Bearfoil has been questioned for stating a senario in which a spline lubrication problem is the cause, to wit:
bearfoil - I'm not sure that I understand the thrust of your latest thoughts.
Are you implying that the defective oil tube is in some way connected with the spline and other ADs.
I cannot for the life of me work out what you are saying. Perhaps it's a European thing. Would it be possible to do a translation for those of us in the Old World?
Back in 2003 there is an AD in which RR suggests that failure of spline lubrication can result in uncontained engine failure, in certain models of the RB 211 3-shaft style engine. RR identified the problem as excessive spline wear due to difficulties with the designed oil-air mist lubrication system for the splines.
RR did not say what might cause these difficulties to the oil-air mist, but it doesn't seem over-reaching to assume that problems with the oil tubing might result in too little oil in the mist.
I believe RR has said that spline failure might cause overspeed of the associated turbine stage, although they don't always say this explicitly. Here we seem to generally assume this would be due to loss of the load from the compressor driven by the particular stage.
Bearfoil has also described the oil-fire senario. We are all hampered by not having any good drawing details of this engine. But at least in that we are in good company-- Boeing had never seen any PW engine drawings until the engine problem just prior to the 747 rollout, despite having specified PW engines for more than two decades.
I quoted the Old/New World translation problem just to mention we have the same problem in reverse-- I'm still trying to figure out what the "abutments" of the splines are, in hopes I could understand how they "axially" locate the turbine, without any drawings. I am assuming these are what we call the "flanks" of the splines, but then in what way would they locate the turbine and keep it from moving rearwards...
OE