- Yes
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Hello everybody. I’d like to suggest the Lockheed XF-90A for US aviation in War Thunder. The Lockheed XF-90A was a prototype escort and penetration fighter built in response to the United States Air Force requirement in 1945. It was the first USAF swept-wing fighter jet to be equipped with afterburners. Due to woefully underpowered Westinghouse J34 powerplants, the XF-90A lost to the McDonnell XF-88A Voodoo in the competition and never entered production.
Key Characteristics
- Long-Range Jet Fighter
- Sturdy airframe with swept wings and wingtip fuel tanks, inheriting some traits from the F-80A design
- Two Westinghouse J34-WE-15 axial-flow turbojet engines with an afterburning capability
- 6 x 20-mm cannons (not installed in the prototype but planned)
History
On August 28, 1945, the United States Army Air Forces (later separated as the United Air Forces) announced a new requirement for a twin-engine penetration fighter with swept wings capable of escorting jet-power bombers over enemy territory and back. It was required to have a combat radius of at least 900 miles.
By this time, World War II was over in Europe and the Pacific. The air doctrine was reshaped and advocated that the large formations of bombers, escorted by long-range fighters, would cause mass destruction on enemy targets below. The fighter escort was essential for the survival of bombers in enemy airspace. With the Soviet Union being the chief Cold War contender, it was undoubtedly attempting to outpace the West with its numerous jet-powered fighters and bombers.
The requirement sought a new fighter that fulfills the long-range penetration fighter and bomber escort roles. Although both terms had similar concepts, they differed in tactical movements. The penetration fighter’s role would not operate in close formation with bombers. Instead, it would penetrate deeper enemy airspace and neutralize any threats ahead of the bombers. These fighters could return to the bombers and continue the escort duty after the incursion. The North American P-51 Mustangs had demonstrated this part of the air doctrine during the turning points of the air war in World War II. In the post-war period, the development of jet-powered strategic bombers made propeller-driven fighters and earlier non-afterburning jet fighters difficult to keep up. Hence, this requirement was created in the first place to bring more modern aircraft designs powered by the after-burning jet engines.
Competitors for the contract included MCDonnell’s XF-88A, North America’s YF-93, and Lockheed’s XF-90. Lockheed received a contract to construct two prototype XF-90s on June 20, 1946.
In 1947, the XF-90 had originally been a delta-winged design, but wind tunnel tests indicated that such a configuration would not be viable. It was later redesigned with 35-degree sweptback wings, a sharply-pointed nose, and two Westinghouse J34-WE-11 axial-flow turbojet engines mounted side-by-side in the rear fuselage and fed by side-mounted air intakes. The wings were featured with the leading-edge slats, Fowler flaps, and ailerons on the trailing edge. The cockpit was pressurized and fitted with an ejector seat and a bubble canopy. The internal fuel could be supplemented by wingtip-mounted tanks, totaling a capacity of 1,665 US gallons. One of the most innovative features of the XF-90 design was its variable incidence vertical tail fin, which could be adjusted to move forward or back to assist in adjusting the horizontal stabilizers. The aircraft was designed to be fitted with six 20-mm cannons horizontally below the engine intakes, with three guns to each intake. It was also capable of carrying two 1,000-lb bombs and eight 5-inch rockets.
Consequently, the early changes to the XF-90 designs forced a delayed first flight. The initial prototype (46-687) was finally ready for flight testing in the spring of 1949. The prototype was fitted with non-afterburning J-34-WE-11 turbojet engines. It was found out it lacked the necessary power for take-off, so it was fitted with Rocket-Assisted Take-Off canisters for support. The prototype made its maiden flight on June 3, 1949, out of Edwards Air Force Base. Although the test flight was completed without problems, the performance was disappointing because of its excess weight and the power of its non-afterburning J-34 engines.
Seeking more power, Lockheed built the second prototype (46-688) with afterburning J34 turbo jets. These engines were also retrofitted to the initial prototype. The second prototype, redesignated XF-90A, completed its first flight on April 12, 1950. It had achieved a maximum speed of 668 mph in level flight at sea level and reached a maximum speed of Mach 1.12 in a dive. It went on to exceed the sound barrier several times without any structural problems. The XF-90A had almost cost the life of an experienced test pilot when it had great difficulty in pulling out of a dive.
Although the improved performance was better than most early fighter jets, it was still insufficient to be considered acceptable to the USAF. The fly-off between the Lockheed XF-90A, the McDonnell XF-88A, and the North American YF-93A occurred between June 30, 1950, and July 8, 1950, for the final evaluation by the USAF officials. On August 15, 1950, the Evaluation Board declared the McDonnell XF-88A the winner. McDonnell secured the production contract in September 1950, but the penetration fighter project was later canceled and abandoned due to the changes in Air Force priorities, along with a budget deficit.
The inadequate performance of the XF-90A was mainly attributed to the excessive weight and underpowered powerplants. The XF-90As were built with 75ST aluminum rather than the then-standard 24ST aluminum alloy, along with heavy forgings and machined parts. These materials made the airframe very sturdy. However, these materials resulted in an aircraft with an empty weight more than 50% heavier than its competitors. The bottom line was the issue with this overall aircraft design, which was described as “overbuilt and underpowered.”
After losing the production contract, the two remaining XF-90As were subjected to additional testing. The first XF-90A (46-687) was shipped to the NACA Laboratory in Cleveland, Ohio in 1953 for structural tests. It was no longer flyable, and its sturdy airframe was tested to destruction. The other XF-90A (46-688) had survived three atomic blasts at Frenchman Flat within the Nevada Test Site in 1952. In 2003, the XF-90A (46-688) was recovered from the Nevada Test Site; it was decontaminated and restored as the museum aircraft on display at the National Museum of the United States Air Force in Dayton, Ohio.
Specifications
Lockheed XF-90AGeneral Characteristics
- Crew: 1 (Pilot)
- Length: 56 ft 2 in (17.12 m)
- Height: 15 ft 9 in (4.78 m)
- Span: 40 ft (12.20 m)
- Wing area: 345 sq ft (28.4 sq m)
- Powerplant: 2 x Westinghouse J34-WE-15 afterburning axial-flow turbojet engines
→ 8,400 lbf (37.4 kN) thrust A/B
→ 6,000 lbf (26.7 kN) thrust dry- Internal Fuel: 1,665 US gal. (6302 L)
- Empty weight: 18,050 lb (8,204 kg)
- Gross weight: 27,200 lb (12,363 kg)
- Max. Takeoff Weight: 31,060 lb (14,118 kg)
Performance
- Thrust-Weight Ratio: 0.30
- Sea Level Speed: 668 mph (1,075 km/h)
- Wing Loading: 79 lb/sq ft (386 kg/sq m)
- Rate of Climb: 5,555 fpm (28.2 m/s)
- Time of Climb: 4.5 minutes to 25,000 ft (7,620 m)
- Service Ceiling: 39,000 ft (11,890 m)
- Range: 2,300 miles (3,680 km)
Armament
- Guns:
- 6 x 20-mm M24 cannons (unknown # of rounds)
- Bombs:
- 2 x 1000-lb bombs
- Rockets:
- 8 x 5-inch (127-mm) HVARs
- Others:
- RATO Canisters
Diagrams
Cockpit
Images
Conclusion | Why it should be in the game
The XF-90A was the first USAF jet with an afterburner and the first Lockheed jet to fly supersonic, only in a dive. Along with other innovative features, its underpowered performance did not win the contest. However, I feel it should be added as the earliest jet fighter with an afterburning capability for US aviation in War Thunder. It would serve as a transitional aircraft between the F-80 Shooting Star and the F-104 Starfighter. Its subpar acceleration and excessive weight, combined with the sturdy airframe to withstand some substantial damage, would make it a decent energy fighter and support fighter at best in the game.
See Also
I made a suggestion of the North American YF-93A Sabre, the XF-90A’s competitor. If you’re interested in this suggestion, check this out!
- Lockheed XF-90 – Let Let Let – Warplanes
- Lockheed XF-90
- Lockheed XF-90
- Lockheed XP-90 / XF-90 Prototype Escort / Penetration Fighter Aircraft
- Lockheed XF-90 - Wikipedia
Thank you for taking the time to read my suggestion! 😃
