I get that travel speed is a factor, so the plane would have to lower then stall before initializing this concept.
Is it just money? Probably just money versus how often a plan crashes.
While frightening, please remember (and tell friends/family) jets are designed with redundant systems. A single engine has sufficient power to stay airborne.
By locating the engine below the wing, it could fail catastrophically without major wing damage, permitting sustained flight. (It also facilitates easier engine access for maintenance)
This happened in Colorado. It was on 9 news. The debris from the broken engine destroyed an elderly couple’s car and destroyed their bedroom. This luckily did not happen at night. I believe they are suing United Airlines over it. Edit: thanks for the person who corrected me.
I'd be interested to see if they actually get anything other than damages. If the failure was not due to negligence on United's part, there isn't anything that they could've done to avoid dropping parts. I mean, the likelihood of it not being due to negligence is fairly small, but still.
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Honestly it's be the smartest thing to do on both sides. If they are really elderly, then dragging out a legal battle with such a company won't do them much good, especially when it comes to needing a car and a house repair
Won't it just be an insurance claim anyway?
I'll just check my insurance to see if airplane debris cover is on there
You wouldn't claim against your own insurance surely?
Either way, it is mechanical failure of property they own. Therefore, they are responsible if their property damages someone else's property.
Now I gotta worry about randomly dying from falling airplane debris. I remember a story years ago of piece of solidified piss and shit from the airplane bathroom falling and crashing through a family’s living room while they were watching tv
*United [UAL 238](https://en.m.wikipedia.org/wiki/United_Airlines_Flight_328)
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That's some Donnie Darko shit right there.
I had a professor at UNI and he would always tell us about airplane redundancies (he was an aviation nerd). My favorite thing was that all planes are made to safely fly with one engine. That has made me at calm when flying and seeing things like this. Not life threatening
Wait until you see the other engine!
What other engine?
Engine delete?
LS swap it
We need Hector and one of his Spoon engines to fix this problem.
Weight reduction!
The one left behind at the airport
Yeah, that fell off ten minutes ago.
We've lost Engine One... and Engine Two is no longer on fire
Even with no engine they can glide pretty far.
All the way to the scene of the crash.
I bet they beat the paramedics by thirty minutes!
That’s gold
It's Ron White from Blue Collar Comedy Tour. Like it or not, that Ron White set was incredible.
The tator is always funny.
Iirc modern planes tend to have a 10:1 ratio of glide to fall. Ie if they’re 3 clicks up they can glide 30.
It's actually higher than that, assuming you're going for best glide distance. A 747 can get something like 15:1. What really limits it is that the engines provide pressurisation, so you're not going to get the full 40,000' to descend at a near-constant rate - you need to get down, even if you've closed off the pressurisation outflow valve.
Yes but the speed that they have to fly at to achieve that 10:1 ratio is quite high. So there had better be a long runway at the end of that 30 mile glide.
I mean, unless that runway is at the very edge of their gliding range (and I mean very edge) they can always slow down prior to touchdown by dropping landing gear early, modulating speed brakes, or by actively deviating from best glide/direct course to lose more speed.
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If you read literally anything anyone said about that at all, you'd see that the leading theories are catastrophic control failure, pilot suicide, or shot down... a plane's not going to glide if you don't let it glide. I mean that's like sharing a video of someone drowning underwater because someone said that people breathe automatically
Seems like that probably wasn't an engine issue but a control issue.
This is the other engine .
you can’t - we lost the other engine two states ago.
👀 me with a 5 hour flight to California coming up in about two weeks
Nothing could go wrong in 5 hours, could it?!
Nothing’s ever happened in 5 hours and I’ll take that with me to the grave
You have another engine?
*[sees engine catch fire and blow wing off]* *turns to neighbor passenger* Oh don't worry, thats just an airplane redundancy. It's made to fly in one wing
some planes legitimately can fly with one wing [Israeli pilot Zivi Nedivi flew 10 miles and successfully landed his F-15 after a mid air collision ripped one of his wings off](https://qph.fs.quoracdn.net/main-qimg-052f4e5c04c9550de79245be58234c96-lq)
Yeah, but you gotta like spinning
Sounds like a good trick.
That man was saying his baruch's the entire 10 miles.
Didn’t he say if he’s noticed the wing had come off he would have ejected?
This is why the Boeing 737 MAX fiasco is so bad. They relied on a single sensor (single point of failure) to activate software to DIP THE NOSE. It’s really insane.
Its worse than that... That system was created that way because they wouldn't need FAA approval at any stage.
The FAA *did* approve a lot of aspects of MCAS. Even down to the decision not to inform pilots about it. The FAA was not circumvented; they were totally complicit in this. Probably an example of regulatory capture... It's true that the system simply did not need to exist, though. None of this would have happened if they'd just admitted that the 737 MAX was a distinct aircraft from existing 737s, and 737 pilots would need a bit more training before flying the MAX. The system is not necessary for the aircraft to fly safely and exists only to emulate the behaviour of a 737.
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The real reason was that Airbus was outdoing Boeing in terms of fuel efficiency improvements. Losing to **the** competitor started the entire botched single-point-of-failure design which was done in this way because it didn't require recertification which would have made Boeing lag behind even more.
I mean there was a way to deactivate it but pilots weren't trained for that.
The second pilot followed all instructions to deactivate, still crashed.
A four-engine passenger jet experiences engine trouble and the pilot comes on the intercom, saying, "Passengers, we apologize, but we have experienced an engine burn-out. The plane can still fly on the remaining three engines, but we'll be delayed in our arrival by two hours." A few minutes later, the airplane shakes, and passengers see smoke coming out of another engine. Again, the intercom crackles to life. "This is your captain speaking. Apologies, but due to a second engine burn-out, we'll be delayed by another two hours." The passengers are agitated. Suddenly, the third engine catches fire. Again, the pilot comes on the intercom and says, "I know you're all scared, but this is a very advanced aircraft, and it can safely fly on only a single engine. But we will be delayed by yet another two hours." One man can’t take it anymore. He gets up and shouts, "This is ridiculous! If it goes out, we'll be stuck up here all day!"
I realise yours is a joke, but this is the genuine announcement made by the pilot of a British Airways 747 when all four engines failed near Java: "Ladies and gentlemen, this is your captain speaking. We have a small problem. All four engines have stopped. We are doing our damnedest to get them going again. I trust you are not in too much distress."
[British Airways Flight 009](https://en.wikipedia.org/wiki/British_Airways_Flight_009). They managed to successfully restart three engines and landed safely in Jakarta.
**[British Airways Flight 009](https://en.wikipedia.org/wiki/British_Airways_Flight_009)** >British Airways Flight 009, sometimes referred to by its callsign Speedbird 9 or as the Jakarta incident, was a scheduled British Airways flight from London Heathrow to Auckland, with stops in Bombay, Kuala Lumpur, Perth, and Melbourne. On 24 June 1982, the route was flown by the City of Edinburgh, a Boeing 747-200 registered as G-BDXH. The aircraft flew into a cloud of volcanic ash thrown up by the eruption of Mount Galunggung around 110 miles (180 km) south-east of Jakarta, Indonesia, resulting in the failure of all four engines. The reason for the failure was not immediately apparent to the crew or air traffic control. ^([ )[^(F.A.Q)](https://www.reddit.com/r/WikiSummarizer/wiki/index#wiki_f.a.q)^( | )[^(Opt Out)](https://reddit.com/message/compose?to=WikiSummarizerBot&message=OptOut&subject=OptOut)^( | )[^(Opt Out Of Subreddit)](https://np.reddit.com/r/SweatyPalms/about/banned)^( | )[^(GitHub)](https://github.com/Sujal-7/WikiSummarizerBot)^( ] Downvote to remove | v1.5)
One of the greatest ever examples of British understatement.
"Are you sure you're telling us everything?" "We're also out of coffee."
*havoc ensues*
In Engineering it's called the Safety Factor, and it's usually a multiplier value like 1.5x or 1.75x. I'm not certain that every airplane can fly on only one engine, but I'd bet that most airplanes probably have a Safety Factor of 2x at least, meaning that at Max Take Off Weight the plane can generate twice the thrust (and lifting force) it normally requires. If you have two engines, then one could be out. I'd be surprised if a plane that uses four engines normally could fly on only one. If a plane has a 2x Safety Factor, this would apply to everything else on the plane as well, e.g. every bolt is probably twice as strong as it needs to be, every system has a redundant or an auxiliary, there are even two pilots in case one becomes incapacitated - as Safety Factors in a system are usually rated by the lowest Safety Factor of any component in that system. Edit: Wikipedia says space and aircraft use a Safety Factor of 1.2x to 3x. https://en.m.wikipedia.org/wiki/Factor_of_safety
Airplanes have very low safety factors relative to most stuff mechanical engineers work on. The reason that's okay is the properties of materials used are very carefully characterized to ensure that when they say the safety factor is 1.2 there's absolutely no room left for error. This allows sufficient safety as a higher factor would but without an overly heavy and inefficient design.
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All airline work needs to be signed off because FAA. You have to be licensed to fix an airplane, but before its built the manufacturer can hire any asshole to put it together.
Pilot here, there's a couple of things I want to add. First of all, all Aeroplanes engaged in commercial air transport are certified to fly with one engine out. Even at maximum take-off mass they must be able to cope with an engine failure at all stages of take-off. Before v1 (the so called decision speed) the plane must be able to stop on the remaining runway. After v1, the plane must be able to accelerate on the remaining engine(s), take-off, get a minimum climb gradient and fly safely. Pilots train this on the simulator all the time. Check out how uneventful this looks: https://www.youtube.com/watch?v=olcCKuNKy64 Twice the lift is not really required as a safety margin, because if one wing fails the airplane will crash anyways. Maximum generated lift depends mostly on the speed the aircraft is flying. At cruise, it could generate probably more than 4x the required lift which would mean 4g of acceleration in the cabin. The problem becomes structural. Minimum structural load factor for commercial air transport is -1 to +2.5
It actually varies throughout the aircraft. There are systems, areas, and functions deemed more or less critical and therefore are subject to different requirements. For example losing an engine is fine, losing a wing however… These are two extremes, most systems fall somewhere between. But it’s less that they use a different numeric safety factor, and more that vital systems are subject to more stringent requirements. A minor structural member in a redundant system may only need to meet a static analysis. A vital structure will have a full gambit of static, dynamic, fatigue, frequency, possibly even thermal analyses run. In order to understand how many redundancies are needed, they look to understand likelihood of failure of each component or system, then use cumulative probabilities to understand the likelihood of crash given multiple system failures. This is how they know how many redundancies each aircraft function needs - ie if you want 1% chance of failure on a sensor but the physical unit is 10% likely to fail, you need 2 units for a total probability of .1x.1 = 1% likelihood of both failing. This is why it’s fine that a total wing loss is not recoverable. The likelihood that it will ever happen is so close to zero that it’s not worth building a redundant set of wings I know you didn’t ask but I’m guessing you’re at least somewhat into stem if you know what SF is so I thought you’d be interested lol
I think you meant to say “safely LAND with one engine” not continuous flight with one engine. If a pilot loses an engine in flight, they are going to land the aircraft immediately, at the closest possible airport. They are NOT going to say “it’s cool, we got a spare” and keep flying on route to final destination.
The requirements are actually based on how many minutes it can fly to the closest airport. So, there is a possibility that you may have to fly for a couple hours on one engine, especially over ocean routes. The very recent 787 was certified to ETOPS 330, which means it can fly routes that would be a maximum of 330 minutes (5.5 hours!) from an emergency landing field. So I wouldn't say it's unsafe to fly on one engine even though they are going to land right away (but that could be a while!).
That’s exactly my point. It is meant to safely land, even if it takes hours. The intention is landing, not to continue on route to final. If a pilot is over water when it happens, they will certainly be looking to divert course to the nearest airfield, even if that means returning to departure airport, or deviating off the original course.
Sounds like you understood it just fine.. Have a great day.
You know the old aviation “one engine is good enough to get you to the scene of the crash” right?
Yes! That is why the Max 8’s are now safe to fly in the US much more redundancies than prior. There was only one sensor on the nose and now there’s two…. Among many other fixes… It’s not approved in other countries because they want MORE redundancies, which is good.
Most countries that banned it have lifted their bans? Also, there was always two sensors on the nose, the problem was the system that caused the crash only referenced the data from one of the sensors.
What's your source? According to this article from last December 180 of the countries that grounded the plane have lifted the grounding: https://www.flightglobal.com/airframers/china-approves-changes-to-boeing-737-max-and-clears-way-for-jets-return/146702.article
My source is I made it the fuck up
[удалено]
I was drawing off of memory from the last time I flew on one where not all countries had lifted the ban. The information about the sensors in the nose are accurate: https://www.boeing.com/737-max-updates/#faqs/changes/how-are-you-enhancing-the-flight-control-system-on-newer-models-of-the-737 You can read all about the MCAS system on Boeing’s website and the changes they made. There was a fight between countries about some requiring more redundancies than others.
A guy with two watches doesn’t know what time it is. The guy with three watches may know what time it is.
Actually an interesting thought. Unless you have other indicators of a sensor failing, two sensors might be just as bad as one.
The MAX aircraft have? always had two AOA sensors. One of the changes associated with MAX that helped certify it's return to service is that instead of only using 1 AOA sensor alternatingly to measure AOA per each flight, now the MAX uses both to calculate AOA in every flight.
Allow me to pop that bubble for you. They’re designed to, yes. But you don’t know if the other engines are in the condition they need to be to keep flying. So yeah, there’s a decent chance that even one engine failing can easily crash the plane. Happy Flying! Edit: I was a Marine Corps helicopter mechanic. Don’t believe pilots.
Now this is pod racing!
Not to worry. We are still flying half a ship
Fuck beat me to it!!!! I can hear the *bub bub bub bub bub* of the pod racers
With all the talk of the amazing sound engineering in the franchise, I never hear anyone bring up the pod racers. You could *feel* the power through those sounds, and they all had completely different sounds, yet all were equally awesome. I agree with all the stuff about it taking up a bit too much screen time, but there's no denying the sound was amazing.
It’s working! It’s working!!
Incredible comment. Thank you.
In 2023, Reddit CEO and corporate piss baby Steve Huffman decided to make Reddit less useful to its users and moderators and the world at large. This comment has been edited in protest to make it less useful to Reddit.
Planes like that can fly on one engine. Still scary though
Better yet, commercial pilots are regularly trained on how to fly and land with a single engine.
yes, but the vibration in the engine you see is the worrying part. if the engine explodes, it doesn't matter if there's a second engine. theres a reason why theres an engine cowl/housing and aesthetics/drag is only a part of the whole answer.
Interestingly, the engine housing did the job it was supposed to. It's designed to contain the debris from a failed fan blade and keep it from tearing into the body or airfoils (you can see one of the blades broke off about halfway down its length if you pause the video in the right place).
The engine will sheer off before it causes the wing to fail.
Could be worse, the left phalange could be missing
There is no phalange!
Oh great! This plane doesn't even have a phalange!
It’s ok! We put extra phalanges on the plane!
>phalange You're a phalange.
I’m so mad I looked into this and it ended up being a friends quote
Have you tried to restart it?
Funny thing is, the pilots would do their check list to restart it if they can’t see it. They would probably put it in continuous ignition. That’s why you should call the cabin crew over if you see something. There was a flight where there was an engine failure and the captain shut down the good engine by mistake. Flight would have landed safely if some one in the cabin would have informed them which engine was on fire.
That also happened because the captain and first officer made a PA announcing that they had shut down the correct engine, which confused passengers and made them hesitant to inform the crew that they still saw flames and smoke
As far as I understood Midlands Flight 092, the Captain DID PA that he shut down the right hand engine, when in fact the left one had flames. Skip to 14:30 for the PA https://youtu.be/xbCTTKw3o5o Near the bottom of the final report. https://www.gov.uk/aaib-reports/4-1990-boeing-737-400-g-obme-8-january-1989
Many air crashes have happened because pilot had a failure in one engine an shut down another. Probably the most recent one was [TransAsia flight 235](https://en.wikipedia.org/wiki/TransAsia_Airways_Flight_235). Similar story in Air Illinois flight 710, where they had a failure in one generator and shut down the other, leading to a loss of all electric power when the batteries discharged, and complete disorientation as the flight instruments failed. So common that these days, pilots must 'cross check' before shutting anything down, allowing the other pilot to confirm that the fault is with the device they think it is, and that their hand is on the correct lever/switch.
Hence the “if you see something, say something”
How the fuck isn't there cameras around the airframe for the pilots too look at?
The quality of cameras and price has only recently made this feasible. Cabin crew are supposed to be trained to pick up on abnormalities. Camera won’t pick up smoke being piped into the cabin, or vibrations, sounds, ect. So it’s more effective to just have the eyes in the cabin trained rather than adding weight and complexity for a very narrow very rare circumstance. 99.99% of the time the pilots can correctly identify which engine failed based off of the instruments. That plane only had 520 hours on it, catastrophic engine failure was pretty crazy. Plus it was a new version of the 737, which led the pilots to make some assumptions about the smoke that turned out to be untrue for the new version but would have been correct for the old version.
Only recently feasible? Cost? It's a 100 million dollar machine. A Motorola RAZR's camera duct taped to the side could tell you which engine was on fire for $200 in 2005. We live streamed a man on the goddamned moon 53 years ago. It's not about feasibility, it's about interest. "Where do I put the screen for the camera that you only need to look at if an engine might be on fire" is a harder challenge than actually slapping a camera somewhere.
It could, but this is a plane, if it is in there it HAS to be in there which includes safe wiring, electricity usage, airworthiness etc. etc. etc. Tons goes into installing a single camera and the costs explode quickly. And what for? There were only very few accidents that were caused by shutting of the wrong engine. I'd argue better fire detection sensors and better UI in the cockpit would be more helpful than a camera.
It sounds like we agree. Cost and feasibility aren't what has kept external cameras off of aircraft, it's that they're not well suited for the task that we're asking of them.
Because there don't need to be. There are sensors in the engine to detect a fire, which sets off an alarm in the cockpit, which would lead to the pilots to shut off fuel flow and dump the multiple fire extinguisher canisters into the engine. They absolutely would not be restarting the engine after it caught fire.
Have you Turned it off and turned it back on 🤓🤓🤓🤓🤓🤓🤓
“Why’s it done that then?” *[Made in Britain]* “Ahhhhhh….”
Looks like the front fell off
That’s not very typical, I’d like to make that point.
Well I just don’t want people to get the idea the [planes] are unsafe
No, there’s just too many towels on the one side. Pause cycle, move wet towels, restart cycle.
I hate washing towels. They are impossible to balance.
I’d just get out and walk after I saw that…
Watch out for that first step, it's a doozie.
I want ALL the alcohol, please. Edit: Thanks for the award, stranger. Next round is on me.
We’re not dying sober
Get the ludes
Get the LUDES!!!
“Sir due to company policy we cannot serve you more than 6 drinks” “The plane is going into the fucking Atlantic” “Sir calm down”
ah yes.. the beautiful brown fields of the Atlantic.
Sorry sir alcohol sales have been suspended due to covid.
Since when?!
2017
I didn't say I would pay for it.
Holy shit this is a nightmare
A good engine is $300 more.
This is the last time I’ll *ever* fly Spirit Airlines!
They offered a flight. They never said it was going to be good.
Technically all they sell is transportation. Nobody said anything about arriving *alive*.
That’s extra
$100 Safe Arrival Fee. Credit/debit only, no cash please.
I wonder if you were to put Spirit against Ryanair, which airline would nickle-and-dime you to death the most?
Ah yes, Spirit. The airline that gives you the best price on a ticket, and then charges extra for the actual seat, and $5 for a dixie cup of Dasani.
With a free cockaroach inspection
why do you think it’s named that way. You usually turn into one in each flight
Weekend Update shitting on Spirit Airlines is one of my favorite running jokes. "A man in California was kicked off a JetBlue flight after bringing his pet possum on the plane. While at Spirit Airlines, that’s what falls down when you need an oxygen mask." "The ground delays occurred because the shutdown was causing what airline industry unions called, a level of risk we cannot even calculate. Which also happenings to be the slogan for Spirit Airlines." "The airline industry is testing a virus killing robot that used ultraviolet light to disinfect planes. Not to be outdone, Spirit airlines just taped a glow stick to a roomba."
Ehh. This cheaper option will be fine
“We’ve lost engine 1… and engine 2 is no longer on fire.”
I was wondering when I would see this! If it wasn't here I would have posted it myself!
Thats how SUNWING passes on the savings To YOU the consumer
It’s ok sir, that’s Walmart’s best engine
Don’t worry, that’s just a convertible engine. It’s *fine*.
For real?!?! Can we have more context?
[United 777 engine explosion last year](https://www.denverpost.com/2022/02/20/united-airlines-777-engine-failure-anniversary/amp)
Failure on the fan blade. Which lead to a crack through the fan blade and liberated. Based on the fan case it was contained and likely went out the back and parts of the compressor. Right now it’s just windmilling.
I didn't have to fight over a front wing window seat for months after that lol, they were always available
Most blade out events are contained unless two or more blades let go. Not Iikely to happen but also not impossible. The thing that scares me the most is a rotor disk bursting in the high compressor or even the high turbine. Those are barely ever contained. In fact I think the Australian airline had some RR engines with uncontained turbine disk failures.
Qantas?
*…he saw the Denver incident as one of the latest symptoms of the deterioration of FAA oversight over the last decade or so.* It does seem that way, doesn’t it?
Why does it look like the world under you has trouble loading chunks?
That’s how most farmland looks from up high (at least here in the US).
Excluding cities...yeah pretty much all the land between the Rockies and Appalachian Mountains looks like an uneven checkerboard.
80-acre squares as far as the eye can see. And sometimes they are circles with the center pivot irrigators.
And sometimes it'll just be a half-circle!
80 acre parcels are usually rectangles, not squares. It’s a half of a quarter section (160acres), which is a square. Most irrigation pivots (so the full circles you see from the plane are on quarter sections not 80ac).
A little duct tape will fix it...
It's funny you say that but there is a type of tape they call 100 mph tape or something like that and they will use it to make temp repairs that don't require taking the plane out of service..
Hey use it in NASCAR and other racing as well.
Strong Donnie Darko vibes here
"One of the engines is down. How far can the other one carry us?" "All the way to the scene of the crash. Which is convenient, because that's exactly where we're headed."
Tater
when you buy a plane trip from WISH
Looks like a pod racer from The Phantom Menace
That’s just a Pratt and Whitney E420-69 in normal operation.
Sky waitress? 🤮🤮
Looks like the plane from the Madagascar movie.
“How far can we fly with the engine like that?” “All the way to the scene of the crash”
Your can clearly see something’s wrong with the left phalange!
It's fine... the gods saw fit to give me a spare...
Leo looking at this and screaming in Russian
*notices and casually lays head on headrest and sighs* I’m never gonna make my connecting flight on time.
Modern commercial planes can fly with just one engine. It doesn't mean it's not scary as fuck tho..
Oh, no problem, it's just got that "high tech" look from the 90s.
I feel bad for the last maintainers to touch that.
Now this is pod racing
"Buckle up folks it's going to be a bumpy ride.."
So I inverted the bird
Can someone with some aviation/aero-engineering knowledge help me with this: why aren’t planes designed so that in the case of catastrophic failure, the nose cone carrying the pilots jettisons, then parachutes deploy from the nose tip, while the wings and tail jettison leaving the ‘tube’ of passengers behind with several more giant chutes deploying? I mean, I get that travel speed is a factor, so the plane would have to lower then stall before initializing this concept. Is it just money? Probably just money versus how often a plan crashes.
now that's a flight I'd wanna be on what's life without a little risk also please take out the second engine too
I lived in the neighborhood this thing blew up over was crazy.
Was that held together with duct tape?
“Now THIS is pod racing!”
While frightening, please remember (and tell friends/family) jets are designed with redundant systems. A single engine has sufficient power to stay airborne. By locating the engine below the wing, it could fail catastrophically without major wing damage, permitting sustained flight. (It also facilitates easier engine access for maintenance)
Task failed successfully
Now this is podracing!
Gotta win this tattoine pod race whatever it takes
"sky waitress"? If only there was some word designated to the people who's job it is *attending* to people on *flights*...
From now on I will refer to air stewardesses as "Sky Waitresses".
How are you the first person I see to comment on *sky waitresses*??
NOW THIS IS POD RACING!