Originally Posted by
tdracer
Several years ago, we were investigating a particular Asian airline that had horrible time-on-wing for their 737/CFM56 engines. Mainly sort haul, they were running out of EGT margin in ~3,000 hours - at a time when the typical operator was in the range of 15,000-20,000 hour time on wing.
Come to find out, they were using max TO every single takeoff - never a derate of any kind. At around a million dollars to overhaul an engine, you'd have to save a whole lot of of fuel to justify an extra two million dollars/year in engine maintenance...
Treble that cost. Depends also on hour to cycle ratio and operating environment, which being in Asia can be vastly lower than a benign environment. A ME3 engine for example, could operate for probably half the time as Euro-loco, which should go to the LLP limiter at 20K cycles (if operated at ~1.5 FH : 1 FC).