A PT-6 engine spins at about 42,500 RPM (makes it easier to understand why parts can come out the side of a case). Anybody know what the RPM of a Garret is? I don't ever remember hearing a number. I assume it is close to the same, although if memory serves correctly a cintrifugal compressor (garret) is more efficient than an axial flow (pt-6) (please correct me if I am wrong). I will try to ask in school monday what a CFM spins at (GE engine found on some Boeings, and Airbus's). Typically we just learn RPM as a percentage.
The AA 767 threw an entire compressor disk. It also severed one or more fuel tanks. If memory serves they said the airplane would be a total loss. Airplane had rejected a T/O cause it couldn't make power. The mechanics were maintenance running it when it let go. (no pax on the plane)
You are correct the thickened skin on an Otter is for ice.
The DC-10 report is a wonderful read, if you have the opportunity listen to Capt. Hanes speech on the event. I agree the guy was a hero. Also someone was watching that flight. The area hospitals were inbetween shift changes, IE double staffed, National Guard was on maneuvers, and the airport had just recently done a disaster drill. Makes even a heathen like me think.
It takes more than just an engine failure to trigger an NTSB report. If the aircraft ended up not having a "successful" landing afterwards, or if there was a passenger that got "hit" by the shrapnal then it probably would. Going off memory it requires overnight stay in a hospital, broken bone, loss of limb, hearing, sight, or $20,000 of damage to trigger the NTSB. The engine expense alone will not trigger the $20,000 threshold, airframe damage, or something it hit would.
Mark