An American Airlines Boeing 767 experienced a high power engine failure during testing at LAX airport. The high pressure turbine disk in the #1 engine ruptured, puncturing the left wing and fuel tank. It then sliced through the belly of the aircraft and damaged the #2 engine. The wing puncture caused a major fire that engulfed the wing and rear fuselage before being put out. The extensive damage means the aircraft will likely be declared a total loss. General Electric is investigating the cause of the uncontained engine failure.

1. American Airlines Boeing 767
12:30 PM, Friday, June 2, 2006 at LAX
Doing a high power engine run had a #1 engine HPT
failure:
- HPT let go and punctured left wing, #2 engine
- peppered fuselage and
- set fire to the aircraft.
The turbine disk exits the engine and slices through the
aircraft belly and lodges in the outboard side of the #2
engine.

2. Sounds like GE are trying to hush this up. I think I
might have browned my trousers if I was looking out that
charred window!
Happened to an AA 767 last Friday. The disc went
through the aircraft into the OTHER engine.

3. I'm not sure whether you will have heard about this as it
appears to have been hushed up over the weekend. On
Friday during a ground run at LAX, GE CF6 in the number
one position let go on an American Airlines 767. Two
taxiways were closed while bits of disc were retrieved.
Attached are some photos, one of which shows half a
disc sticking out of an engine. In fact, the disc belongs to
the other engine - it's passed through the centre wing
box and embedded itself. The rear fuselage and port
inboard flaps were toasted as combustor exit gases
escaped and hit the airframe, which has to have been
written off. Interestingly, photos of it were uploaded onto
various websites on Friday evening. As of this morning
almost all of them have gone, including any of the aircraft
as a whole. This obviously has some pretty serious
implications for twin-engined aircraft.

4. General Electric is investigating the cause of an
apparent uncontained engine failure which caused
extensive damage to an American Airlines Boeing 767-
200 at Los Angeles on Friday.
The aircraft (N330AA) was undergoing a ground run-up of
the (left) No.1 engine when the problem occurred. The
CF6-80A was being tested after the crew bringing the
aircraft in from the New York reported abnormal power
response from the engine during the flight.

5. © Los Angeles Fire Department
Reports say the engine was at more than 90% power
when the failure occurred, either in the shaft or the high
pressure turbine (HPT) area. Judging by images of the
incident that have since appeared on the Internet, it
appears that an HPT disc ruptured, puncturing the fuel
tank in the wing near the trailing edge, slicing partially
through the belly of the aircraft and damaging the keel
beam. The No.2 engine was also damaged by the
exploding debris and the fuel tank on the right wing
punctured.

6. The wing puncture also caused fuel to be spilled on the
tarmac, and that along with a fuel line rupture caused a
major fire which engulfed the wing and the rear fuselage
before it was put out. Fortunately a Los Angeles airport
fire department was close by, and got the fire under
control while the the maintenance crew escaped The
damage to the wing trailing edge, flaps, aft fuselage, fuel
tanks on both sides and the keel beam makes it likely the
aircraft will be declared a write-off. The surrounding
runways and taxiways were closed off for some time
immediately after the incident while a FOD search was
carried out. Parts of the second HPT disc were reportedly
still missing as of yesterday.

7. The CF6-80 has been hit by similar issues in the past, and
as recently as January 2003 was the subject of a US
Federal Aviation Administration airworthiness directive
(AD) calling for inspections of the HPT disc. The AD was
prompted by an incident on 8 December, 2002, when a
767-200 equipped with GE CF6-80A series engines
experienced an uncontained failure of a stage 1 HPT rotor
disc during climb. The FAA said at the time the "results
of the investigation indicated that the stage 1 HPT rotor
disc failure was the result of a crack that initiated in an
aft corner edge of the bottom of a dovetail slot. The crack
propagated in fatigue to critical crack size, and
subsequently resulted in disc rupture and separation."

8. The FAA also notes that in September 2000, a U.S.
operator experienced a similar uncontained failure of the
stage 1 HPT rotor disk during a ground maintenance run
of a CF6-80C2 engine. Again it said "the investigation of
that failure had indicated that a crack initiated in the
dovetail slot bottom aft edge. The root cause of the crack
initiation remains unknown.
However, cracks, burrs, or damage sustained in the
dovetail slot bottom corner radii from improper handling
and processing during new part manufacture and/or
during maintenance were suspect for the September 2000
event.“.
A previous AD, which became effective in June 2001, was
also issued to mandate inspections of the CF6-80C2
stage 1 HPT rotor disc dovetail slot bottoms.