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Old 6th Dec 2010, 14:47
  #112 (permalink)  
bearfoil
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DERG

On page 70 there is a "Slice" through the TRENT and with it a graphic that shows the LP and IP rotating the same direction, it is the HP that contra rotates, as I view it. A bone to pick with an earlier drawing that shows trajectories out the case of The IPT. The trajectories begin above the axis of rotation. If that is accurate one assumes the Projectiles would have exited to port.

Ferpe's schematic might be the TRENT 700. If the oiling is similar on the 9, take note of the "coupling" at one end of the stub pipe shown by arrow. If it is a couple, the end presented as the stub pipe in the "pics" may be the penultimate opening of the delivery tube, this would indeed provide an explanation of what I see as "Wear" rather than manufacturing "Defect".

The TRENT 700 is 2000 pounds lighter than the GE carried on some 777 airframes, it is this lighter weight that was a selling point for Operators of the TRENT on this Boeing. DERG, light weight is quite important in this accident, as it was in BA038.

One of the contributing factors to the Fuel starvation in 038 was vibration on Thrust select on short final. It is "known" by the AAIB to have shaken loose "Migratory Ice", that impacted the FOHE, causing cavitation and spool down.

Here, with QF32, vibration seems to have been a factor; another would be mechanical stresses focused on this "Connection" feed to delivery. The arrowed oil tube is supplying the dual roller bearings at LPT, so it may not be the correct "Stub Pipe", in question.

DevX has responded emphatically re: "Drawing". My request would be of him to supply a picture (of the TRENT 900) isolating the "stub pipe" in question, to determine if indeed the end shown to the public is one half of a "Quick Couple".


Once again, I note tube architecture that suggests other than the delivery end of an oil supply system, and that the damage appears to be Wear, not "Bench Numpty".

Ever ready to occupy the end of the "Limb", I will say the loss of oiling was caused by the severing of the supply line from the delivery line. I have seen fluid couplings fail with that signature under seriously more docile environments than TRENT @ max chat. Standing to be corrected. Anybody?

bear

Last edited by bearfoil; 6th Dec 2010 at 15:39.