Original posting by tdracer:
Two -80A disc failures occurred during ground runs - one ground run failure resulted in the 767 burning to the ground (USAir IIRC).
The other one I recall is this one at LAX:
An explosion that ripped apart the engine of an American Airlines 767 during a ground test at Los Angeles International Airport was far more dangerous than first reported, new details suggest.
The blast was strong enough to hurl an 18-inch chunk of metal disk more than half a mile -- across taxiways, service roads and two active runways. Airport workers found the piece two days later, not far from the airport's perimeter fence.
The pilots on the incoming flight reported a vibration they couldn’t quite figure out the source other than one of the engines. So rather than remove the suspected engine from the wing for examination, it was decided to attempt to duplicate the vibration on wing.
Workers were still trying to figure out what was wrong with the airplane when they pushed the throttle for both engines to high power, and one of them blew apart.
The explosion outside the American Airlines maintenance hangar on June 2 sparked a small fire that sent a column of dark smoke over the passenger terminals at LAX and drew most of the initial attention. The explosion -- officially an "uncontained engine failure" -- gutted the engine and blackened part of the airplane's fuselage. Part of the failed disk traversed through the fuselage doing substantial damage and into the other engine.
It also blasted pieces of the damaged engine onto a nearby runway -- and, in one case, clear across the southern airfield. The workers who found that piece half a mile away described it as a wedge of metal, 2 inches thick, and heavy.
The aircraft was written off as a total loss.
The problem were tiny cracks that had developed in the edges of the fir trees of the disk holding the stage 1 HPT blades. These cracks became apparent near the end of the life of the disks, but before removal from service.
