A partial answer only:
- The Flight crew training manual (FCTM) says in chapt 4.1 that FF during holding with flap 1 is aproximately 10% more than with flap up
- the Flight planning & performance manual (FPPM) says in the intro of the chapter 2 that during descent each additional minute of flap down consumes about 75 kg of additional fuel (gear retracted!)
I know different company or pilot's notes state that the fuel burn with LE extended is increased by about 10% but I can not find it back in my boeing official docs.
Pls keep me advised if you get more
regards
