Bell P-63A RAF trials 1945

Ad: This forum contains affiliate links to products on Amazon and eBay. More information in Terms and rules

OldGeezer

Airman 1st Class
207
422
Dec 11, 2020
Interesting, in the background of the top photo is one of the two P-63As that the Brits took for testing. Wonder what ever became of that?

1675527033642.png
 
Going to the french i think.
Two delivered to Britain: FR408, ex 42-68937, delivered Speke to RAE Farnborough on May 17, 1944. Crashed there July 31 when gear failed to lower after 5:15 flyng hours. Replaced by FZ440, ex 42-69423, delivered Renfrew to Farnboriugh on September 20, 1944. Used for laminar flow wing trials until 1948 and sold for scrap in 1949.

Source: Air Arsenal North America by Phil Butler

Bit more detail: Both aircraft were used for laminar flow trials. FR408 was camouflaged in standard RAF fighter scheme. Before disposal, wings from FR440 were removed and used for wind tunnel trials.

Source: Lend-Lease Aircraft in World War II, Arthur Pearcy

Robert
 
Last edited:
Too bad they did not try to adapt the P-63 wing to the P-59, with 138 less sqft and some laminar flow, the P-59 may have achieved airspeed closer to desire level.
 
The real problem with the P-59 was the pitiful top speed, 413 mph, compared to the Me 262, 560 mph, with the same thrust rating. the P-59 wing was about 60% more area than the Me 262, The P-63 wing was approximately equal to the Me 262. For those who like solving mathematical problems they could probably calculate the P-59 max speed with the P-63 wing.
 
Last edited:
The P-59 had about the same climb rate as the P-51D. If you cut down the wing then you'd have an aircraft with a RoC inferior to the piston aircraft already in service. The Germans and British both studied single engine jets for their first gen jet aircraft but decided on twins in large part because of climb rate needs. It was only towards the end of the war, with the Hes 011, J33 and Goblin that single engine jets with better RoC than pistons became possible.
 
Big wings do not give high rate of climb.
This is a fallacy.

If you clip wings you can improve the rate of climb.
Climb is pretty much governed by the power to weight you have after you deduct the power needed to fly at climbing speed.
Slap a big wing on an aircraft and you increase the drag which means you have less power to use for climb after you get the plane u to 160-180mph or whatever the best speed for climb is.
Jets have sort of a double whammy because jets don't make a lot of power at low speeds. Bad phrasing, their power doesn't work efficiently at low speed. Kind of a like a prop stuck in the wrong pitch.
Jets were also heavy, they were carrying a crap load of fuel.
P-59A went about 10,900lbs clean and held 290 US gallons of fuel internal.
P-63 went about 8,800lbs clean and held 126 US gallons of fuel internal.

They may have wanted the big wing for better take-off and landing.
Or they may have wanted it for fuel storage, or both.
290 gallons was good for about 240 miles of range at 20,000ft. A pair of 150 US gal drop tanks got you up to 520 miles.

Remember that the engine power was changing about every other time the airframe designers turned around.
April 1942 has 1250lb thrust, then 1400lb, then 1600lbs and the engines used in the YP-59s were supposed to give 1650lbs. The engines in the first 3 prototypes gave closer to 1300lbs as installed.

Some P-59Bs got 2000lb thrust engines after sitting in storage for a while so make sure you are comparing the right aircraft/engine combo.

Thrust is not power. Jet plane running at full throttle with brakes locked and wheels chocked is make no "power". Power needs a time element.
One horsepower is a unit of power equal to 550 foot-pounds per second.
Without the time element you have a force like torque.

A jet engine can gain "power" as the static thrust declines because the engine/aircraft is moving faster.
An early version of the engines used in the McDonnell FH-1 Phantom were rated at 1400lbs static at sea level.
However the engines were rated at 525lbs thrust at 500mph at 30,000ft.
Which was enough to get this
FH-1s_NAN11-49.jpg

to do about 500mph at 30,000ft.
But we are dealing with different formulas. You need to know the veleocity of the exhaust gas leaving the jet engines (through the nozzles) and the mass and compare that to the speed of the aircraft.
 
Excess thrust is what determines the rate of climb, and generally the greatest excess thrust will be available near best L/D. If you cut the wingspan down then you are increasing the spanloading, which means the induced drag shoots up. Since best L/D occurs where parasitic=induced drag, then you have reduced the best L/D ratio, or in other words you have increased the minimum drag. Thus the amount of excess thrust available will drop which lowers RoC.
 

Users who are viewing this thread

Back