A B747-400 standard taxi allowance is 1,000kg and the allowed usage rate is 70 kg/min. We used over 2000kgs on taxi at JFK earlier this evening but the place was clogged up with approx thirty other a/c taxiing in front of us. It took 1:15 from pushback to airborne, and that was reasonably short! Average flow rate in cruise is 1,000kg every 5 minutes or 12,000kg/hr, a lot higher when heavy, around 15,000kg/hr down to about 9,000kg/hr just before descent. Total descent burn, if not d!cked around by wx or the air traffic situation, less than 1,000kg. Takeoff usage rate max thrust no derate around 8,000kgs/hr per engine.
See ya!
