Speeds are with external loads
F6F-3, 250 gallons internal, 150 external, maximum speed 348 mph at 23,900 feet, combat radius 335 nautical miles.
F6F-5, 250 gallons internal, 150 external, maximum speed 355 mph at 23,900 feet, combat radius 340 nautical miles.
F7F-1, 426 gallons internal, 300 external, maximum speed 397 mph at 23,000 feet, combat radius 435 nautical miles.
F4U-1, 237 gallons internal, 175 external, maximum speed 387 mph at 24,600 feet, combat radius 340 nautical miles. However combat radius limited by amount of protected fuel for combat and return, 48 gallons remain in tank at combat radius and must be dropped or used to increase cruise out speed from 160 to 259 knots or for 64 minutes search at V for max range.
F4U-1D, 237 gallons internal, 300 external, maximum speed 353 mph at 24,200 feet, combat radius 335 nautical miles. However Combat radius limited by amount of protected fuel for combat and return, 145.7 gallons remain in tank at combat radius and must be dropped or used to increase cruise out speed to V max (286 knots) or for 2.32 hours search at V for max range
Class VF Airplanes. Practical combat radius is: 20 min, warm-up and idling (see notes 3 and 5 below), 1 min. take-off (see notes 4 and 5), 20 min. rendezvous at 60% normal sea-level power (N.S.P.) and auto lean (see notes 6, 7 and 8), climb to 15,000 feet at 60% N.S.P. and auto rich (see notes 6, 7, 8, 9 and 10), Cruise-out at 15,000 feet at V for max. range and auto lean, drop bombs and unprotected droppable tanks (see notes 13 and 14), 20 min. combat at 15,000 feet (see note 15), Descend, Cruise-back at 1,500 feet at 170 knots true air speed and auto lean (see notes 11 and 12), 60 min. at V for max. range and auto lean as allowance for rendezvous, landing and reserve, see notes 1, 2, 17 and 19.
1. Radius is given in nautical miles
2. In calculating radius, engine requirement fuel consumption data are increased 15% and flight test fuel consumption data are increased 5% at all power conditions of conventional engines For J.P. engines, use one half of the above percentage increases.
3. Warm-up:
a) Conventional Engines: 20 min, warm-up at 1/2 rated RPM on propeller load curve. Fuel consumed in pounds in 10 min. warm-up (including 15% increase) may be taken as 0.03 times sea level normal rated BHP of engines.
b) J.P. Engines: Equivalent to 30 sec. warm-up at maximum static thrust. Fuel consumed in pounds (including 7.5% increase) in warm-up and accelerating to maximum static thrust may be taken as 1.2% of the maximum static thrust rating of the J.P. engines at sea level.
c) Combination of Conventional and J.P Engines: Fuel consumed in warm up of all engines in accordance with (a) and (b) above, is considered in calculating radius unless it is specified that J.P. engines shall not be used for take-off in which case conventional engines only are warmed up.
4. Take off:
a) Conventional Engines: 1 min. take-off at rated take-off power.
b) J.P. Engines: 1 min. take-off at rated take-off thrust.
c) Combination of Conventional and J.P Engines: Conventional engines used at rated take-off power for 1 min. and J.P engines used at rated take-off thrust for 30 sec. All engines used for take-off unless it is specified that J.P. engines shall not be used.
5. Warm-up and take-off on internal protected fuel. Protected tanks may be refilled with fuel from unprotected tanks if fuel pump for this purpose is incorporated in the design. This will be noted on the sheet.
6. Rendezvous, climb and cruise out is on unprotected fuel if available.
7. For airplanes with combination of conventional and J.P. engines, the J.P. engines are not used in rendezvous, climb and cruise-out cruise-back and landing.
8. For airplanes with J.P engines only (no conventional engines)
a) 10 min. rendezvous at 60% normal rated thrust at sea level.
b) Climb to 15,000 feet is at maximum military rated thrust.
9. Auto. rich is used for climb unless flight test data are available indicating satisfactory engine cooling characteristics in climb with auto. lean.
10. If average rate of climb in climbing to 15,000 feet at 60% N.S.P. is less that 400 ft./min., climb is given at full normal rated power and auto rich.
11. Cruise-out or cruise-back speeds less than V for maximum range or greater than V at 60% N.S.P. are not used in calculating radius. Only a few of the older airplanes or new airplanes of special design are affected by this note.
12. For airplanes with J.P. engines only (no conventional engines), cruise-out and cruise-back at speed for maximum range.
13. If it is necessary to drop fuel before entering combat, the following note will be added. "Combat radius limited by amount of protected fuel for use in combat and return. XXX gal. fuel remain in unprotected tanks when entering combat and must be dropped, used for approximately YYY hrs. search, or used to increase speed in cruising-out to approximately ZZZ knots."
14. Radar if specified for the airplane is carried the full distance out and back in all radius problems.
15. Combat at 15,000 feet - Class VF Airplanes
a) Conventional engines: Combat 20 min. of which 10 min. is at war emergency rated power and 10 min. is at military rated power. If war emergency rating is not available, combat 20 min. at military rated power.
b) J.P. Engines: Combat at 15 min. at military thrust rating at 15,000 feet and maximum airplane speed.
c) Combination of Conventional and J.P Engines: Combat 20 min. of which 10 min. is at war emergency rated power for conventional engines plus military rated thrust of J.P. and 10 min. is at military rated power of conventional engines plus idling J.P. engines. If war emergency rating is not available, use military rated power.
16. Combat at 1,500 feet - Class VB, VBT, VSB and VTB Airplanes
a) Conventional engines: Combat 15 min. of which 5 min. is at war emergency rated power and 10 min. is at normal rated power. If war emergency rating is not available, combat 5 min. at military rated power and 10 min. at normal rated power.
b) J.P. Engines: Combat at 10 min. at military rated thrust at 1,500 feet and maximum airplane speed.
c) Combination of Conventional and J.P Engines: Combat 15 min. of which 5 min. is at war emergency rated power of conventional engines plus military rated thrust of J.P. engines and 10 min. is at normal rated power of conventional engines plus idling J.P. engines. If war emergency rating is not available, use military rated power.
17. Radius includes distance covered in climb, but not descent or dive.
18. In listing the scouting radius and the search radius, the following note will be added. " Practical XXX radius is reduced YYY nautical miles for each minute of combat at 1,500 feet at war emergency rated power of conventional engines plus military rated thrust of J.P. engines." In the note, military rated power is used if war emergency power rating is not available and reference to J.P engines is deleted if they are not incorporated in the airplane.
19. The complete radius problem is stated on the sheets.