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WWII . How much water and additives did the plane carry when going into battle?

4 Answers


Well, I don't really know what I'm talking about, but at the end of this report, it says that water consumption was 2.1 gallons/minute in high-power flight.

See supplement  Water Injection on P-47D Airplanes, 3 February 1944   that can be found at the bottom of the test report at


About halfway down, it says that such planes carried 15 gallons of water in tests. I don't know if that was typical for combat missions.

"To report results of flight tests on P-47D-10 airplane, AAF No. 43-75035 run at the manufacturer's plant. Airplane equipped with Pratt & Whitney R-2800-63 engine with water injection; standard Curtiss 714-1C2-12 propeller; type A-17 turbo regulator. Airplane ballasted to simulate the following conditions: Six .50 caliber guns; 300 rounds per gun; 305 gallons gasoline; 15 gallons water; 14 pounds pyrotechnics. In this condition the gross weight was 13,234 pounds with a C.G. wheels up, of 29.63 percent M.A.C. Mixture auto-rich; throttle wide open on all tests. Horsepower data obtained with torquemeter."

I'm sure Rooster can clear this all up.


Dear Korvo,

I just want to say I really hope you receive a good answer for your question, but I cannot help...did not even realize that the P47-D was an airplane...

Korvo Virginia

well, its an old one (WW II), but I was reading about it, and never knew before that these engines were given additional cooling by injecting water into the Cylinders. Learn something every day.. LOL

Virginia Virginia

Korvo, you wait until Rooster Cogburn comes online, if anyone anywhere knows about this, he will! We have just been studying the synchronization of the WWI dogfighter airplanes, where the pilot also operated the machine gun so they figured out a way to synchronize the firing so you did not shoot off your own propellers...

Actually, sometimes Other Tink knows about airplanes, too; recently she found a video showing the WWI Fokker of the Red Baron, it had rotary cylinders...so I am glad to learn about fighter airplanes here!

Rooster Virginia

The P-47 started out as an escort fighter till the p-51 arrived in numbers and then was converted to a fighter bomber. I can't even list all the engines that use water injection.



Water injection was part of the turbo boost system. Many WW2 fighters used this system for extra power. Tink got the specs for you. Some race cars used this system also in it's time.

Superchargers and Turbochargers - Pacific Aviation Museum Pearl ...

Water Injection on P-47D Airplanes - WWII Aircraft Performance

The R-2800 is considered one of the premier radial piston engines ever designed and is notable for its widespread use in many important American aircraft during and after World War II. During the war years, Pratt & Whitney continued to develop new ideas to upgrade this already powerful workhorse, most notably water injection for takeoff in cargo and passenger planes and to give emergency power in combat.
Korvo Rooster

You would think that would be hard on the cylinders, with the sudden cooling effect on the inside, and the outer part being hot.  I would think the Inside would tend to contract and cause stress on the cylinders. Perhaps the cooling is not that great.

Korvo Rooster

Thought of something, Unless the cylinders had sleeves in them, then the sleeve would contract, giving a tighter fit around the piston, increasing the efficiency of the power stroke, thus more power. Sounds like it was a unique idea.  Thinking outside the box.

TheOtherTink Rooster

@ Korvo:

Yes, combat aircraft were (and are) very high-maintenance.

According to this article, WW2 fighter engines needed complete overhauls in as little as 50 hours of use, ranging up to maybe 500 hours, depending.


"The effect of this high supercharged power rating was lower engine life, with time between overhauls ranging from 50 to 500 hours."

Rooster Rooster

@Tink : Tell me about it! Big bucks to keep them maintained. The engine in my old BF-109G was a big V-12. Less maintenance but very costly when it was rebulid time.

TheOtherTink Rooster

@ Rooster,

Here's one that was built in 1950!

I didn't know they still made them after WW2.



You ought to ask Rooster for more specifications.

Here are some links (check the references):






T(h)ink provided already the links for water injection and performance.