A320 flex choice
 

Hi everybody, when you calculate the flex temp using LPC do you choose the highest temperature or you choose a lower temp that gives you more margin than the highest flex?

Highest temperature (whatever the LPC gives you - only one temp is given...)

there is only one temp given, and it gives quite a bit of pad. If you need more just go max.

i think highest flex temperature, is the better option mostly, and optimun flaps is always or almost always flaps 3, but some time using flaps 2 is giving you same flex temperature but better V2 (higher) so shorter 3rd segment. Company ops manual should give you this politics use of flex temp, if not highest is the best.

Based on what? Engines savings or performance?

You bet, fuel and engine maintenance, due to spread of hot point check. NOT perfomance, but you have always MAX thrust available TOGA

So you have statistical analysis of the savings associated with deep derates?

"The first degrees of flexible thrust have an impact on maintenance costs about 5 times higher than the last one" from FCTM