Korean War: Grumman F9F Panther

F9F Panther in flight
Grumman F9F Panther. US Navy

Having had success in building fighters for the US Navy during World War II with models such as the F4F Wildcat, F6F Hellcat, and F8F Bearcat, Grumman began work on its first jet aircraft in 1946. Responding to a request for a jet-powered night fighter, Grumman's first effort, dubbed G-75, intended to utilize four Westinghouse J30 jet engines mounted in the wings. The large number of engines was necessary as the output of early turbojets was low. As the design progressed, advances in technology saw the number of engines reduced to two.

Designated XF9F-1, the night fighter design lost a competition to the Douglas XF3D-1 Skyknight. As a precaution, the US Navy ordered two prototypes of the Grumman entry on April 11, 1946. Recognizing that the XF9F-1 had key flaws, such as a lack of space for fuel, Grumman commenced evolving the design into a new aircraft. This saw the crew reduced from two to one and the elimination of night-fighting equipment. The new design, the G-79, moved forward as a single-engine, single-seat day fighter. The concept impressed the US Navy which amended the G-75 contract to include three G-79 prototypes.

Development

Assigned the designation XF9F-2, the US Navy requested that two of the prototypes be powered by the Rolls-Royce "Nene" centrifugal-flow turbojet engine. During this time, work was moving forward to allow Pratt & Whitney to build the Nene under license as the J42. As this had not been completed, the US Navy asked that the third prototype be powered by a General Electric/Allison J33. The XF9F-2 first flew on November 21, 1947 with Grumman test pilot Corwin "Corky" Meyer at the controls and was powered by one of the Rolls-Royce engines.

The XF9F-2 possessed a mid-mounted straight-wing with leading edge and trailing edge flats. Intakes for the engine were triangular in shape and situated in wing root. The elevators were mounted high on the tail. For landing, the aircraft utilized a tricycle landing gear arrangement and a "stinger" retractable arresting hook. Performing well in testing, it proved capable of 573 mph at 20,000 feet. As trials moved forward, it was found that the aircraft still lacked the necessary fuel storage. To combat this issue, permanently mounted wingtip fuel tanks were mounted to the XF9F-2 in 1948.

The new aircraft was named "Panther" and mounted a base armament of four 20mm cannon which were aimed using a Mark 8 computing optical gunsight. In addition to the guns, the aircraft was capable of carrying a mix of bombs, rockets, and fuel tanks under its wings. In total, the Panther could mount 2,000 pounds of ordnance or fuel externally, though the due to a lack of power from the J42, F9Fs seldom launched with a full load.

Production:

Entering service in May 1949 with VF-51, the F9F Panther passed its carrier qualifications later that year. While the first two variants of the aircraft, the F9F-2 and F9F-3, differed only in their power plants (J42 vs. J33), the F9F-4 saw the fuselage lengthened, tail enlarged, and the inclusion of the Allison J33 engine. This was later superseded by the F9F-5 which used the same airframe but incorporated a license-built version of the Rolls-Royce RB.44 Tay (Pratt & Whitney J48).

While the F9F-2 and F9F-5 became the main production models of the Panther, reconnaissance variants (F9F-2P and F9F-5P) were also constructed. Early in the Panther's development, concern arose regarding the aircraft's speed. As a result, a swept-wing version of the aircraft was also designed. Following early engagements with the MiG-15 during the Korean War, work was accelerated and the F9F Cougar produced. First flying in September 1951, the US Navy viewed the Cougar as a derivative of the Panther hence its designation as F9F-6. Despite the accelerated development timeline, F9F-6s did not see combat in Korea.

Specifications (F9F-2 Panther):

General

  • Length: 37 ft. 5 in.
  • Wingspan: 38 ft.
  • Height: 11 ft. 4 in.
  • Wing Area: 250 ft²
  • Empty Weight: 9,303 lbs.
  • Loaded Weight: 14,235 lbs.
  • Crew: 1

Performance

  • Power Plant: 2 × Pratt & Whitney J42-P-6/P-8 turbojet
  • Combat Radius: 1,300 miles
  • Max. Speed: 575 mph
  • Ceiling: 44,600 ft.

Armament

  • 4 × 20 mm M2 cannon
  • 6 × 5 in. rockets on underwing hardpoints or 2,000 lbs. of bomb

Operational History:

Joining the fleet in 1949, the F9F Panther was the US Navy's first jet fighter. With the US entry into the Korean War in 1950, the aircraft immediately saw combat over the peninsula. On July 3, a Panther from USS Valley Forge (CV-45) flown by Ensign E.W. Brown scored the aircraft's first kill when he downed a Yakovlev Yak-9 near Pyongyang, North Korea. That fall, Chinese MiG-15s entered the conflict. The fast, swept-wing fighter out-classed the US Air Force's F-80 Shooting Stars as well as older piston-engine aircraft such as the F-82 Twin Mustang. Though slower than the MiG-15, US Navy and Marine Corps Panthers proved capable of combating the enemy fighter. On November 9, Lieutenant Commander William Amen of VF-111 downed a MiG-15 for the US Navy's first jet fighter kill.

Due to the MiG's superiority, the Panther was forced to hold the line for part of the fall until the USAF could rush three squadrons of the new North American F-86 Sabre to Korea. During this time, the Panther was in such demand that the Navy Flight Demonstration Team (The Blue Angels) was forced to turn over its F9Fs for use in combat. As the Sabre increasingly took over the air superiority role, the Panther began to see extensive use as a ground attack aircraft due to its versatility and hefty payload. Famous pilots of the aircraft included future astronaut John Glenn and Hall of Famer Ted Williams who flew as wingmen in VMF-311. The F9F Panther remained the US Navy and Marine Corps' primary aircraft for the duration of the fighting in Korea.

As jet technology rapidly advanced, the F9F Panther began to be replaced in American squadrons in the mid-1950s. While the type was withdrawn from frontline service by the US Navy in 1956, it remained active with the Marine Corps until the following year. Though used by reserve formations for several years, the Panther also found use as a drone and drone tug into the 1960s. In 1958, the United States sold several F9Fs to Argentina for use aboard their carrier ARA Independencia (V-1). These remained active until 1969. A successful aircraft for Grumman, the F9F Panther was the first of several jets the company provided for the US Navy, with the most famous being the F-14 Tomcat.