Chaps, as a 'general' rule of thumb for medium to heavy jets, what's the most fuel efficient climb rate and criusing altitude please?
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Thanks, will check that out now!
The standard climb profile is to climb at 250ktias. Above 10,000' msl you can go to 270 or 280 kts depending on the what jet you are flying. Most jets fly anywhere from 31000' to 39000' ----- best true airspeed for mach no. The higher you go the more efficient the engines get. At high altitudes you will burn little more fuel per hour at cruise speed than than you will burn idling on the ground.