*Some* of the hijackers were minimally-trained pilots. Those aboard Flight 93 may have gotten the right one.
It also appears that the terrorists aboard Flight 11, the one with Mohammed Atta aboard, hedged their bets.
-archy-/-
I would like to know exactly what the "advise" was. Note that Mueller did not say "fly the plane into the ground". He said "crash the plane".
One of the hijackerrs had a bomb around his waist. This was reported by the passengers in their phone calls.
Perhaps the instruction was to detonate the bomb. This would crash the plane and end the passengers' heroic assault.
Speculation: this information will eventually be confirmed by the government. They still don't want you to know the hijackers had bombs because TSA still cannot keep bombs off planes. Hand searches of luggage will not find bombs and there aren't enough bomb sniffing machines at airports yet. When the travelling public is better protected they will release the complete story of Flight 93.
Also, a few days ago the feds issued a warning about ordinary objects hiding knives and bombs and renewed threats to the air industry.