RB 211 POWERPLANT DETERIORATION - REVIEW OF CURRENT SITUATION AND LESSONS LEARNED 811053
The basic causes of in-service engine performance deterioration are summarized and the features of the RB 211 which have been designed to minimise deterioration are described. These features ensure that installation performance loss is virtually non-measurable.
Areas where deterioration occurred on the first of the RB 211 variants, the -22B, are described together with the modifications which were incorporated in the -524, the second in the RB 211 family, to overcome these problems. In service airline results show the improvement in deterioration levels as a result of these modifications.
An assessment of the problem areas on the -524 has led to further modifcations being incorporated the -535, the third engine in the RB 211 family. Initial test bed deterioration levels of the -535 are very low.