EdSet100; You could be right. It is just that photographs that I have of XV227, immediately after the incident, do not show any material "cladding" around the pipe.
Also, with reference to Mr Points comments, the XV227 recommendations ask for a maintenance and lifing policy for the damaged and similar ducts. Whilst we can all agree that it is most unlikely that the damaged duct will fail again during the life of the Nimrod, we should be concerned about the others. Lets face it, if a section of your car exhaust fails due to aging, then there it a good chance that other sections are in a similar condition. That is why BAE were asked to carry out a survey back in 2005, which is still outstanding.
DV