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The F4U-4 with -18W engine was managing some 445 mph at 25000 ft - that would be hot airplane in anyone's book?
Some 10 mph faster than 1944 P-47Ds, and some 15 mph slower than P-47M/N. The M and N will be notably faster at 30 kft and above, maybe 50 mph plus. At SL the Corsair is some 10 mph faster than M/N, and some 40 mph than late P-47Ds.
The P-47M should climb a tad faster, the D and N slower than F4U-4.
However, these F4U-4 speeds were obtained using combat power with water injection - which was limited to about 5 mins total, and after that the engine would self destruct (literally) if not throttled back.
The use of water injection is quite deceiving since, for example, if it is used to boost climb rates to 20,000ft it is gone, and is not available for subsequent combat.
The use of WEP on a Merlin had no absolute time limit and the engine could be run continuously at the WEP rating until fuel exhaustion or the engine eventually fails, but on engines like the 2800-18W, which used water injection during combat (WEP) power, there was an absolute limit determined by the water capacity of the aircraft. If the engine was run at the WEP rating for even a few seconds after the water supply was exhausted the engine would self destruct and probably destroy the aircraft as well (see Guyton for details).Not sure what you're aiming at - no US engine in ww2 was allowed for more than 5 minutes at WER, be it with or without ADI. The often quoted ~440 mph figures for the Merlin Mustang were also obtained with engine running at WER, ie. 5 min rating.
Do we know how many minutes the ADI liquid lasted in US fighters, once engaged? How many fighters were climbing from SL to 20000 ft while using WER?
There is nothing deceiving in ADI system, extra power was always useful for pilots. The Spitfire V with ADI would not have any problems to beat the Fw-190 under 20000 ft.
The use of WEP on a Merlin had no absolute time limit and the engine could be run continuously at the WEP rating until fuel exhaustion or the engine eventually fails, but on engines like the 2800-18W, which used water injection during combat (WEP) power, there was an absolute limit determined by the water capacity of the aircraft. If the engine was run at the WEP rating for even a few seconds after the water supply was exhausted the engine would self destruct and probably destroy the aircraft as well (see Guyton for details).
The -4 had a 13.5 gallon water tank versus 10 gallons on the -1 (with WI). Max time was about 5mins before water exhaustion.
However, these F4U-4 speeds were obtained using combat power with water injection - which was limited to about 5 mins total, and after that the engine would self destruct (literally) if not throttled back. The use of water injection is quite deceiving since, for example, if it is used to boost climb rates to 20,000ft it is gone, and is not available for subsequent combat.
The use of WEP on a Merlin had no absolute time limit and the engine could be run continuously at the WEP rating until fuel exhaustion or the engine eventually fails, but on engines like the 2800-18W, which used water injection during combat (WEP) power, there was an absolute limit determined by the water capacity of the aircraft. If the engine was run at the WEP rating for even a few seconds after the water supply was exhausted the engine would self destruct and probably destroy the aircraft as well (see Guyton for details).
The -4 had a 13.5 gallon water tank versus 10 gallons on the -1 (with WI). Max time was about 5mins before water exhaustion.
Where did you get this from?
In order to GET a WER rating a test engine had to survive 7 1/2 hours at the WER rating. Granted it is 5 minutes at a time. Run 5 min at WER and then a 5 or more minutes at cruise or idle to lower temperature and then back to the WER setting.
The ADI was NOT a one shot deal. The F4U-1 carried just over 10 gals of ADI at roughly 7.5lb per gallon that is over 75lbs.
Flow rate for 2400hp was 9.2lbs per minute, or a bit over 8 minutes worth.
Flow rate for 1900hp in higher blower was 7.2lbs per minute. WER rating for the R-2800-8 was 1975hp at 20,000ft ( with RAM) or about 10 minutes worth. Granted it should be used 5 minutes at a time.
WER was for use in COMBAT only. Climbing to operational height should not use WER ( it shouldn't even use Military Power most of the time). Military power was not even allowed to be used for more than 5 minutes in the climb on the early planes.
The P-47 speeds are also using WER and ADI. The P-47 carried more ADI but would be subject to the same limitations.