Bob Blease could tell the story better, but I seem to remember him telling me he went to a meeting in Bath over engine spares for the TUT's and the MEO for Ocean was there with the same problem. That was the lead in time for spare heads etc. Because the German owners/engine builders did not keep spares and the lead in period for new heads etc was many weeks, which caused headaches for maintenance and repairs, plus the MoD stopped keeping B type spares because of storage costs and sent a lot of stores for scrap because a private business man brought in to help lower costs recommended these measures, dare say Bob will give a more inform view on this.