I thought there was a difference in TBO? If yes, does it make a material difference reserve amounts?
Tim
Moderators: Rick, Lance Murray
I thought there was a difference in TBO? If yes, does it make a material difference reserve amounts?
Austro's are TBR at 1,800 now. The current cost is about $50K which will probably increase before most of us reach 1,800hrs.
The big difference *was* that DA62s need new heads at 900 hours, whereas DA42-VIs don't. While that applies to older DA62s, the newest DA62s have Austro "-500" model heads with the same TBR as the engine itself (1800 hours) and hence don't require head replacement. The disadvantage is that Austro seems to be having more issues (e.g., ADs related to production tolerances) with these new heads.
The issue was not with the tolerances of the new heads. It was a tolerance issue associated with the change in the location of one of the camshaft position sensors that coincided with the introduction of the new cylinder head. This required a change to the camshaft that has the toothed wheel that drives the high-pressure fuel pump (HPP). It was the tolerance of this part that created the HPP issue which has since been resolved. (I can hear the Lycoming owners snicker "yes, but what else hasn't been resolved, and are you sure it's really resolved?").
I agree that the new engine block wasn't the source of the problem; but there's more going on than just the drive gear to the high pressure fuel pump.