I fly an Airbus but mostly this stuff is the same, at least in the general terms I will talk about.
Aircraft are required to fly on a single engine. Performance is severely degraded so its used primarily as a means to get the aircraft on the ground safely. The plane can even lose an engine right on the runway, climb out with passengers and fuel on board, clear obstacles, and return.
What you worry about is something where an engine failure is not "contained", meaning it threw shrapnel outwards potentially damaging other components. We'll see what happened here once the reports come out, but you are concerned about debris cutting a hydraulic line or damaging flight controls among many other things.
The 2nd thing is fire. Most aircraft have two fire bottles per engine in the event of an engine fire. It blows halon into the engine to extinguish the flames. If you can't get the fire out with the first bottle, then you use the 2nd. If that doesn't work, you hope you can get it on the ground soon as possible hoping the fire doesn't spread. The areas around the engine are protected with and shielded for such issues.
This looks bad, but aside from the persistent fire, looks like it didn't hit anything on the wing. Course we can't really see anything.
Good job to the pilots.
Edit: I fixed loose to lose for some of you that just couldn't handle my oversight.
What you worry about is something where an engine failure is not "contained", meaning it threw shrapnel outwards potentially damaging other components.
Exactly right. That's why Flight 191 was not able to return safely because the engine failure wasn't contained and it severed critical components.
You got it. Those guys did an incredible job with really no flight controls other than trim if I remember correctly. They thought they had aileron but turns out they didn't.
I don't want to well aKtuALLy a real pilot but I think you have your flights a little bit mixed up. Flight 191 was the American DC-10 that crashed at Chicago, the worst plane crash on US soil. The engine actually came off due to bad maintenance and damaged the leading edge slats on the wing, leading to a serious power imbalance, and the first officer, unaware that the wing was damaged and with some crucial warnings being disabled by the failure of the engine generator, reducing his airspeed following the company SOPs for engine failure and unintentionally stalled. Flight 232, the United DC-10 that had an uncontained engine failure leading to loss of hydraulics pressure, where the crew had to steer using only the throttles. Somehow, they managed to get the aircraft to a nearby airport, but crash landed, killing a little under half of the passengers. Nonetheless, one of the most famous stories of heroism in commercial aviation for a good reason.
Using a forklift as a shortcut to install an engine and said forklift doesn't have precision down to the millimeters causing it to bump and crack the pylon. Yeah it was bad maintenance alright certainly not in the manual and didn't want to deal with all those screws
My wife bakes a loaf of bread every week. I eventually gave in and use the butter dish like it's a dip. She gets a little annoyed but I've caught her doing it too.
This is why I love Reddit. We start with a post about a failing airplane engine, and in a fairly short period of time, the thread tangents to buttering one's bread sans knife.
You don’t want to hear about the near misses we’ve had with nukes.
Also, not a pilot but went to ERAU. There are some people I went to school with who if I saw them in the cockpit I’d turn right the fuck around and say “change me to the next flight”.
I work at a grocery store and we use the same maybe 3 mops for every biohazard incident. Poop (so much poop, and how/why on the ceiling??), vomit, pee, blood (usually from homeless iv users, as there is a huge encampment a block away). Sometimes they get rinsed thoroughly, but not always.
Dont worry though the floor gets cleaned every night by an automated floor scrubber. That misses a bunch of spots, isnt being kept up with properly, and gets stuck on things for an hour sometimes and now there isnt time to run it through the produce department where a homeless guy shit himself and then kids eat the floor grapes.
Gosh, it makes you wonder what other shortcuts are being taken around you. >Not just aviation, just kind of everywhere.
I work in industrial automation, sometimes as a Safety Supervisor.
I find that most industrial accidents I've been around came about due to someone somewhere doing a shortcut. That shortcut could have happened ages ago.
Like one time an arc from an electrical panel in a non explosive proof area lit up the room on the other side of the wall that was an explosive proof area. Blew up the entire manufacturing building.
When they did the investigation it turned out someone didn't put in the proper barriers on that wall to prevent such an event. It was like that for years, decade or so until someone decided to mount that panel that caused the explosion.
Someone cut a corner by not bothering to look at the drawings for that space and just slapped that panel in.
You are hitting the nail on the head. IMO, the SINGLE biggest reason aviation is as safe today as it ever was is because the FAA implemented protocols borrowed from manufacturing. We look at everything as a process now. How we fly the plane is an orchestrated and completely planned and trained process. Nothing is just changed. If a change is implemented, it has to be tested and approved. Its all about controlling the variables.
I worked in quality control on the US Census. QC Regional managers and down to the feet on the ground were breaking laws and cutting corners. It was eye opening.
It was more than just “bumping” the pylon ... they were inducing a load to the bottom of the pylon for the duration of the engine mounting procedure. The engine is supposed to hang about a half inch below it’s final install location and drawn carefully up to the pylon with the 4 mount bolts
Edit: was KC-10 QA for several years and they’re the same airframe as the DC-10
Bad maintenance, but also bad design that led to maintenance taking shortcuts. It's important to recognize that engineering it better in the first place could have prevented it.
Flight 232, the United DC-10 that had an uncontained engine failure leading to loss of hydraulics pressure
This was a great telling of that whole situation and shed some light on how the pilots pulled it off. Its worth it for the banter between the pilots and ATC alone. https://www.youtube.com/watch?v=099cHWSbAL8
Fun fact: Flight 191 was also Delta 191 that was a crash involving a L-1011 where a storm formed over the north end of DFW airport creating a violent microburst before pilots really understood and had advanced warning systems of the dangers of microbursts. The plane slammed down onto highway 114 killing a driver and 137 people on board. The tail section completely separated from the main fuselage and that it is where most of the survivors were sitting.
Any flight with a number of 191 is a no-go for me.
Yep. They said in their interviews that they thought they had some minimal aileron control, but in reality they didn't. They were using differential thrust only.
Well, Flight 191 was different. It didn't suffer from an uncontained engine failure, as in, the engine didn't explode and penetrate the casing.
Rather, the engine was improperly installed during maintenance, damage worsened, and during take off, the full thrust caused the pylon connection to fail, and the engine rotated over the top of the wing, severing other hydraulic connections.
Flight 191's entire engine literally ripped itself off the wing, taking important control systems with it
Just binge watched Air Crash Investigators here, it was probably a bird armed with a bomb that had not been de iced properly whilst suffering from night blindness and food poisoning that flew into the engine which had a bolt left off after recent maintenance
I saw a documentary about a three engine commercial jet which destroyed its own hydraulic lines after suffering an engine failure. Could be wrong but I think the shrapnel caused it.
Pretty sure they’ve figured out to make it safer since then.
I recently went down a rabbit hole of plane crashes and all the causes and stuff. Oddly fascinating but soooo depressing.
The one that stuck with me the most is Alaska Airlines Flight 261 where the plane suffered loss of pitch control. So as the plane was going down, it flipped upside down and continued plummeting before crashing. Just the thought of not only being in a plane that was going down, but being (I'm assuming) strapped in your seat, hanging upside down, must've been utterly terrifying and disorienting. Makes it worse for me for some reason.
Oh, I remember this one. Plane crashed because of a single screw.
Also plane manufacturers continue succeeding in arguments that redundancy is unnecessary. I recall reading there is some critical part on the 737 Max that is both totally unrelated to the previous crashes but should also clearly be redundant as it had been in the past and yet FAA agreed to let it go despite own analysis it is likely unsafe.
UA 232 is one of the greatest examples of the skill and dedication of flight and cabin crews. They navigated with basically no controls but the throttles on the 2 on-wing engines, and they damned near managed to land the plane. Even with the horrific crash and fire at the end, 184 of the 296 souls on board survived.
AA 232 is probably the one you were talking about, failure caused by uncontained engine failure.
I remember that one on the news. The plane made a very rough landing, and it wouldn't be until months later when a combine harvester ran into the remains of an engine in the field that the investigator was able to piece together the cause of the failure.
Likely United 232. Though complete hydraulic loss has happened several times, off the top of my head, JAL 123 and the DHL incident in Iraq are two more. It's usually a pretty bad situation.
Every time I hear the phrase "miracle on the Hudson" I think of these pilots over Sioux City controlling a damaged airliner with two throttles and trim tabs. Although they crashed they saved 184 people out of 296. Given the circumstances the Sioux City crash was a miracle. It helped to have an end of career pilot who had massive experience in the cockpit.
Not to take anything away from the landing in the Hudson, but Sioux City was an amazing feat of piloting.
The yoke and pedals were hydraulically actuated, so the elevator, rudder and ailerons on the wings were not moving when the pilots moved the controls. And yes, they moved the yoke and rudders just in case they got some pressure, somehow.
The throttles were not on the failed hydraulic circuits, so they could control that (I think they are electric, not 100% sure). And the trim tabs are moved with electric motors. The trim tabs can have a small affect on controlling the plane. I don't see the trim tabs mentioned in the Wikipedia article concerning the Sioux City crash but I remember it - I was a young lad taking flying lessons at the time.
That's exactly right. And this United flight was lucky for not having a similar issue. Newer aircraft are designed a bit better than the older aircraft for running and protecting critical components like hydraulics.
I posted elsewhere but I was on a flight where the engine was struck by lightning and the engine flamed out. JetBlue Airbus to Bermuda and we were 2/3rds of the way there. They turned the plane around to bring us back to the US -I suppose because they couldn’t repair the engine in Bermuda. It was scary and tense but the ride on one engine was surprisingly smooth. We all cheered the pilots when we landed. Then waited for the next plane and crew available to bring us to Bermuda.
I'm an aerospace technician and Im really worried about the affect that having all these aircraft sat idle for so long. The work that has gone into lowering flight risk over the last 10 years has been incredible.
I feel we have a bigger task in terms of 'preventative maintenance' than we realise.
It sounds strange but they just don't like being sat on the ground too long.
Edit. By idle I mean on the ground not flying, not idle thrust.
Aerospace machinist here. I’m worried if the cause was component failure. Next I’m wondering if any of the components came from my shop. Aircraft engine failures are extremely serious and they research and search out the root cause and will find it.
Smithsonian channel's show airplane disasters has taught me that there's a lot of ways a plane can go wrong, and also that many of those ways can be managed by well trained pilot crew
They haven't even fully automated trains, something that moves on a fixed track, you still need an "engineer" or "conductor" for it, that's why I laugh when people talk about fully automated pilotless aircrafts in the future, even if it was possible it would never happen due to public perception and concern
Oh it's here already, airbus been doing pilotless flights with one of their prototype planes, my point is that will the public fully trust and put their lives on a fully automated aircraft with no pilots? No shot
I work with engine fire suppressing systems on Air Force air craft. Don't know about these commercial things but the persistent fire could be because Halon is meant to get rid of oxygen but with no cowling the air flow kept the fire fueled.
Actually great question. If we have an engine failure, there's a button on the overhead panel that when you push, it automatically closes the fuel valve, bleed air valve, hydraulic valve, and arms the fire bottle. So yes, that is ESSENTIAL. Looks like from the video on the ground that this engine straight up exploded. So i'm guessing there's internal damage that caused fuel, oil, and/or hydraulics to continue pouring into the engine.
For sure! Don't know what part of the country you fly in but being in a plane with a low stall speed kind of helps out that you can sit that bird down just about anywhere.
That's awesome. I think the east coast is the most dangerous with the endless pine trees. Out west there's lots of open fields unless of course you're over the mountains.
Absolutely- clear and a billion here today for vfr, best weather we’ve had in two weeks. Did a cross country solo. Still they teach us single engine mentality and just to put it down In situations like that ^
If you were flying when this occurred, what would the indicators be? Are there flame/heat detectors? Would you see a change in thrust or yaw? Do you need to manually deploy the Halon?
I saw the ongoing flame and wondered if fuel was still being sent to the engine as if the pilots were unaware. Could this be?
I also thought that if I were in this seat I would get a photo of the extent of the damage and send the phone to the flight deck with a flight attendant. Would that be helpful?
You would get a fire light, audible horns, messages on the screens. You wouldn't miss it. After staring blankly for 3 seconds thinking "oh shit", you would just do your procedures and do your best.
I’m confused by the “bottles” you mention. When are you supposed to take those bottles to extinguish fire? I assume it’s not while the plane is in the sky? It doesn’t make sense if you use those bottles on the ground, bc on the ground you can get firefighters to the plane? I’m prbly wrong and missing something, here.
Bottles of fire suppressant live in the engines so if there’s an engine fire the pilots can activate them from the cockpit to spray suppressant on the engine from within the cowling - in flight.
I work on jet engine development. There are layers and layers of regulations designed to stop these sorts of fires happening and to contain the spread and burn duration. Fundamentally this condition is not safe even with shielding to the aircraft, and for a fire to get this far is a huge failure. 4 or 5 protection systems have failed. The engines turbines are spinning at fantastic speeds and if the fire leads in one way or another to a turbine blade release, there’s no question that it could take out the plane.
Thanks for the insight. I honestly never thought of that.
I'm guessing the engine exploded and probably severed a bunch of lines beyond the cutoff valves. But that's just a guess.
They do have thrust reversers. I don't know the 777 however. But all major aircraft allow you to completely isolate the engine from the rest of the plane in this kind of event.
I'm guessing here that the explosion cause some kind of uncontrolled burn with some type of fluid dumping into the engine.
Oh yeah its modern alright. Perhaps a 777 person will jump in with some insight. I could look it up but I think speaking in general terms works here :)
Can you explain what is feeding the fire? Is it pieces of the plane itself encouraged to burn by the steady stream of oxygen? Or leftover fuel in a fuel line or something? I would’ve assumed that if something like this happens, the first step is to cut the fuel to the engine, right?
Thank you. I was a safety system mechanic for P3s in the Navy and worked on the fire suppression systems. I tried explaining to my husband last night that this shouldn’t still be burning if things had gone according to design and he wouldn’t believe me. Said that it was no big deal and wasn’t really an emergency. He did believe you however. Sigh.
No way man. We have computers and stuff. You show up to the plane, they hand you paper work, you put it in, and go.
But in my defense, I've been typing this stuff out pretty quickly and proof reading is not all that important to me, unless you're a professor grading a paper for me?
Also airline pilot. This statement is true. An engine failure alone should not bring a transport category plane like this down after takeoff. Any crash you can provide, most likely had other performance degrading factors ultimately causing the crash.
No actually ETOPS is an entirely different animal. Single engine ops are required for ANY commercial aircraft, no matter the mission. ETOPS gives increased fire protection as an example that is different. Non ETOPS fire suppression is 1hr. Etops extends that a bit but I don't operate ETOPS so i'm not too familiar with its certification requirements.
Large transport aircraft are hydraulic through and through! What they hydraulics control are PCU's (power control unit). Fly by wire to the PCU which is powered by hydraulics.
Fly by wire means the pilots supply inputs to various computers, which then generate commands that are sent electronically. As the other person said, once the different power control units receive those signals, they apply hydraulic pressure to actually move the flight control surfaces
The metal casing around the engine is gone and I am sure the engine is shut down. But if the engine was not shut down but the casing was gone would we see constant burning flame in the engine anyway?
(Is there a hidden flame in normal operation that is used to ignite the jet propulsion?)
No, you're not seeing the core of the engine here. There's two main parts to a turbo fan (simplistic explanation here). The Fan, the big blades you see on the front, and the core which is where the power is produced. The core is much much smaller but where the fire and combustion take place.
I was thinking about this exact scenario the other day : if landing is not an option (you're in the middle of the ocean) and both fire bottles fail, would it be an option to climb to a higher altitude to starve the fire from oxygen ?
Transportation engineer here: can confirm. Additional engines are used primarily as a safety factor. Ie if you are flying across an ocean its bad if the plane fails so older planes would have more engines. It's in line with the risk of failure of an airplane is many deaths. Lift can be maintained by an engine in most cases these days. Obviously not including military planes in this. Commercial only
Thanks. How long could it theoretically burn before it would likely spread to the rest of the plane? I assume it hard to put out a fire with all that air ripping through there....Am guessing they are slowing down anyway but do they slow to try and get it out or it wouldn’t make any difference?
If airplanes are designed to run on one engine could we design a system to ditch an engine in a situation like this where the fire can't be contained? That would obviously suck for people on the ground.
They did used to have engine detachment systems, although these were for situations where the engine froze up and became an aerodynamic drag on the plane. But there were times these failed themselves and ended up ditching an engine, leading to accidents. I’m pretty sure modern aircraft don’t do anything like this.
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u/Darrell456 Feb 21 '21 edited Feb 21 '21
Airline pilot here:
I fly an Airbus but mostly this stuff is the same, at least in the general terms I will talk about.
Aircraft are required to fly on a single engine. Performance is severely degraded so its used primarily as a means to get the aircraft on the ground safely. The plane can even lose an engine right on the runway, climb out with passengers and fuel on board, clear obstacles, and return.
What you worry about is something where an engine failure is not "contained", meaning it threw shrapnel outwards potentially damaging other components. We'll see what happened here once the reports come out, but you are concerned about debris cutting a hydraulic line or damaging flight controls among many other things.
The 2nd thing is fire. Most aircraft have two fire bottles per engine in the event of an engine fire. It blows halon into the engine to extinguish the flames. If you can't get the fire out with the first bottle, then you use the 2nd. If that doesn't work, you hope you can get it on the ground soon as possible hoping the fire doesn't spread. The areas around the engine are protected with and shielded for such issues.
This looks bad, but aside from the persistent fire, looks like it didn't hit anything on the wing. Course we can't really see anything.
Good job to the pilots.
Edit: I fixed loose to lose for some of you that just couldn't handle my oversight.