Originally Posted by
Feathers McGraw
It seems to me that Rolls-Royce may have made modifications under the usual policy of continuous development that most technology companies pursue.
That doesn't mean that they believed an in-service failure likely, it may well be that their previous information showed that the older engines would reach their overhauls without problems.
The change may also have been aimed at something else, but fix this issue as side effect.
Also, there
was the AD issued before the incident, which
may have been intended to cover this issue in the older engines. If it was, then maybe the AD wasn't sufficient or wasn't followed right, but RR could not be accused of doing nothing about a known problem.