Plane Crashes--Any Pilots or aviation experts?

Wind shear would be a too-common event for some countries and airlines, but that is a close-to-ground event. Beyond that, weather really doesn't cause crashes in major airlines. Bird strikes can do it, if that works. Severe turbulence might if there was a maintenance issue of some sort, or improperly secured dangerous cargo. Volcanic dust is a possibility, though it has caused problems but no major crashes.

Let's face it, excellent weather prediction and radar have eliminated most issues. Airlines just don't blindly fly into hurricanes.

My most believable option would be severe turbulence and partially depleted oxygen canisters improperly stored and handled. Just need some sort of ignition. Value Jet 592 went down in the Everglades for a very similar reason. It's also why UPC's are shipped with disconnected batteries and there are very strict requirements for oxygen generators.

It's virtually impossible to have complete loss of hydraulics. Airliners these days typically have multiple hydraulic systems, powered by either pressure from one or more of the engines, and/or by electric pumps. Redundancy is built in. You'd have to have a complete electrical failure and lose multiple engines at the same time. Bird strikes typically only take out one engine, although if an airliner hits a large flock, more damage is possible. What about uncontrolled cabin decompression? That could be caused by human error, metal fatigue, or systems failure and could potentially incapacitate the crew.

What about the volcanic ash cloud that affected BA009? They landed safely, but at one point all four engines stopped.

To pull this one off, you'd need to put your aeroplane over somewhere with limited radar (and volcanoes, obvs).

What about what happened to the Air France flight over the Atlantic? They got caught in a thunderstorm, I think. And this one that happened around Buffalo was mostly pilot inexperience, I suspect. Even though the plane's computers overcome most mistakes (or deliberate sabotage), the Germanwings crash indicates they don't always.

My husband the general aviation pilot says downbursts are still a major hazard, though radar is better at picking up potential situations than it used to be. But a strong downburst was responsible for that crash in Dallas a few years ago.

Today's commercial transports are, in general, very safe. Other than deliberate human action (terrorism, suicide, sabotage) it usually takes a series of problems and an incorrect reaction from the pilot before the aircraft is lost. As a general rule, every system on the aircraft must demonstrate that it will not fail any more often than once in 10^-9 hours. So you will frequently have 2 or 3 redundant systems for every necessary function.

If you want a believable scenario, however, there are lots of plausible ones to choose from. Poor maintenance practices lead to an engine being taken off the wing for inspection (normal) but not properly reattached and it breaks loose during the flight. Here's an example of a real accident: https://en.wikipedia.org/wiki/American_Airlines_Flight_191 in which everyone aboard died. You'll see from the description that there was the engine separation that ruptured hydraulic lines on that wing, that retracted the slats on that wing, changing the lift capability of the wing, which therefore raised the stall speed of the wing to a speed higher than what the airplane was currently doing, and the fact that the aircraft did not have a good stall warning system all lead to he crash. Removing any one of those factors would probably have allowed the pilots to recover and return to the airport.

Midair collisions do happen, infrequently, again only as a result of at least one error by pilots and/or ATC. Usually several. These are usually fatal to everyone involved, though in rare instances one of the aircraft have been able to land. Here's one: https://en.wikipedia.org/wiki/Überlingen_mid-air_collision where both aircraft were lost and here's another: https://en.wikipedia.org/wiki/Gol_Transportes_Aéreos_Flight_1907 where one plane survived.

A pilot not following procedure or not doing their checklists before takeoff can lead to a crash. One of those happened recently on a business jet. The pilots had quit doing the checklists and they forgot to disengage the gust lock before takeoff. The system should have prevented them from moving the throttles to takeoff power with the lock still engaged, which it failed to do, and the result was a crash that killed all 7 people on board. http://www.ainonline.com/aviation-n...b-faults-pilot-compliance-gust-lock-giv-crash

If you have specific questions, feel free to PM me. I am a flight controls engineer, currently working for an avionics company but I have also worked for an aircraft manufacturer. I'm not a safety analysis expert but I know a fair amount about how commercial airplanes are designed.

There's some good info in this Wiki entry about United 232, the Sioux City crash in 1989. The DC-10 suffered a catastrophic failure of one of the disks in the #2 engine in the tail, and the failure took out all 3 hydraulic systems. The Wiki mentions several other similar events.

https://en.wikipedia.org/wiki/United_Airlines_Flight_232

Hate to say it, but the sky is the limit. Just like car crashes... shit happens. A friend of mine was once re-routed to land with some immediacy (no panic and no explanation during the flight) when severe turbulence compromised the structure. I've been on some rather insane flights in commercial airliners where i'm thinking 'no way'... and my girlfriend is telling me she's been through FAR worse (oxygen masks descending, pilots actually sounding panicked over the com) without incident. I'm sure turbulence has downed more than a few planes over the decades, likely less lately though, as weather prediction, radar and other tricks get more sophisticated.

A relative of mine had to wait for some time, in her seat, while the crew very surreptitiously led a very drunk pilot off the plane (and had to find a replacement). I dont know how often this happens, but pilots drinking is hardly an uncommon concept. What if he hadn't been caught? What was really nuts about this one, was that it was a stewardess that told her this, later on during the flight. This was a couple decades ago.

How about lightning? I'm sure planes get struck all the time, but maybe a particularly savage bolt? I'm just guessing.

Instrument/visual failure? Planes hitting mountains?

Stuff that shouldn't be in the cargo bay, or improperly stored/shipped blowing up? Breaking loose?

There's always snakes... . . . .

It usually takes the 'Swiss Cheese' effect for a plane to crash. This went wrong and that didn't happen and the other got missed and this other thing wasn't noticed and and and. Individual issues generally don't cause crashes - it takes several problems working together to do it. The usual metaphor is you have several slices of Swiss cheese, but the plane only crashes when all the holes line up. The weather is often a hole, but by itself it's unlikely to bring a plane down, and even the most inexperienced airline pilot has a lot of flying experience in general and has passed a lot of exams and checks.

We learn more with every crash, but there's always more to be learned - and in the end, one way or another, gravity always wins.

Ms. Bean said:

Yes! I'm reading a book about his flight and am basing a lot on it, although I worry that because it happened in1989 so much would have changed and no longer be applicable or possible.

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True, but large planes like airliners can be in service for a long time. I was struck last year by something said about the Malaysia Airlines plane vanishing, when people were asking how come we can't track planes minute by minute with the technology we have today? The thing I remembered being said was that every plane is a snapshot in time of the technology available when it was designed and built. You can make superficial changes, but not fundamental ones.

So something that caused an accident twenty years ago might not be able to occur on a plane built five years ago, but might well be able to cause one on a plane built twenty five years ago.

Sometimes, less is more. You may not need to itemise a plausible sequence of sins and omissions. E.g. - if you ended a chapter with the captain proclaiming how much safer the airline industry has become in his ninety years as a pilot, you could start the next with his last-ditch efforts to miss the town he's about to crash into. The reader will fill in the blanks.

One that hasn't happened yet but will sometime - a commercial plane collides with a drone flown by some assclown too close to the airport.

waylander said:

One that hasn't happened yet but will sometime - a commercial plane collides with a drone flown by some assclown too close to the airport.

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That will still have to be exactly the wrong collision and circumstances to bring down a commercial airliner. Not saying it can't happen because it very possibly will, but it may be the third or 15th or 50th collision before the result is catastrophic.

Becky Black said:

True, but large planes like airliners can be in service for a long time. I was struck last year by something said about the Malaysia Airlines plane vanishing, when people were asking how come we can't track planes minute by minute with the technology we have today? The thing I remembered being said was that every plane is a snapshot in time of the technology available when it was designed and built. You can make superficial changes, but not fundamental ones.

So something that caused an accident twenty years ago might not be able to occur on a plane built five years ago, but might well be able to cause one on a plane built twenty five years ago.

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This is both true and not true. Aircraft do get updated with improved components and systems incorporating lessons learned and better technology. Some of these are mandated and some are just suggestions depending on the perceived risk of not making the change. Generally, if the cause of a crash can be identified, steps are taken to update the remaining fleet to better protect those aircraft against a similar occurrence. This could be a human issue like better maintenance procedures or pilot training, or could be the grounding of the entire fleet of that type of aircraft until the parts are replaced, or repairs are made. Or it could be something that can be worked into the existing maintenance schedules if it's not considered likely that the same chain of events could occur again (but there's a mechanical issue that can be addressed). In nearly any aircraft accident summary you read, you'll also see that some kind of change is advised or required to help prevent a recurrence.

> I'm interested in causes related to weather or a perfect storm of problems involving weather.

Air speed readings become foiled after going through a storm; pilots fail to recover from the induced stall.
https://en.wikipedia.org/wiki/Air_France_Flight_447

Boeing flies straight into heavy rain and hail over the Gulf of Mexico.
https://en.wikipedia.org/wiki/TACA_Flight_110

Encounter with a microburst on approach.
https://en.wikipedia.org/wiki/Delta_Air_Lines_Flight_191

747 flies into clear air turbulence.
https://en.wikipedia.org/wiki/United_Airlines_Flight_826

-cb

So true about the drone collision scenario!
Another serious danger these days on approach is when a laser is aimed at an aircraft about to land. Lasers can temporarily blind pilots. Very common to see lasers on approach in the UK. ATC and police take reports very seriously.