The Grumman F9F/ F-9 Panther was Grumman’s first jet fighter, and the US Navy’s main fighter aircraft during the Korean War.
The F9F began life as the Grumman G-75 night fighter. This was to be powered by four 1,500lb thrust Westinghouse J30 engines, carried in two nacelles. The resulting aircraft would have looked rather similar to the Gloster Meteor, but with wider engine nacelles. A contract for this design, the XF9F-1, was issued on 22 April 1946, but Grumman were concerned about the engine installation.
As a result they began work on the G-79D design project. This was to use a single 5,000lb Rolls-Royce Nene engine carried in the fuselage. It had straight wings, mounted low on the fuselage, with the air intakes at the wing roots. Production aircraft had fixed fuel tanks on the end of the wings. The horizontal tail surface extended well behind the jet pipe. The vertical tail surfaces were mounted mid-way up the tail, again just behind the jet pipe.
This was submitted to the Navy in June 1946 and in September three prototypes were ordered, as the XF9F-2. Work on the prototypes began in February 1947. Two were to be built as the -2, powered by a Rolls Royce Nene engine licence built in America as the Pratt & Whitney J42 and one as the -3, powered by an Allison J33.
The Nene engines were delivered in July 1947, and the first prototype began taxiing trials on 20 November. On 24 November 1947 the aircraft made its maiden flight, with C.H. Corky Meyer at the controls. The aircraft took off from Grumman’s field at Bethpage, but landed on the longer runway at Idelwild Airport before returning to Bethpage once its landing characteristics had been checked. The aircraft then went to the Navy, and made its first flight with a Naval pilot on 18 March 1948. However the Navy was confident enough in the design to have ordered a batch of 30 production aircraft before the maiden flight of the first prototype.
The second prototype reached the Navy Air Test Centre in October 1948 to carry out carrier compatibility trials, but was lost after a problem with the fuel system on 28 October. However by this point the first production aircraft had been completed, and it was replaced by one of the first F9F-2s. Full carrier trials took place on the USS Franklin D. Roosevelt in March 1949. The F9F entered service with VF-51 on 8 May 1951.
The third prototype, powered by the 4,600lb thrust Allison J-33-A-8 made its maiden flight on 16 August 1948.
Two versions were ordered into production – 47 of the Nene powered F9F-2 and 54 of the Allison powered F9F-3. Both versions were produced at the same time, and the first production examples of both types made their maiden flights in November 1948. The Allison engine proved unsatisfactory, and the -3s were later converted into -2s.
The F9F was a conventional looking aircraft for its period. The straight wings were mid-mounted and tapered. The jet pipe emerged under the tail, which had mid-mounted horizontal surfaces. One innovation was the use of a ‘sliding tray’ system for the guns and other nose sections, which extended out 3 ½ feet to give easy access to the four 20mm cannon and other systems. The first six inches of the leading edge of the wing could be moved down to change the shape of the wings to improve its low speed handling for carrier landings.
The F9F wasn’t the first Navy jet – it had been beaten into the air by the McDonnell FH-1 Phantom, North American FK-1 Fury, Vought F6U-1 and McDonnell F2H Banshee, but it would be more successful than its first generation rivals and produced in larger numbers than any of them.
Soon after the F9F Panther entered service work began on a version with swept back wings. Rather confusingly this kept the F9F designation, but was given a new name, becoming the F9F Cougar. Variants of this model started with the F9F-6.
In the 1962 tri-service designation system the F9F became the F-9, but this only seems to have affected the F9F-5KD target drones and drone control aircraft.
The first operation squadron to receive the type was VF-51, which got its first F9F-3s in May 1949. VF-111 was the first to get the F9F-2. The Panther was also used by the Marines.
On 3 July 1950 an aircraft from VF-51 operating as part of Carrier Air Group 5 on USS Valley Forge flew the first carrier jet operation of the Korean War. VF-52 also used the F9F on the Valley Forge.
The F9F was used for a range of missions in Korea, including interdiction, combat air patrol around the fleet and escort for unarmed reconnaissance aircraft. Between June 1950 and July 1953 Panthers flew over 78,000 combat missions.
The type’s first combat success came on 3 July 1950 when an aircraft from VF-51 shot down two Yak-9s.
On 9 November 1950 Lt Commander Tom Amen of VF-111 became the first Navy jet pilot to shoot down a jet fighter, in this case a MiG-15.
By the end of the war twenty four squadrons had operated the straight winged F9F Panther from carriers off Korea. Marine Squadron VMA-334 had used the F9F-4 in combat.
After the F9F was replaced by the swept wing F9F Cougar the remaining Panthers were used for special duties, including as drones and drone controllers.
The F9F-2 was powered by the licence built Nene engine, designated as the Pratt & Whitney J42-P-6. A total of 567 were built. The first production aircraft flew on 24 November 1948. It carried two 120 gallon wing tip fuel tanks, had a pressurised cabin with ejector seat and was armed with four 20mm M-3 cannon in the nose. The -2 was underpowered and needed a catapult launch on calm days, when it could only carry a limited payload.
The F9F-2B was a ground attack version with hardpoints under the wings to carry various weapons. This designation was dropped when all aircraft were given the same hardpoints under the wings,
The F9F-3 was originally mean to be powered by the Allison J33-A-8. 54 were ordered, but the Allison engine proved to be unreliable and from February 1950 they were converted to F9F-2 standard.
The F9F-4 was powered by a water-injected 6,950lb thrust Allison J33-A-16 engine. It was also slightly longer, heavier and had a new straight fin and rudder. The prototype made its maiden flight six months later than planned, on 6 July 1950, again because of problems with the Allison engine. 73 F9F-4s were ordered, but most were completed as Rolls Royce Tay powered F9F-5s. The remained -4s went to the US Marines.
The F9F-5 was powered by a licence built Rolls-Royce Tay engine, built by Pratt & Whitney as the J48-P-2. The prototype made its maiden flight on 21 December 1949 and a total of 616 were built, making it the most numerous version of the Panther. They were delivered between 25 October 1951 and 11 August 1952.
The F9F-5P was an unarmed photo-reconnaissance aircraft, carrying cameras in the nose. 36 were delivered between 25 October 1951 and 13 January 1953.
After they were withdrawn from service some -5s were converted into target drones or drone control aircraft, as the F9F-5KD. In 1962 these aircraft became the DF-9E.
Engine: Pratt & Whitney J48-P-6A turbojet
Power: 6,250lb s.t
Length: 35ft 10in
Height: 12ft 3in
Empty weight: 10,147lb
Gross weight: 18,721lb
Max speed: 579mph at 5,000ft
Cruising speed: 481mph
Climb Rate: 5,090ft/in
Service ceiling: 42,800ft
Range: 1,300 miles
Armament: Four fixed forward firing 20mm gun