Was just about to ask a similar question, but I found this thread and it seems relevant so I'll ask it in here.
Am I right in thinking the RR
Trent 600, 800 and 900 series have cascade thrust reversers? And if so, why does the 700 series, as in use on the A330, have the four-door petal "pop-up" type described above? Is there a fundamental design difference in the engine that requires this? Or is more to do with the shaping of the engine cowling due to aerodynamic requirements, that is the main reason?
It is indeed the CFM56-5 series in use on the A320 and A340 family that has that type of reverser. Regarding it being a special request by airlines - that is not the case. If the airlines order CFM engines, then that is the kind of reverser they come with, unlike the IAE which has the cascade type. The CFM56-3 and 56-7 on the 737, however, also have the cascade type. (As for the first part of your question, I'm unable to answer that I'm afraid, but I'm sure there's someone who can!)
[Edited 2004-05-25 19:12:37]
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