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Old 2nd Nov 2008, 21:48
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gibas
 
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Fkex T/O limited to Max Climb

Thanks again John Tullamarine!

Wal Stack's legacy from the golden sixties still applies.
Tflex thrust cannot be lower than the Max Climb Thrust (EPR) at the same flight conditions.
That's written on the Introduction of my A320 RTOW (IAE V2500) and as the max 25% reduction, the FADEC takes both limitations into account to determine Flex EPR. That's based on JAR/FAR.

Another amazing line in this intro is that: The Flex T/O thrust cannot be lower than the Max Continuous Thrust used for the final T/O flight path computation (at ISA+40)

Now for those reluctant guys for the MCT/CLB affaire, I wonder where is located the MCT/FLEX detent on the Airbus lever?
Last time I looked at it it was beyond the CLB detent, so according to the more beyond the greater the thrust (basic) rule, it should be clear that FLEX thrust is always greater than CLB if you respect the limitations.
The peculiar detent system on the Airbus levers is such thet MCT detent coincides with FLEX detent, which can be misinterpreted.
Think on what happens in your last sim after cleaning up after and ENG FAIL and climbing at green dot. You get out from FLEX to MCT by advancing or retarding your lever from FLEX and back again to the same detent to get MCT, but if you take a look at your EPR or N1, or if you listen carefully you'll notice a power/thrust reduction.

Thanks.
gibas is offline