Wuzak,
From Tactical Planning, 20 Nov 1943,
A P-51 with the -39 engine has a max range at 10,000 feet of 1,000 miles or an endurance of 4.5 hours, based on 180 gallons of fuel.
A P-51A with the -81 engine has a max range at 10,000 feet of 1,000 miles or an endurance of 5 hours based on 180 gallons of fuel.
The same plane with 2x75 gallon drop tanks has a max range at 10,000 feet of 1,550 miles or an endurance of 7.6 hours based on 330 gallons of fuel.
The range number makes allowance for warm-up, test, taxi, take-off and landing. Also includes fuel consumed in climb with distance covered and time for climb included in the range and endurance numbers. Finally, 10% of net ideal range is allowed for differences in aircraft, pilot technique, equipment, and atmospheric conditions.
However, no allowances are made for wind, combat, formation flight or combat.
Eagledad