The XP-67 was the first attempt by the McDonnell corporation to build a fighter for the United States Military. The same corporation would go on to built the superb F-4 Phantom II, F-15 Eagle and F-18 Hornet air superiority and strike fighters would initially see some bumps in the road, led by none other than James S. McDonnell himself.
McDonnell had acquired a substantial amount of aeronautics education in his schooling (Princeton), having served with the Army Air Service and ultimately various aircraft manufacturers. With one successful design under his belt (stalled by the arrival of The Great Depression), McDonnell sought to earn his own wings under his own banner. Thusly, the McDonnell company was born and looked to make some quick connections with the US Military.
The XP-67 was such a connection. A very ambitious design in every sense of the word, the fighter was intended to be the Allied answer to killing enemy bombers in the sky. The formidable aircraft would undertake a radial design that saw the entire aircraft visually flattened from end to end. The twin engine system would have its engines forged straight into the large wing area generating a stable about of air flow, drag and lift. The single-seat cockpit was planned to be pressurized and the aircraft was designed to reach top speeds close to 500 miles per hour. Alas, the final product would not come close to matching those specifications - a project too ambitious for the time.
Armament of the XP-67 initially consisted of a 6 x 12.7mm machine gun array with an additional 4 x 20mm cannon. This was later upgraded to a 6 x 37mm cannon system with speculative designs also featuring a single massive 1 x 75mm cannon. In any respect, the XP-67 would have been the consummate bomber-killer that McDonnell and the US Military had envisioned from the beginning. Unfortunately, the intended armaments were never added to the prototype system itself.
With the first prototype rolling out in December of 1943, it quickly became apparent that the engines would be prone to catching fire. With the engines held deep in the nacelles, the fire would have already begun to spread uncontrollably before being noticed, adding an unacceptable element of danger to the design. Cooling of the engine also became an issue throughout testing and the turbo chargers never lived up to expectations.
By 1944, with Germany's air force concentrating mostly on its fighter designs, the need for a true dedicated bomber-killer was no longer. As a result, the Army saw fit to cancel the XP-67 project. A second XP-67 - this one with a jet powerplant in the rear along with the two propeller engines - was almost complete when the cancellation call came in.
With the effective death of the XP-67 and lessons learned, the McDonnell corporation would turn its attention to the arrival of the jet age and begin a production run of very successful aircraft. Had the XP-67 been allowed to fly, had its engine issues ironed out and had Germany still maintained a bomber force to be reckoned with, the XP-67 would have quite possibly been the Allied answer to combat the Reich in this fashion.
Dimensions:
Length: 44.78ft (13.65m)
Width: 54.99ft (16.76m)
Height: 15.81ft (4.82m)
Performance: (About MACH)
Maximum Speed: 270mph (434kmh; 234kts)
Maximum Range: 2,384miles (3,836km)
Rate-of-Climb: 2,600ft/min (792m/min)
Service Ceiling: 37,999ft (11,582m; 7.2miles)
Structure:
Accommodation: 1
Hardpoints: 0
Empty Weight:17,749lbs (8,051kg)
Maximum Take-Off Weight:25,399lbs (11,521kg)
Powerplant:
Engine(s): 2 x Continental XIV-1430-17/19 radial engines generating 1,600hp each.
Armament Suite:
Original:
6 x 12.7mm machine guns
4 x 20mm cannons
Updated Design:
6 x 37mm cannons
Planned:
1 x 75mm cannon
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