Дуглас F4D Skyray: Американский палубный перехватчик

US carrier based jet powered interceptor

The Douglas F4D Skyray (later redesignated F 6 Skyray) is an American carrier based fighter/interceptor designed and produced by the Douglas Aircraft Company. It was the last fighter produced by the Douglas Aircraft Company prior to its merger with McDonnell Aircraft to become McDonnell Douglas. Development of the Skyray was started by Douglas during the late 1940s as the D 571 1 design study. It was a delta wing interceptor capable of a high rate of climb as to permit the rapid interception of approaching hostile bombers. Douglas' proposal was selected by Navy officials to fulfil a formal requirement issued in 1948. The decision to adopt the Westinghouse J40 turbojet engine to power it would lead to considerable difficulties later on as this engine would be cancelled prior to entering production. Aerodynamic issues would also lead to a protracted development cycle, considerable design changes being made even after the maiden flight of a production standard Skyray having taken place in June 1954. The Skyray was declared ready for fleet introduction in April 1956, permitting its entry to service with both the United States Navy (USN) and United States Marine Corps (USMC) shortly thereafter. The Skyray had a relatively brief service life, during which it never participated in actual combat. Despite this, it was the first carrier launched aircraft to hold the world's absolute speed record, having attained a top speed of 752.943 mph, (1,211.744 km/h). It also set a new time to altitude record, flying from a standing start to 49221 feet (15003 m) in two minutes and 36 seconds, all while flying at a 70° pitch angle. The last Skyrays were withdrawn from service in February 1964, although a handful continued to be flown for experimental purposes by National Advisory Committee for Aeronautics (NACA) up to the end of the decade. The F5D Skylancer was an advanced development of the F4D Skyray that ultimately did not enter service.

The Skyray originated within a design study, the D 571 1, performed by Douglas and funded by the United States Navy (USN). It was a fast climbing pure interceptor that used a delta wing configuration and powered by a pair of Westinghouse J34 turbojet engines, which were equipped with afterburners for bursts of additional acceleration. The D 571 1 had a relatively thick wing with no conventional fuselage save for a pod like cockpit in a forward position. A total of four 20mm cannons extended forward of the leading edge of the wing; alternative armaments consisted of spin stabilized rockets. In June 1947, the Navy issued a contract to Douglas to proceed with preliminary investigation and engineering works on the concept up to the mockup stage. As the design was refined, it was decided to reduce the wing's thickness substantially to increase its high speed capabilities. The twin J34 engine arrangement was also swapped out for a single Westinghouse J40 engine. Only a single hydraulic system was incorporated, thus measures to permit manual reversion in the event of hydraulic failure were also included. At the time, Navy planners were particularly concerned by the threat posed to its carrier battle groups by high altitude Soviet bomber aircraft; furthermore, as early jet aircraft were fuel hungry and had limited endurance, to maximise an interceptor aircraft time on station the Navy desired for such an aircraft to possess a relatively high rate of climb so that it could be launched and rapidly reach its operational altitude. On account of the numerous design changes, the mockup review was delayed by almost one year, taking place in March 1949. One criticism produced at this stage was that the nose up attitude was greater than had been anticipated, necessitating changes to the aircraft's nose and radome to improve the pilot's external visibility. this approach proved to be quite fortunate as the J40 had a particularly troubled development, being eventually cancelled with no production units ever being delivered. As a temporary measure, the prototype had to be outfitted with an Allison J35 engine instead. The ensuing delays to the programme led to several other aircraft, such as the North American F 100 Super Sabre and the Mikoyan Gurevich MiG 19, beating it into operational service. The thick wing roots contained the air intakes that fed its single turbojet engine. Fuel was contained both in the wings and the deep fuselage. Leading edge slats were fitted for increased lift during takeoff and landing while the trailing edges comprised mostly elevon control surfaces. Additional pitch trimmers were fitted inboard near the jet exhaust, and were locked upwards on takeoff and landing. It had a relatively unique design for the era, which was a key factor in the Skyray becoming one of the best known early jet fighters. It was affectionately known as the "Ford" (after the "Four" and "D" of its designation). During 1953, Edward H. Heinemann was awarded the Collier Trophy in recognition of his design work on the F4D.

During April 1956, VC 3 became the first squadron to attain operational status with the F4D 1. The Skyray was designed exclusively for the high altitude interception role, with a high rate and angle of climb. It set a new time to altitude record, flying from a standing start to 49221 feet (15003 m) in two minutes and 36 seconds, all while flying at a 70° pitch angle.

The F5D Skylancer was derived from the F4D and intended to be a Mach 2 capable successor to the Skyray. Although four prototypes were built and flown, the project was cancelled as being too similar in mission parameters to the F8U Crusader and also to reduce dependence upon Douglas Aircraft, which was also producing several other aircraft for the U. S. Navy. This decision effectively removed Douglas from active fighter development.