When the 777 was designed it showed a little bit of McDonnell Douglas (MD80 MD11) influence when the blade like tail cone was introduced. The A380 looks to have borrowed that same design with the exception of the aft APU exhaust duct. The blade tail cone was found to produce less drag.
The 787 however seems to lack this inovation.
Any body have a clue why?
2007-05-28 03:30:48 · 2 answers · asked by ericbryce2 7 in Cars & Transportation ➔ Aircraft
It isn't really a Blade-tail at all. It is simply a flattened side to accommodate the fully flying vertical stabilizer. With the entire surface of the elevator articulated you need a flat side to mount against. Every plane I know in the current fleet uses the "flying tail". The MD80 does as well but this is mounted on top of the vertical stab. The MD80 probably looks flatter in the back from a distance because of the engine mounts.
But the APU is another story. It is located at the real of the tail pointing upward. The intake is slightly side-mounted in front of the unit but the exhaust is identical to the 777 and others.
A380 tail
http://www.airliners.net/open.file/0867939/M
http://www.airliners.net/open.file/0862443/M
777 tail
http://www.airliners.net/open.file/1145724/M
2007-05-29 01:55:29 · answer #1 · answered by Drewpie 5 · 0⤊ 0⤋
Blade tail cones have less drag, but the side exhaust for the auxiliary power unit is noisier for ground crews. That might be a reason.
2007-05-28 06:20:34 · answer #2 · answered by DT3238 4 · 0⤊ 0⤋