Saturday, December 4, 2010

Rolls Royce engine failure, followup

Aviation Week believes the catastrophic in flight engine failure suffered by the Trent 900 engine was caused by an oil leak. The engine oil leaked from a piece of tubing, pooled in the bottom of the the engine casing and caught fire. This is back in the hot section of the engine, there is plenty of heat to ignite darn near anything. The oil pipe leaks are attributed to welding flaws at the factory. The extra heat of the oil fire caused the intermediate turbine to run too hot and fail. Jet engine turbines always operate as hot as engineering dares, the hotter, the better the fuel economy. It wouldn't take much additional heat to push the turbine over the temp limits.
If true, this is good news for Rolls. They merely have to inspect all the engines for oil leaks, and replace some engine piping. The basic design of the engine appears to be OK, it just had a weak part installed. Change out those parts and problem is fixed. There should be some hearty sighs of relief coming from the Rolls engineering dept.


Parag said...

Two different kinds of engines are used to power the fleet of A380s; the one that came apart near Singapore is the Rolls Royce Trent 900. Like all Rolls Royce engines, the Trent 900 adds another set of compressor blades into the mix, the so-called Intermediate Pressure (IP) compressor. Instead of squeezing the air in two stages, the engine does it in three.

Dstarr said...

Yes indeed, and that is the great danger to Rolls, the corporation. Future A380 customers can specify American engines rather than Rolls Royce. After the Quantas engine failure, I'm certain that many airlines are thinking hard about buying American.
BTW, Aviation Week had a picture of the oil plumbing gizmo that failed. It's a machined part, and one of the holes was bored off center, thinning the wall, which burst. It's clearly a manufacturing goof, lack of quality control, rather than a design goof.