Look up in Google: "derated climb performance in large civil aircraft" , and you get the whole story. Interesting.

@skyjob, we do not fly to the UK, but pretty much everywhere else in europe and get unrestricted climb in the majority of all cases.

Granted, if a low level off altitude is expected we do use reduced climb power.

Derated Climb Performance In Large Civil Aircraft
 

Here, try this....

http://www.theairlinepilots.com/foru...erformance.pdf

TO2 with full derate is only about 60% of max thrust.

777-300, at idle, is 737 cruise power. Similar fuel flows - 2700 lbs/hr +/-.

2700 per engine?! Surely you're joking. Right? That's insanely high. What's the fuel flow during takeoff and at cruise?

fuel capacity for 777-300ER from wikipedia: 320,863 lb / 145,538 kg

so let's say limit is 16h in the air that's 20053lbs/h or 9096kg/h
per engine that would be around 10026lbs/h or 4538kg/h.

now that's probably a bit high because it can stay in the air longer, not sure.
doing the same rough calculation for 7h of endurance of an 737-800 the 3000lbs/h seems realistic.

the 777 idle i would guess he is talking flight idle not ground idle.
but a much more pertinent question: why is this discussion in this thread?

Rick777: One other important concept with using derate is that min control speeds are based on the derate...
Note: V1 is based on the derate, not VMCG. V1 for TASS is based on full thrust TO, therefore in case of engine failure after V1 during TO with TASS you may increase power to MAX, but you may not perform this action during TO with D1 or D2 thrust setting, otherwise you will live RW a lit at bit early and in unpredictable direction.