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Old 28th Mar 2009, 09:00
  #301 (permalink)  
GMDS
 
Join Date: Feb 2007
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What of the MD-11? What makes a "pilot's airplane"? Is it a plane for men with above average skills who love to demonstrate same? No slight intended to those who like that sort of thing, and no slight intended to those who've identified it as a pilot's plane
I hate these misconceptions.
Like the smaller stabilizer : If you compare a 747SP with a -300, you will notice a bigger tail ... because there is less leverage, so you need more surface, simple physics. Same applies to the DC10 and the longer MD11 with the stabilizer, no mystery there. As for the aft CG, .. well with a trim tank you can vary the CG, so it might be aft, but for TO and LDG it will be forward as in other aircraft. Some astronauts blocked the auto-re-transfer as to keep it back longer, forgot it and nearly crashed. Maybe the myth comes from this.
Now to the landing characteristics. They are not good, agreed. When someone says it needs a REAL pilot, it's partially true, but only because too many newer pilots never had the chance to learn to fly this kind of aircraft. They were bread on Airbus et al. The reasons for this difficult behaviour was mainly: High surface load and a steep increase of the power-drag curve below Va. The only plane that was worse, was the DC-9-50, with a surface load higher than a fighter jet! Pilots coming from the DC-9 series and well trained in pitch/power flying never had big problems with the MD11, those coming from the A320, ... lots. Even old DC9-50s had the hard landing tendency, allthough with the main gear behind the centre of rotation, it did not result in bouncing, rather slamming the nose wheel into the ground.
The most important thing on approach with a MD11, was to keep it as stable as possible in pitch and speed, above Va. Funnily enough, this proved to be a challenge for many pilots. They often had huge pitch variations, therefore thrust variations, constant mistrim and finally speed excursions. As the beast has very high approach speeds, no one liked this too much on shorter runways. If you found yourself in a slight overspeed correction close to flare, with low thrust and increasing pitch and the trim anywhere but where it should, the hard one was assured. Pulling hard might help, but as this resulted in ugly pitch up landings, the LSAS got programmed to dampen the hard up-input. I suppose that this might be a co-contributor to some hard landings that resulted in bounces.
If you manged to keep the pitch nice and stable, to keep the speed above Va by helping the AT a little (especially keeping it up a notch below the 50' retard command), if you defended the GS nicely right down to minimum and applied the aiming point landing technique, even in strong crosswinds and windshears, the MD11 was really ok.
BUT: These should be basic flying skills for Ailine pilots, shouldn't they?????? (no comment)

Again, aerodynamically the MD11 was not the jewel in the crown, but it was absolutely managable in the same enveloppe as the other brands.

(The cockpit layout however, I can't resist to add that, is still light-years ahead of any Bus or Boeing)
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