reply to post by Cade
Because the fuselage is actually much stronger than the engines are.
That is the keel beam of an A320. That is the strongest part of any aircraft. Pound for pound, aircraft aluminum has a higher tensile strength than
When the 757 hit the Pentagon, the hollow portions of the fuselage began to disintegrate. What punched a hole in the building was the keel beam, and
the more rigid portions under the skin of the aircraft.
As for the engines, as Waynos has stated, they are not the solid pieces that you think they are. Most of the weight of the engines is in the cowling,
and fan sections. The core of the engine is dense, and it's heavy, but by the time it would have gotten to the wall, the fan section and the cowling
around it would have absorbed most of the energy of the impact, and slowed the core down to where it wouldn't penetrate the concrete.
If you look at the engine of the KC-135R, which is the workhorse of the Air Force tanker fleet, it looks like it's a really big engine. It's big
enough for a man to stand up in the intake. But if you look at the core of the engine, it's actually tiny.
The same applies to the 757 engines that hit the Pentagon. Six tons sounds like a lot of weight, and they look like pretty substantial engines, but
they're actually very small, and surrounded by what is basically a big crumple zone in the cowling, that will absorb a lot of the energy of impact,
and prevent the core from penetrating.
edit on 11/27/2012 by Zaphod58 because: (no reason given)