1950s Fighter-Bomber: 5 Fast Facts About The Republic F-84F Thunderstreak

1950s Fighter-Bomber: 5 Fast Facts About The Republic F-84F Thunderstreak

Decades ago, on June 3rd at Edwards Air Force Base in California, Republic Aviation test pilot Oscar O. “Bud” Haas would make the first flight of the XF-96A, a swept-wing variant of the F-84 Thunderjet. The year was 1950, and 22 days after the first flight of the new swept-wing Thunderjet, North Korea would send more than 98,000 men across the 38th parallel, overwhelming the defenses of South Korea and bringing the world back to war at the dawn of the new era of world conflict: the Cold War.

Technological development hadn’t slowed since the end of World War II, and with a modified fuselage and control systems built around a new larger engine, the XF-96A would become the F-84F Thunderstreak. The Thunderstreak became the first jet-powered fighter bomber in the United States Air Force. More than 3,000 examples of the type would be produced – rivaling the production of the Hawker Sea Fury and Douglas A-1 Skyraider. The aircraft quickly earned a reputation and was adopted by NATO allies like Belgium, Denmark, Norway, The Republic of China, and Turkey. Here are five facts about the iconic fighter bomber.

Based on the F-84 Thunderjet

First flown four years apart

Maiden Flight

Top Speed

F-84

February 1946

541 Knots

F-84F

June 1950

604 Knots

Saying that the F-84F was based on the F-84 Thunderjet is accurate; however, it withholds the details of the complexity and the politics. The F-84 itself was riddled with design faults that included both airframe and engine issues. While this would be expected of any early jet, the F-84’s reputation for engine problems originally meant deployment to Korea didn’t occur until December of 1950, when the aircraft was assigned to a bomber escort role.

The F-84 became a liability after the entrance of the MiG-15 into the war. Its first shootdown occurred in 1951 before the aircraft was relegated to a ground attack role, with the Air Force knowing that it was unmatched when fighting the more agile MiG. The more agile and faster F-86 Sabre was selected for its air-to-air combat role, and Republic knew it was the swept-wing design utilized by both the MiG-15 and F-86 that gave them an advantage.

The performance of the swept-wing design was noted when the F-86 first began testing and before its 1949 introduction to the Air Force. This swept wing forced Republic engineers to return to the drawing board to modify their jet and incorporate the new swept-wing technology.

Design for the swept-wing variant began shortly after the first flight of the F-86. By June 3rd, 1950, the engineers had done it, and their new swept-wing variant was 63 knots faster than the original F84.

Modified for British Engine

Eventually utilized the Wright J65-W-3

Thrust

7,220 lb

Range

1,900 miles

Rate of Climb

8,200 ft/min

Sweeping the wings wasn’t the only design change; the redesigned aircraft also required a new engine. Its original General Electric J-35 was underpowered and performed poorly, causing the designers to swap out that jet for the Wright J65. The Wright J65 engine used on the F-84F was a known development of the British Armstrong Siddeley Sapphire engine, which had its first run in 1948.

Curtiss-Wright acquired the license for the jet engine and set out to build it in the United States. The new J65 engine had its first run in 1951, and the prototype jet would be modified to fit it. The modification required the elongation of the fuselage and the internal moving of systems to accommodate the larger jet.

Armament

With as many as 30 weapons, the F-84F packs a heavy punch

Featured:

• 6 x .50-caliber machine guns (up to 1,800 rounds)
• 24 x 5-in rockets (up to 6,000 lb total)

The 50-caliber machine guns allowed the aircraft to strafe targets up close and personal, with the rocket-competent adding additional force to the strafe.

The F-84 that the F-84F was developed from had a long legacy of serving in the ground attack role, and the F-84F filled the shoes and would go on to be modified to be equipped with a camera. Variants armed with cameras were aptly named RF-84F Thunderflashes.

Competed with World War II Aircraft

First introduced in 1954, but began being phased out shortly after

Other fighter types from the time:

• North American F-82F/G Twin Mustang
• North American F-86A/E/F Sabre
• Lockheed F-80C Shooting Star

When the F-84F was first introduced, it competed with World War II aircraft and other piston-driven models. At the outbreak of the Korean War, the only aircraft that had the range to reach the front line of the conflict from US bases in Japan was the North American F-82 Twin Mustang. The F-84F would serve alongside other World War II icons like the F-4U Corsair.

While it didn’t serve in the Second World War, the F-84F would serve alongside the A-1 Skyraider. The piston-driven aircraft would provide close air support in Korea and Vietnam.

Production Delays

Plagued by several issues during development

• New Engine
• Bad Canopy
• Fuselage Design

The F-84F’s production was riddled with difficulties, which caused the aircraft to be delayed several times. The J-65 engine was known to flame out during rain and snow, and a disproportionate number of tools had to be acquired to operate the jet, with the tools coming with the F-84. Given the rate of advancements in engine technology, the jet wasn’t spared from engine upgrades. The J-65 that flew in the first production aircraft would be upgraded through production, with each upgrade requiring further changes to the aircraft design.

The rear horizontal stabilizer was inadequate after modifications to the fuselage to accommodate the new larger engine. This resulted in the aircraft being declared not combat-ready until improvements were made to the stabilizer design.

Nevertheless, the F-84F was not without a legacy. The aircraft was used to set a time record between Los Angeles and New York on March 9th, 1955. At the same time, the newly formed Thunderbirds acquired the jet as an upgrade from their F-84G models. The legacy of the F-84F being used as a Thunderbirds aircraft was short-lived, however, due to the team swapping it out for the F-100 Super Sabre in 1956.

Source: National Museum of the US Air Force