Compressor Stall
I worked on the RB 199 , in the Design Office, at Filton with Rolls Royce Ltd.
Position: Senior Design Engineer & Section Leader. I worked under Trevor Laseter, our Group Leader.
It was not uncommon for new aircraft to suffer from Compressor Stall. This rules out Bogus parts theory.
The only factor that I am aware of, is the rate of change of R.P.M. of the spool.
Once up-and-running, at constant R.P.M., a compressor will never stall.
The Engine computer will control rate-of-change of RPM, within prescribed limits.
It is a sticky subject which can only be solved with an Ejector seat, on the Tornado.
However, the end result is always the same. i.e. Brown underpants.