Mr. Vortex,
I have been reading the B727 FCTM and it said that the B727 can't
recorver it self from the dutch roll condition at high speed & high altitude.
You mean the pilot can't recover the plane, or it simply will get progressively worse (dynamic instability) without any pilot intervention
Is that true? What make the B727 unable to damping the dutch roll?
Small rudder surface of B727? or large swept wing angle?
I think it has to do with the combination of wing sweep-angle, and the T-tail configuration.
Also, does any of you have ever firewalling the throttle? Is it increase the thrust significantly more than the takeoff rating?
I'm not a pilot, but I can tell you that during virtually all commercial airliner takeoffs are not done at 100% power; they are done at a reduced power settings which still allow the airplane to get airborne, and climb purposefully, yet increase engine service-life (as well as reduce noise).
Fire-walling will push the engine past 100% RPM -- it is a setting only used in emergencies such as a stall, or in windshear. Being that the engine is pushed past its normal maximum operating RPM, an inspection is generally done after something like this is done.