What caused hijacked Flight 93 to crash?

It crashed in a rural area of Pennsylvania on September 11. What caused it to go down when it did?

Nobody knows for certain, though the investigation revealed no mechanical or electrical failure. The most likely theory is that the plane went down either during a struggle between passengers and the hijackers, or because of such a struggle. Whether the passengers forced the plane down to prevent the hijackers from using it for their intended purpose, or they simply lost control is unknown. Read about it here.

I think we shot it down.

Fighter jets were scrambled after that plane. Reporters were giving updates continuously, anticipating where the plane was heading, etc., then all of a sudden, they went silent about it. When they mentioned the plane again, quite a bit later, it was to say it had crashed. No mention of the jets that had been chasing it.

IMHO, I don’t think the powers that be thought the American people could handle the idea of our fighter jets shooting down a civilian aircraft, despite what had already happened at the WTC and the Pentagon, and the truth was quashed.

Tradegy enough, it’s more comforting to believe that heroic actions by the passengers brought the plane down than to know that our military shot it down.

In GQ, people are looking for factual answers. Do you have any credible sources supporting your theory?

Go here

Snopes on the subject. Like me, they say we do not know for certain what happened.

I’d hardly call that credible.

CBS news reported that the two F-16 fighters scrambled to pursue Flight 93 never got within 60 miles of the doomed airliner before it crashed, well beyond the range of any air-to-air missiles. But they had orders to shoot it down if it refused to divert away from Washington.

According to this, the AIM-54 Phoenix Missile has a range of about 100 nautical miles. This particular missile is exclusively carried by the F-14 Tomcat, according the the article, but I don’t see why some other similar missile couldn’t be carried by the F-16.

The Phoenix was, IIRC, designed specifically for the F-14. For whatever reason nothing else can be mounted on the pods closest to the engine nacelles. It’s also a really damn big missile, and probably too heavy for the F-16. According to this, the only air-to-air missiles which can be mounted on the F-16 are the Sidewinder, AMRAAM, and Sparrow. None has a range greater than 30 n. miles.
Even export F-16s don’t carry anything that size. The HARM missile has a range over 80 miles, but is for ground attack.

Duckster, the mirror is not a credible source in the eyes of anyone other than cabbies, truck drivers, and Members of Parliament.

Just chiming in to say that RNATB is correct about the Phoenix: it was designed specifically for and carried only by the F-14. F-16s never have been able to carry this weapon, and probably never will. The Phoenix is a radar-guided missile and was tailored to the F-14s radar system, which is capable of tracking and firing against six targets at once. The F-14 RIO (Radar Intercept Officer) handles all of this, whereas the F-16 is a single-pilot machine and relies on “fire-and-forget” technology wherever possible.

The article in The Mirror can be debated elsewhere.

i have wondered about a factual question that a pilot could answer: what happens to a plane if the pilot stops actively flying it? assume for the sake of argument that the passengers either got to the cockpit door and the hijacker pilot stood up to resist them, or that the passengers actually got into the cockpit and pulled the bad guy out of his seat. would the plane have gone out of control immediately, or would it have maintained level flight until someone did something with the controls (i’m assuming that the autopilot would be off)? does a modern airliner have any mechanism that would automatically try to stabilize it if it begins to go out of control? apparently at least one of the passengers was licensed to fly small planes. if the passengers been able to pull the hijacker out of the cockpit, would a recreational pilot have had a chance of keeping the airliner in the air? (i have no opinion about the larger question, i’m asking about how the plane works.)

Absent rudder or stick inputs, most jetliners will automatically assume level flight. Unless the plane was in a steep climb or dive when the pilot stopped flying it, I think it unlikely that the plane would have crashed just because nobody was actually there.

IMHO, the possible scenarios are:
-pilot deliberately crashed plane to avoid hijackers taking control
-passengers deliberately crashed it after seizing control
-hijackers deliberately crashed it because of a passenger uprising or possibly in a moment of contrition or somesuch
-a struggle in the cockpit either damaged the avionics, extended the flaps, or shut off one or more engines

Frankly I seriously doubt that the plane would have been shot down even had the F-16s been capable of doing so. The plane was at least half an hour from any likely targets, if I recall rightly, and the fighters would have attempted to force it down or at least make contact before shooting it down.

“Steep climb and dive” are pretty relative terms. An airliner will hardly ever exceed 10 or 15 degrees from level; it would feel to the passengers as if the plane were flying straight upward (or down). Of course, a 757 in a 10 degree dive would probably take longer to pull out of it than, say, an F-15 in a vertical dive.

Jomo Mojo, your OP has been asked before several times over the last couple years. For your edification (and because I hate to repeat myself over and over) please peruse the following SDMB thread:

Fourth Hijacked Plane Shot Down?

Moving right along…

It depends on several factors, including the type of airplane, mode of flight, whether or not an autopilot is engaged, and weather.

Please keep in mind I fly small piston-engine airplanes. Pilot141 flies the big iron and may well be along to flesh out the pertinent details about those.

Remember that airplanes follow Newtonian physics. If they’re in motion then tend to stay in motion. Then tend to continue along their course until something alters that course. So, in cruise flight, assuming the airplane is optimally trimmed (that is, adjusted for maximum efficiency and minimum need to fuss with stuff) and the atmosphere is calm, if you take your hands and feet off the controls the airplane will tend to continue at the same speed, altitude and heading. Even if you don’t have the autopilot on. Even in small airplanes, in calm air, in cruise, you can take your hands off the controls for a minute or two to pull out a map, check your flight plan/clearances, put on (or take off) your sunglasses, sip your coffee, or otherwise tend to chores. If there’s an autopilot, depending on the sophistication, you can take your hands off the yoke and watch the airplane fly itself (actually, if you’re using an autopilot you’re supposed to keep an eye on it, just in case of malfunction). For the big passenger jets it’s the same, but more so - although not done in normal circumstances it is possible to set a big jumbo up to happily fly itself for a considerable length of time unsupervised. Their flight control systems are sophisticated enough that the pilot(s) can program the airplane to take off, fly to a destination, and land itself. That is, of course, dependent on the proper instructions being set up in advance.

That depends on what was being done with the controls when the bad guy was yanked out of his seat. If the plane was set up to fly straight-and-level (even without an autopilot) that is what is would tend to keep doing. If it was in a turn, it would tend to keep turning - but in a turn it is also more likely to start doing something weird. If climbing or diving it would tend to continue doing so.

However, there is a considerable difference between gently releasing the controls and standing up, and being yanked bodily out of your seat. You tend to resist being yanked. You tend to hang onto things in such circumstances, like the control yoke. I think it would be very difficult to remove a resisting person from a pilot’s seat without the controls being pulled, pushed, or otherwise jostled - in which case the plane may start doing some very odd manuvers.

A note about autopilots - they are supposed to disengage automatically when the controls are moved past a certain point (this allows for sudden evasive manuvers - such as avoiding hitting another airplane - without the pilot needing to worry if the autopilot is on or off). I would expect these limits to be exceeded if the pilot is fighting to stay in his seat, or being dragged out of it. So even if the autopilot had been engaged I wouldn’t expect it to stay that way during a fight for control of the airplane.

Well… that’s sort of an autopilot function but since it’s unlikely for the autopilot to be engaged in such a scenario… Passenger jets are designed to be stable aircraft that fly straight-and-level. Now, my experience with small planes has involved some models that, as an example, if put in a gentle turn and the controls released, will gradually stop turning and return to level flight without any human intervention. It’s built into the design. Now, I don’t know that much about big jumbo jets, but they could likewise have similar stability built in. However, this only works up to a point. Even the most docile and stable airplane can be provoked into wild gyrations what require quick thinking and a skilled human to correct.

Actually, the passenger in question had a commercial pilot’s license. Even so, without jet experience (which, apparently, he did not have) the answer is almost certainly “no”. This question has also been asked:

By the way, is there anyone on board who knows how to fly an airplane?

Isn’t this essentially what happened with Payne Stewart’s plane? IIRC it only crashed once it ran out of fuel.

Airline pilot here.

Broomstick covered the gist pretty well, but mis-estimated the severity a bit.

If the autopilot was on and the hijacker was gently removed from his seat the airplane would keep doing what it was doing. If that was straight ahead & level, then so far so good (see below). But if the autopilot was set up to be descending at that moment, then it’d keep descending until it hit the ground.

More likely, the autopilot would be disconnected either before the hijacker was (hypothetically) pulled from the seat, or it would be disconnected by all the associated thrashing.

Now you’re in a world of of hurt.

An airliner is stable, but the controls are a lot more responsive than a small-plane pilot would expect. One decent jolt to the yoke (“steering wheel”) and everyone would be bounced off the walls or ceiling. That’ll produce a lot of panic and confusion in a big hurry.

Beyond 30-ish degrees of bank an unpiloted jetliner is likely to continue rolling until it’s more like 90 degrees of bank and then the nose’ll drop and now you’re screaming towards the ground, gaining speed like mad. Within literally 10 seconds you can go from “we’re fine” to “real pilots would have their hands full.” At 20 seconds the wings peel off the plane. At 40 seconds you arrive at ground-level.

Even at more moderate bank angles or descent angles, it’ll be next to impossible for anyone to climb into the seat and get the situation under control before it becomes unrecoverable.

Egyptair had a plane crash a few years ago about 10 minutes after takeoff from JFK. The (controversial) probable cause was that the co-pilot committed suicide. The significant point here is that they went from “fine” to “diving and shedding vital parts and dead” in about 45 seconds. And the trained Captain in the cockpit couldn’t prevent the event.

In the movies these things take a long time, with lots of meaningful grim looks and time for witty tough-guy banter. In real life, its a lot quicker.
Could a lightplane pilot “fly” a jet? Sort of.

The hijackers “flew” 3 of the 4 airplanes successfully for 20-40 minutes with only lightplane and microsoft flight simulator experience. Given an airplane flying straight and level with the autopilot on and a calm, mentally together, lightplane pilot, he/she could sit there for 5 minutes getting their bearings, then gingerly try gentle banks and climbs and speed changes, working up to being able to remain in control through normal manuevers.

In good weather in familiar terrain they could probably get the airplane pointed at an airport. Landing? Probably not. Given enough fuel they could keep trying until they succeeded, but one of the hardest things they’d have to teach themselves is what’s OK and what’s not. With no standard of comparison for acceptable deviations, they’d like as not paint themsleves into a corner before they realised it on the 1st or 2nd try and crash.

I don’t mean to make flying jets sound like some insanely difficult job; it isn’t. Given 3 or 4 hours in a real jetliner simulator with an airliner instructor, most currently active lightplane pilots could probably be taught to do an acceptable good-weather flight and landing.

But teaching themselves in real time (under no small stress) ain’t gonna work in 99.9% of the cases. The task is 100% real-time and we all know how much slower we are at something, anything, when we’re just learning. Without practice, the jet’ll be offering things-that-need-doing faster than the would-be pilot can do them and pretty soon they’ll be dead.

I agree that a pilot who has only flown small airplanes would certainly crash if he/she attempted to land an airliner on his own, but suppose they managed to overpower the hijackers and this passenger/pilot takes over while the plane is straight and level. There would be several hours of fuel on the plane, and ATC would have time to get an experienced pilot of that type of plane on the radio. With a lot of back and forth talk of airspeeds, flaps, power settings, angle of attack, isn’t it possible that the passenger/pilot could be “talked down” to a successful landing? (Especially if he had experience shooting ILS approaches)?

Sorry if I missed this;

Was the data from the flight recorder analyzed? What did it show?

When was communication cut off from the ATC`s?

Can the ATC force a mic in the cockpit to transmit sound??
(This way if the cockpit doesn`t respond they could listen to what was happening in the cockpit.)

I hope I’m not violating any rules by posting a link to another forum, but there was a huge, years-long debate about this on airdisaster.com… Basically there was a conspiracy theorist who threw out every possibile idea and a bunch of people who debunked it, punctuated by a some pilots and military people who tried to give their best interpretations of the evidence. It’s a long, LONG thread, but it’s worth looking through if you want to get an idea… Of course as far as ANSWERS go, it all boils down to no one really knows…


Airdisaster.com is a pretty cool site, though, for finding out about airplanes and what happens when things go wrong on them. Lots of people in the business, from pilots to controllers to investigators.