Engine selection in commercial aviation is IMO still largely motivated by politics - be it on a company ot national scale. My company is one of the few operators that fly both the CFM and the IAE engine - for the forementioned reason.
My personal summary: The IAE takes longer to start (CFM ~ 2x30", IAE ~ 2x60"), needs longer warmup and cooldown times, is harder to regulate (required changes in TLAs are too small in the approach power regime - we usually fly without A/THR for final approach & landing), the EPR-powersetting (1.0xx EPR) is harder to read than a normal N1-gauge (especially in turbulence and/or on the ships with CRT-displays) and the overall failure rate is higher in our fleet compared to the CFMs.
So I'd prefer the CFM right away.
Best Regards, MAX reverse
Last edited by Mäx Reverse; 25th Aug 2010 at 08:19.