McDonnell FH Phantom - Design and Development

Design and Development

In early 1943, aviation officials at the United States Navy were impressed with McDonnell's audacious XP-67 Bat project. McDonnell was invited by the Navy to cooperate in the development of a shipboard jet fighter, using an engine from the turbojets under development by Westinghouse Electric Corporation. Three prototypes were ordered on 30 August 1943 and the designation XFD-1 was assigned. Under the 1922 United States Navy aircraft designation system, the letter "D" before the dash designated the aircraft's manufacturer. The Douglas Aircraft Company had previously been assigned this letter, but the USN elected to reassign it to McDonnell because Douglas had not provided any fighters for Navy service in years.

McDonnell engineers evaluated a number of engine combinations, varying from eight 9.5 in (24 cm) diameter engines down to two engines of 19 inch (48 cm) diameter. The final design used the two 19 in (48 cm) engines after it was found to be the lightest and simplest configuration. The engines were buried in the wing root to keep intake and exhaust ducts short, offering greater aerodynamic efficiency than underwing nacelles, and the engines were angled slightly outwards to protect the fuselage from the hot exhaust blast. Placement of the engines in the middle of the airframe allowed the cockpit with its bubble-style canopy to be placed ahead of the wing, granting the pilot excellent visibility in all directions. This engine location also freed up space under the nose, allowing designers to use tricycle gear, thereby elevating the engine exhaust path and reducing the risk that the hot blast would damage the aircraft carrier deck. The construction methods and aerodynamic design of the Phantom were fairly conventional for the time; the aircraft had unswept wings, a conventional empennage, and an aluminum monocoque structure with flush riveted aluminum skin. Folding wings were used to reduce the width of the aircraft in storage configuration. Provisions for four .50-caliber (12.7 mm) machine guns were made in the nose, while racks for eight 5 in (127 mm) High Velocity Aircraft Rockets could be fitted under the wings, although these were seldom used in service. Adapting a jet to carrier use was a much greater challenge than producing a land based fighter because of slower landing and takeoff speeds required on a small carrier deck. The Phantom used split flaps on both the folding and fixed wing sections to enhance low-speed landing performance, but no other high-lift devices were used. Provisions were also made for Rocket Assisted Take Off (RATO) bottles to improve takeoff performance.

When the first XFD-1, serial number 48235, was completed in January 1945, only one Westinghouse 19XB-2B engine was available for installation. Ground runs and taxi test were conducted with the single engine, and such was the confidence in the aircraft that the first flight on 26 January 1945 was made with only the one turbojet engine. During flight tests, the Phantom became the first naval aircraft to exceed 500 mph (434 kn, 805 kph). With successful completion of tests, a production contract was awarded on 7 March 1945 for 100 FD-1 aircraft. With the end of the war, the Phantom production contract was reduced to 30 aircraft, but was soon increased back to 60.

The first prototype was lost in a fatal crash on 1 November 1945, but the second and final Phantom prototype (serial number 48236) was completed early the next year and became the first purely jet-powered aircraft to operate from an American aircraft carrier, completing four successful takeoffs and landings on 21 July 1946, from USS Franklin D. Roosevelt near Norfolk, Virginia. At the time, she was the largest carrier serving with the U.S. Navy, allowing the aircraft to take off without assistance from a catapult. The second prototype crashed on 26 August 1946.

Production Phantoms incorporated a number of design improvements. These included provisions for a flush-fitting centerline drop tank, an improved gun-sight, and the addition of speed brakes. Production models used Westinghouse J30-WE-20 engines with 1,600 lbf (7.1 kN) of thrust per engine. The top of the vertical tail had a more square shape than the rounder tail used on the prototypes, and a smaller rudder was used to resolve problems with control surface clearance discovered during test flights. The horizontal tail surfaces were shortened slightly, while the fuselage was stretched by 19 in (48 cm). The amount of framing in the windshield was reduced to enhance pilot visibility.

Halfway through the production run, the Navy re-assigned the designation letter "D" back to Douglas, with the Phantom being redesignated FH-1. Including the two prototypes, a total of 62 Phantoms were finally produced, with the last FH-1 rolling off the assembly line in May 1948.

Realizing that the production of more powerful jet engines was imminent, McDonnell engineers proposed a more powerful variant of the Phantom while the original aircraft was still under development — a proposal that would lead to the design of the Phantom's replacement, the F2H Banshee. Although the new aircraft was originally envisioned as a modified Phantom, the need for heavier armament, greater internal fuel capacity, and other improvements eventually led to a substantially heavier and bulkier aircraft that shared few parts with its agile predecessor. Despite this, the two aircraft were similar enough that McDonnell was able to complete its first F2H-1 in August 1948, a mere three months after the last FH-1 had rolled off the assembly line.