CarpeDiem3 0 #1 November 14, 2012 Saw the movie "Flight" with Denzel Washington. More about alcoholism than about airplanes. Darn it. Question. The aircraft malfunction was an elevator stuck in the down position, causing the plane to go into a nose dive from which they could not pull out. So the hotshot pilot Whip Whittaker rolls the plane upside down to get it out of the dive and level off. Here's my first problem. With the elevator still stuck down, while upside down that will make the plane go nose-up into a stall. But it didn't - it flew level. How is this possible? And then as the plane descends for a crash landing, just before reaching the ground he flips it back upright again for the field landing, but the plane flies level without going into the dive again. So how was that possible? If the elevator was still stuck, he shouldn't have been able to pull off those maneuvers. The only way he could have done those things would be if the elevator was no longer stuck, and then he wouldn't have had to fly and crash land like he did - he could have gone to an airport and landed normally. Someone explain this to me... Oh, and that red-headed girlfriend chick was smoking hot. So was the one he was in bed with in the beginning of the movie. Image: http://1.bp.blogspot.com/-85oohPiO5Vc/UI3XONZ7gdI/AAAAAAAAE9Q/J_kINTSJMaI/s1600/flight_image.jpg All the images I can find conveniently cut-off the elevator part of the plane to hide it. Quote Share this post Link to post Share on other sites
theonlyski 3 #2 November 14, 2012 Well, in theory if he rolled it and reduced power, that shouldn't allow it to climb. You can hold an angle of attack at a power setting with a good back pressure (up elevator) and not gain any altitude. Granted, that's on the line of stalling usually, but it can be done and I'd venture to say any certified pilot has practiced slow flight. I don't remember what point he put the flaps in at, but that may have made a difference as well I think. If the elevator was broken free, it doesn't really mean that he still has control over it. "I may be a dirty pirate hooker...but I'm not about to go stand on the corner." iluvtofly DPH -7, TDS 578, Muff 5153, SCR 14890 I'm an asshole, and I approve this message Quote Share this post Link to post Share on other sites
CarpeDiem3 0 #3 November 14, 2012 In the investigation at the end of the movie, they said it was a jammed or broken jack screw, or something like that, which locked the elevator in place. The elevator wasn't missing - it was locked in the down position. And the dive shown was near vertical, so that implies the elevator was full-down. And then at some point, he lost first one engine, and then the other, so he became a glider, and had no thrust to work with to counteract the stuck elevator. Quote Share this post Link to post Share on other sites
billvon 2,442 #4 November 14, 2012 > With the elevator still stuck down, while upside down that will make the plane >go nose-up into a stall. But it didn't - it flew level. How is this possible? If it is stuck down due to mechanical blockage, it's not possible. If it is stuck down due to a broken control cable or half a failed actuator, then reversing the dynamic loading on it might allow the remaining control cable/actuator to regain authority. (Can also be done with trim in most cases.) This is likely based on AA flight 261, although that crash was due to a failure in the horizontal stabilizer trim system, allowing the entire stabilizer to flop around. The pilots in that case did invert the plane to regain control, although it worked only temporarily (40 seconds or so.) Quote Share this post Link to post Share on other sites
pchapman 262 #5 November 14, 2012 Quote Here's my first problem. With the elevator still stuck down, while upside down that will make the plane go nose-up into a stall. But it didn't - it flew level. How is this possible? Ok, I don't know about the movie or the details of how far nose down the elevator was stuck, but one can come up with scenarios where it would fly upside down. The elevator would normally be in a position to trim the aircraft to 1g level flight. ("trim" i.e. - everything balanced in equilibrium) Shove the stick forward, and there'll be a point where the elevator trims for 0g flight. Shove it forward more, and it'll be in trim for -1g flight, so if you rolled it inverted, it might fly level inverted. That's without taking the wing design into consideration. On an aerobatic aircraft, the above might work well. In an aircraft designed for upright flight, the wing will be less efficient upside down, so more down elevator might be needed. So really far forward stick might just trim the aircraft for inverted flight. An added complication is speed stability where the faster you go, the more forward elevator you need to trim, and the slower, the more back elevator (when upright). So in level flight, shoving the stick 3" forward won't necessarily make the plane dive past the vertical. Everything might balance out again at a high speed that the plane can take, or it might accelerate until the plane breaks apart. Depends on the details. Overall that complicates things but could help, for if the aircraft has enough speed stability, if it pitches up a little and slows or dives a little and speeds up, it will tend to return to the original speed and flight path, even with a stuck elevator. It also means that the movie aircraft would trim at some speed inverted, even if not at the original speed. Adjust engine power to find a speed where the aircraft does trim level inverted. (I'm not sure about fuel feed and long term oil feed for typical jet engines inverted though -- CarpeDiem said that in the movie the engines did fail at some point) All in all it sound slike some aspects of the movie scenario COULD work, but getting it all to work together in real life could be tricky, especially for an airliner. There was a famous aerobatic pilot in the UK back in about '70 who had one wing start to fold because the lower joint failed, wasn't wearing a parachute, rolled it inverted, the wing stayed jammed in place (since the broken joint was now in compression not tension). For landing he rolled it from inverted to level at the last moment, putting a furrow through the grass with the wingtip, and skidding it in on its belly before the wing could fold up. That's the only "save it by flying upside down" story I can think of in real life. Small planes have been landed using trim when the elevator disconnected or jammed, but it isn't necessarily easy. The UK case is an example of where the roll back from inverted needs to be done just before touchdown. Whether you can do that with an airliner, its speeds and roll rate, I dunno. If one could even achieve a Sioux City (United 232) type crash, killing a third of those on board, and do no worse than that, that would be a good outcome. (P.S. "AA 261" is Alaskan Airlines in this context, not American) Quote Share this post Link to post Share on other sites
billvon 2,442 #6 November 14, 2012 >CarpeDiem said that in the movie the engines did fail at some point In the real life incident they failed after about a minute of inverted flight, at least per the interpretation of the CVR. >There was a famous aerobatic pilot in the UK back in about '70 who had one wing start >to fold because the lower joint failed, wasn't wearing a parachute, rolled it inverted, >the wing stayed jammed in place (since the broken joint was now in compression not >tension) John J Nance wrote about this incident (as a fictional case) in "Fire Flight." (I highly recommend his books; they are novels about aviation written by a pilot.) Quote Share this post Link to post Share on other sites
kallend 1,653 #7 November 16, 2012 And another thing - during the roll to inverted the full down elevator would cause a turn opposite the direction of the roll, and vice versa to the roll back upright. Agreed - if the elevator is jammed full down and causes a dive under power, it will also cause a dive in a power off "glide". But then again, it WAS just a movie.... The only sure way to survive a canopy collision is not to have one. Quote Share this post Link to post Share on other sites
JohnMitchell 14 #8 November 16, 2012 Quote And then as the plane descends for a crash landing, just before reaching the ground he flips it back upright again for the field landing, but the plane flies level without going into the dive again. So how was that possible? That was my biggest Hollywood moment too. I thought he'd bring it in upside down. When those jackscrews fail, they strip and the whole tailplane is free to pitch up and down. It's very much a single point of failure kind of thing. Years ago a DZ had two pilots (yes, two) flying their new-to-them Porter. After the jumpers left, they pushed the nose over into a beta descent. Some bracket broke on the elevator trim mechanism and they were unable to pull out of the dive. So they pushed it thru to pull out inverted, then were able to roll it upright and find a power setting under which it was controllable. They then drove it onto the runway, holding their breath the whole time. Quote Share this post Link to post Share on other sites
Niki1 1 #9 November 19, 2012 It was a Hollywood airplane. These types of aircraft obey a special set of laws of phyics. Whatever needs to happen to further the story line.Most of the things worth doing in the world had been declared impossilbe before they were done. Louis D Brandeis Where are we going and why are we in this basket? Quote Share this post Link to post Share on other sites
normiss 633 #10 November 19, 2012 Silly people...babbling about the aircraft while completely missing the REAL discussion here. The red head ETA - and the lovely lady in bed is the Latina from My Name Is Earl, isn't she? Quote Share this post Link to post Share on other sites
NWFlyer 2 #11 November 19, 2012 Can ya slap an NSFW on that one? "There is only one basic human right, the right to do as you damn well please. And with it comes the only basic human duty, the duty to take the consequences." -P.J. O'Rourke Quote Share this post Link to post Share on other sites
normiss 633 #12 November 19, 2012 After clicking a link here earlier, my hits on porno sites logged in the corporate web filter server have increased as well. yay. Payback.oh - and sorry. Quote Share this post Link to post Share on other sites
kallend 1,653 #13 November 19, 2012 And another thing! It came to rest in far too short a distance from the site of first impact.... The only sure way to survive a canopy collision is not to have one. Quote Share this post Link to post Share on other sites
CarpeDiem3 0 #14 November 20, 2012 QuoteAnd another thing! It came to rest in far too short a distance from the site of first impact. I thought so too. Would a wingtip slice off a church steeple, or would a church steeple slice off a wing tip? Quote Share this post Link to post Share on other sites
JerryBaumchen 1,068 #15 November 21, 2012 Hi Carpe, QuoteWould a wingtip slice off a church steeple We sliced off the top of a Douglas Fir tree with a wingtip. JerryBaumchen Quote Share this post Link to post Share on other sites
747tech 0 #16 November 21, 2012 QuoteIn the investigation at the end of the movie, they said it was a jammed or broken jack screw, or something like that, which locked the elevator in place. The elevator wasn't missing - it was locked in the down position. And the dive shown was near vertical, so that implies the elevator was full-down. And then at some point, he lost first one engine, and then the other, so he became a glider, and had no thrust to work with to counteract the stuck elevator. If it were a jack screw then it would have been a jammed horiz. stab not elevator which adds another twist to the story. Remember the Alaska Air MD-80 that crashed into the Pacific off the coast some years back? Damaged H-stab jackscrew and jammed stab. Would still say that all the stars would have to be aligned to pull it off. Quote Share this post Link to post Share on other sites
piisfish 135 #17 November 21, 2012 QuoteThis is likely based on AA flight 261do you mean AS261 ?scissors beat paper, paper beat rock, rock beat wingsuit - KarlM Quote Share this post Link to post Share on other sites
evilivan 0 #18 November 21, 2012 QuoteSaw the movie "Flight" with Denzel Washington. Blimey! You are well connected..."If you can keep your head when all around you have lost theirs, then you probably haven't understood the seriousness of the situation." David Brent Quote Share this post Link to post Share on other sites
billvon 2,442 #19 November 21, 2012 >do you mean AS261 ? Yeah, sorry, AS261. Quote Share this post Link to post Share on other sites
Amazon 7 #20 November 21, 2012 QuoteHi Carpe, QuoteWould a wingtip slice off a church steeple We sliced off the top of a Douglas Fir tree with a wingtip. JerryBaumchen Was that a Ralph thing in Orchards??? Quote Share this post Link to post Share on other sites
JerryBaumchen 1,068 #21 November 21, 2012 Hi Jeanne, Quote Was that a Ralph thing in Orchards??? His plane but Danny Gorman (RIP) flying. And yes, in Orchards. JerryBaumchen Quote Share this post Link to post Share on other sites
riggerrob 561 #22 November 22, 2012 I wonder how many Cessna 180s and 185s and early 182s (narrow body) have their jack screws thoroughly cleaned and inspected and greased every year????? Quote Share this post Link to post Share on other sites
riggerrob 561 #23 November 22, 2012 QuoteSaw the movie "Flight" with Denzel Washington. More about alcoholism than about airplanes. ... Oh, and that red-headed girlfriend chick was smoking hot. ... ............................................................................. She is the thirteenth step in the Alcoholics Anonymous process. Can anyone name the fourteenth step? Hah! Hah! Quote Share this post Link to post Share on other sites
kallend 1,653 #24 November 22, 2012 QuoteI wonder how many Cessna 180s and 185s and early 182s (narrow body) have their jack screws thoroughly cleaned and inspected and greased every year????? Dunno about "Brand C", but my Mooney does.... The only sure way to survive a canopy collision is not to have one. Quote Share this post Link to post Share on other sites
billvon 2,442 #25 December 3, 2012 >If it were a jack screw then it would have been a jammed horiz. stab not elevator >which adds another twist to the story. The NTSB investigator referred to it as "the elevator, or horizontal stabilizer . . . ." so they were conflating the two of them. Quote Share this post Link to post Share on other sites
