XP-54 "Swoose Goose"
The Vultee XP-54, or the "Swoose Goose" as it was nicknamed,
was a prototype high-altitude interceptor aircraft developed by Vultee
to fulfill a U.S. Army Air Corps request for a combat aircraft with
an unusual configuration.
Vultee's XP-54 was one of three designs submitted to the competition
early in 1941 - the other two aircraft being the Curtiss-Wright
XP-55 Ascender and the Northrop
XP-56 Black Bullet. But it was the XP-54 which impressed the air
force the most, leading to a contract for two prototypes.
Initially the brief had called for a low level interceptor, but by
September of 1941 this had changed to to a high altitude interceptor
request. This crucial change meant the XP-54 had to be modified, a
turbocharger was added to the engine, more armor was fitted and the
aircraft received a pressurized cockpit. These alterations drastically
increased the weight, taking it from 11,500 lbs (5,200 kgs) to 18,000
lbs (8,200 kgs).
Aside from the unconventional twin boom tail and pusher propeller
arrangement, the Vultee XP-54 was also unusual in a number of other
ways. Firstly, the nose could be moved up and down (3 degrees up and
6 degrees down). The nose also housed all the aircraft's armaments,
which consisted of two 37mm cannons and two .50 cal machine guns.
The machine guns were mounted on movable mounts and were controlled
by a special compensating gun sight.
The other bizarre feature of the XP-54 was the cockpit entry system.
Because of the pressurized cockpit requirement, the engineers decided
it would be simpler to have the pilot enter the aircraft from the
underside. They came up with the idea of the pilots seat acting as
an electrically powered elevator to lift them up into the cockpit.
Due to this system the bailout procedure was equally topsy-turvy,
with the pilot having to be lowered out the bottom before being tipped
out of the seat at a distance great enough to clear the whirling blades
of the propeller just behind.
Flight testing of the first prototype began in January of 1943. The
initial results were rather disappointing, the aircraft was underpowered
- the first choice for the engine (Pratt & Whitney X-1800) had
been discontinued and the replacement (a heavier Lycoming XH-2470
) was inadequate. To make matters worse the XH-2470 proved unreliable
and was discontinued shortly after, leading to more costly delays
and potential modifications to accommodate yet another powerplant.
In the end the military decided to cancel the program and instead
concentrate their efforts on more conventional aircraft.
Sadly for the XP-54 and its designers, the aircraft itself wasn't
to blame. It featured some clever ideas and unusual concepts which
given time may have proven themselves. But the fiasco with discontinued
and unreliable engines meant it ran out of time before it could really
show what it was capable of.