Originally Posted by
MarkerInbound
As I recall 30 some years back we had a 2400 hour TBO. Maintenance could check the screens and do a valve lash and get a hundred hour extension. We could do that one more time and the engine finally had to come off at 2600 hours. We had several that made to the second extension.
Yes, impressive for big piston engine. I have found top civil Merlin TBO of between 650 and 800 hours in the early 1950's. Don't know the survival rate or average mortality for that TBO. Likewise, I wonder what failure profile R-2800 TBO figures were based on?
OAP