Aircraft On Fire at Ohare

a reply to: roadgravel

Oh, this is scrap. They'd have to replace the center wing box, both wings, the horizontal stabilizer on the right side, and the aft fuselage plug.

a reply to: Zaphod58

Given what is shown in those photos, not surprised the damage was extensive. Looked really hot.

a reply to: roadgravel

One piece of the turbine came out through the cowling, crossed a runway, a taxiway, and embedded itself in the wall of a building a half mile away. They're damn lucky it didn't go through the cabin.

a reply to: Zaphod58

So true. When I heard about the 1/2 mile I did had that thought about the cabin. In flight, it like a roll of the dice.

The right hand second stage HPT fractured into four pieces with the engines at full power, as the aircraft was passing through 128 knots. The aircraft was at 134 knots when power was retarded and brake pressure began to rise. It took 25 seconds to stop the aircraft.

One of the fractures showed signs of a fatigue failure and began at an inclusion on the forward side of the hub.

airwaysmag.com...

a reply to: Zaphod58

Doesn't this bring all this model engines into question of possible future failure.

a reply to: roadgravel

It sounds like there was a defect in the disk. It would be a matter of inspecting the disk on high cycle engines. The HPT disk has a life cycle of 15,000 cycles, this disk was at 10,984.

This type of engine is in use on quite a few aircraft, and this makes the first HPT failure since it entered service.

Given one defect, it's seems possible of at least a few more parts manufactured near the same time, being defective.

A bit scary. Hopefully it was just one for some reason. I imagine inspections will be required for at least some engines, correct?

a reply to: roadgravel

It was a defect that caused the #2 engine on United 232 to come apart, but that was the only one. It all depends on what caused it. There was a turboprop aircraft that had the prop come off and embed in the wing, because of the cleaning process for the engine and prop. In that case, they found several engines with issues.

They'll probably end up mandating inspections beyond a certain number of cycles, which will require borescope inspections.

Thats not an inclusion,thats a bl00dy blind person on the Quality control line..Cant believe they missed that nugget..

a reply to: Blackfinger

Unless it was like the one on United 232. That one started inside the turbine and couldn't be seen until shortly before it shattered.

Multi axis Xray needed?

a reply to: Blackfinger

Ultrasound before initial installation.

GE has recommended ultrasonic inspections of the first and second high pressure turbine disks produced before 2000, in their CF6-80C2 engines. New documents show that the second stage HPT disk ruptured, due to cracks that formed from an "anomaly" under the surface of the disk. The pilots reported reaching 80 knots, and then there was a "ka-boom" from the engine and a bump. Fragments from the ruptured turbine went through the dry bay above the engine, and ruptured the main fuel line, allowing the fire to start.

www.flightglobal.com...

Looks like Trents are going the same way..
Thai grounds 787 fleet

a reply to: Zaphod58

Sounds like that DC-10 that crashed in Sioux City in the late 80's. A defect in the turbine disc caused a failure. when the engine came apart it cut the hydraulic lines for the rudder and elevator.