Comments by "Bo McGillacutty" (@Mrbfgray) on "Viral video provides clues to 747 crash" video.

  1. Once in a great while one of these goes down--and all on Earth hear about it because it is so rare and spectacular.   What other common form of transport can go for an entire yr. without a single fatality in the US?...I bet no on can name one.
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  2. RS Man You seem to have a missunderstanding of what 'stall' means to an airplane--It has nothing to do with engine performance--It's all about the WING.  When a wing reaches a certain 'angle of attack' (that's the angle measured in the direction of air flow/aircraft direction--the angle between the wing and the air flow)  At some point the air is no longer flowing over the top of the wing in a way that the wing can generate efficient lift, the air 'separates' off the top of wing--goes turbulent and the lift suddenly dramatically decreases AND the drag suddenly dramatically INCREASES.  There is only one way to recover (assuming you don't have tons of excess thrust available like some fighter planes might) and that is to drop the nose (as 'all' planes will do by design automatically and as the wing stalls) and regain airspeed and recover at a lower altitude.  This 747 was beginning to recover (it appears) just before impact--it just needed another maybe 1000ft of altitude that it didn't have.  This is why stalls are very dangerous at low alt.
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  3. jimmywacked  Yeah or sliding around on belly...those are both common ways of getting around. 
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  4. RS Man Clarification:  Engine failure can LEAD to a stall of the wing just as anything that slows the plane down can but that's not what happend to this 747 apparently...it simply had the nose way to high...climbing steeper then it could maintain proper air speed/flow over the wing.  It is likely that the cargo broke free and rolled aft making it impossible to lift the tail up and maintain a sustainable climb rate. (or the cargo center of gravity was grossly missplaced to begin with perhaps) So as it slowed down the pilot wants to give down elevator to reduce climb rate and keep adequate airspeed but the weight was too far back--nothing is much more dangerous then an excessively tail heavy aircraft.  Or it's possible that the pilot just screwed up really severly and ignored stall warnings and deliberately held the nose much too high, but that seems highly unlikely as it's a unbelievably stupid mistake with consistently deadly consequences this close to the turf.
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  5. RS Man One more thing:  It does happen rarely that ONE engine of four will fail, for more then that to fail at the same time is exceedingly rare unless flying thru volcanic ash or hitting a hundred geese, or running out of fuel or something like that, and even if a 747 loses any 2 engines on take off (the worst possible time) it can safely climb out gradually and go around to land.  It might have a chance even on one engine alone depending on circumstances. 
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