1954 interceptor
Encyclopedia
The 1954 interceptor, formally WS-201A, was a US Air Force project to develop a dedicated interceptor aircraft
Interceptor aircraft
An interceptor aircraft is a type of fighter aircraft designed specifically to prevent missions of enemy aircraft, particularly bombers and reconnaissance aircraft. Interceptors generally rely on high speed and powerful armament in order to complete their mission as quickly as possible and set up...

 that would enter service in 1954. Several aircraft were developed as part of the project, leading to the F-102 Delta Dagger
F-102 Delta Dagger
The Convair F-102 Delta Dagger was a US interceptor aircraft built as part of the backbone of the United States Air Force's air defenses in the late 1950s. Entering service in 1956, its main purpose was to intercept invading Soviet bomber fleets...

, F-106 Delta Dart
F-106 Delta Dart
The Convair F-106 Delta Dart was the primary all-weather interceptor aircraft for the United States Air Force from the 1960s through the 1980s. Designed as the so-called "Ultimate Interceptor", it has proven to be the last dedicated interceptor in USAF service to date...

, XF-103 Thunderwarrior
Republic XF-103
The Republic XF-103 was an American project to develop a high speed interceptor aircraft capable of destroying Soviet bombers. Despite a prolonged development, it never progressed past the mock-up stage.-Development:...

 and, indirectly, the F-101B Voodoo and F-104 Starfighter
F-104 Starfighter
The Lockheed F-104 Starfighter is a single-engine, high-performance, supersonic interceptor aircraft originally developed for the United States Air Force by Lockheed. One of the Century Series of aircraft, it served with the USAF from 1958 until 1969, and continued with Air National Guard units...

. The electronics and weapons were also destined to become common, including the AIM-4 Falcon
AIM-4 Falcon
The Hughes AIM-4 Falcon was the first operational guided air-to-air missile of the United States Air Force.-Development:Development of a guided air-to-air missile began in 1946. Hughes Aircraft was awarded a contract for a subsonic missile under the project designation MX-798, which soon gave way...

 missile and a variety of Hughes Electronics supplied radar
Radar
Radar is an object-detection system which uses radio waves to determine the range, altitude, direction, or speed of objects. It can be used to detect aircraft, ships, spacecraft, guided missiles, motor vehicles, weather formations, and terrain. The radar dish or antenna transmits pulses of radio...

 and fire control
Fire control
control of fire 'control of fire' is the practice of reducing the heat output of a fire, or reducing the area over which the fire exists, or suppressing or extinguishing the fire by depriving a fire of fuel, oxygen or heat ....

 systems. The project also led, eventually, to the upgrading of the SAGE
Semi Automatic Ground Environment
The Semi-Automatic Ground Environment was an automated control system for tracking and intercepting enemy bomber aircraft used by NORAD from the late 1950s into the 1980s...

 battle control computers to directly control the interceptors for much of their flight. Although greatly delayed, the resulting systems operated for about 20 years, into the 1980s.

Background

The "1954 interceptor" concept first appeared shortly after the creation of the Air Force from the former US Army Air Force in the post-World War II
World War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...

 era. With the re-arrangement of command, several new organizations within the Air Force were created, including Tactical Air Command
Tactical Air Command
Tactical Air Command is an inactive United States Air Force organization. It was a Major Command of the United States Air Force, established on 21 March 1946 being headquartered at Langley Air Force Base, Virginia...

 (TAC) and Air Defense Command (ADC), who shared an interest in fighter aircraft
Fighter aircraft
A fighter aircraft is a military aircraft designed primarily for air-to-air combat with other aircraft, as opposed to a bomber, which is designed primarily to attack ground targets...

. TAC was primarily tasked with offensive duties, but required capable fighters in order to protect their offensive capability. ADC was tasked solely with the defense of the US from enemy attack, in particular long-distance bomber
Bomber
A bomber is a military aircraft designed to attack ground and sea targets, by dropping bombs on them, or – in recent years – by launching cruise missiles at them.-Classifications of bombers:...

s. Soon after their formation, TAC and ADC started moving away from each other in terms of requirements.

In early 1949 ADC started a Request for Proposals (RFP) for an advanced interceptor capable of attacking Soviet bombers that were expected to enter service in the early 1950s. Several jet-powered interceptors were already under development at that point, typically adaptations of existing fighters like the F-86 Sabre
F-86 Sabre
The North American F-86 Sabre was a transonic jet fighter aircraft. Produced by North American Aviation, the Sabre is best known as America's first swept wing fighter which could counter the similarly-winged Soviet MiG-15 in high speed dogfights over the skies of the Korean War...

 (the D model), the F-94 Starfire
F-94 Starfire
The Lockheed F-94 Starfire was the United States Air Force's first operational jet-powered all-weather interceptor aircraft. It was a development by Lockheed of the twin-seat T-33 Shooting Star trainer aircraft.-Design and development:...

 (adapted from the P-80 Shooting Star
P-80 Shooting Star
The Lockheed P-80 Shooting Star was the first jet fighter used operationally by the United States Army Air Forces. Designed in 1943 as a response to the German Messerschmitt Me-262 jet fighter, and delivered in just 143 days from the start of the design process, production models were flying but...

), with the exception being the all-new F-89 Scorpion
F-89 Scorpion
The Northrop F-89 Scorpion was an early American jet-powered fighter designed from the outset as an all-weather interceptor. Though its straight wings limited its performance, it was among the first USAF jet fighters with guided missiles, and notably the first combat aircraft armed with air-to-air...

. However these were all subsonic aircraft, and it was felt they would have insufficient performance to effectively intercept high-speed jet bombers known to be under development in the Soviet Union
Soviet Union
The Soviet Union , officially the Union of Soviet Socialist Republics , was a constitutionally socialist state that existed in Eurasia between 1922 and 1991....

.

To counter these threats, ADC prepared a request for an entirely new aircraft expected to perform "hot war" interceptions at supersonic
Supersonic
Supersonic speed is a rate of travel of an object that exceeds the speed of sound . For objects traveling in dry air of a temperature of 20 °C this speed is approximately 343 m/s, 1,125 ft/s, 768 mph or 1,235 km/h. Speeds greater than five times the speed of sound are often...

 speeds. For reasons that are not clear, they also demanded that the entire system be flown and operated by a single pilot. Given the complexity of the radar systems and the aircraft themselves, this would require an advanced autopilot
Autopilot
An autopilot is a mechanical, electrical, or hydraulic system used to guide a vehicle without assistance from a human being. An autopilot can refer specifically to aircraft, self-steering gear for boats, or auto guidance of space craft and missiles...

 system that was integrated with the fire control system to lower pilot workload. Given the perceived threat, the new designs were expected to enter service in 1954.

WS-201A

The Air Force had already realized that the complexity of these newer systems would make integration difficult. In the past, aircraft airframes, engines and weapons were fairly common in size and general layout, allowing existing designs to be modified to change any one component with relative ease. For the 1954 interceptor, new equipment such as missiles and radar systems would be radically different between designs. There was little expectation that one missile could be swapped for another, for instance, due both to different electronic requirements as well as different mechanical layout.

To deal with this problem the Air Force introduced the "Weapons Systems" concept, where an entire aircraft (or other system) would be ordered as a complete working assembly. Although the parts going into it would be ordered under separate contracts, the requirements of the system as a whole would be known to all of the participants in advance, and one of the companies would be considered "prime" on ensuring all the parts would fit when they were delivered. The 1954 interceptor was the first fighter aircraft ordered under the Weapon System concept, and became "WS-201A". Contracts for the various parts making up 201A were sent out as soon as they completed writing them up, starting with the electronics suite, then the missile, and finally airframe and engine.

Studies of the electronics suite had started in February 1949, prior to the 201A specification, and were folded into the project. In January 1950 they sent out the MX-1179 contract tender to eighteen electronics contractors, but only Bendix
Bendix
- People :* Bendix Hallenstein - New Zealand businessman* Henry Bendix - fictional character from Wildstorm comics* John E. Bendix - American Civil War and New York Guard general* Max Bendix - American composer, conductor, violinist* Reinhard Bendix - sociologist...

, General Electric
General Electric
General Electric Company , or GE, is an American multinational conglomerate corporation incorporated in Schenectady, New York and headquartered in Fairfield, Connecticut, United States...

, Hughes Electronics, North American Aviation
North American Aviation
North American Aviation was a major US aerospace manufacturer, responsible for a number of historic aircraft, including the T-6 Texan trainer, the P-51 Mustang fighter, the B-25 Mitchell bomber, the F-86 Sabre jet fighter, the X-15 rocket plane, and the XB-70, as well as Apollo Command and Service...

, Sperry
Sperry
-Persons:*Armstrong Sperry , American author and illustrator*Brett Sperry , American video game designer*Carlos A. Sperry, Democratic President of the West Virginia Senate from Greenbrier County, served 1872-1872...

, and Westinghouse responded. Hughes was announced as the winner in July 1950, with what would become the MA-1. The original contract specified that MX-1179 would "direct some type of air-to-air guided missile." Hughes had already won the MX-904 contract for a missile known as the GAR-1 Falcon, and this was selected for 201A mainly because it seemed to be the only one that could be ready in time to meet the 1954 operational date.

The airframe and engine contract was issued as MX-1554 on 18 June 1950, with a January 1951 deadline for submissions. MX-1554 also stated that the winner of the airframe contract would also be named the lead "integrator" of the overall Weapon System. When the deadline was reached, nine different proposals were submitted; Republic Aircraft entered three designs, North American two, and Chance-Vought, Convair
Convair
Convair was an American aircraft manufacturing company which later expanded into rockets and spacecraft. The company was formed in 1943 by the merger of Vultee Aircraft and Consolidated Aircraft, and went on to produce a number of pioneering aircraft, such as the Convair B-36 bomber, and the F-102...

, Douglas
Douglas Aircraft Company
The Douglas Aircraft Company was an American aerospace manufacturer, based in Long Beach, California. It was founded in 1921 by Donald Wills Douglas, Sr. and later merged with McDonnell Aircraft in 1967 to form McDonnell Douglas...

, and Lockheed
Lockheed Corporation
The Lockheed Corporation was an American aerospace company. Lockheed was founded in 1912 and later merged with Martin Marietta to form Lockheed Martin in 1995.-Origins:...

 each submitted a single design. On 2 July 1951 the Air Force announced that Convair, Lockheed, and Republic had been selected to continue development through the mockup stage, and a winner would be selected at that point.

A short while later, the Air Force decided that it also needed a day fighter
Day fighter
A day fighter is a fighter aircraft equipped only to fight during the day. More specifically, it refers to a multi-purpose aircraft that does not include equipment for fighting at night , although it is sometimes used to refer to some interceptors as well.Examples of planes that were classified as...

 to combat the new MiG-15's that were being encountered over Korea
Korea
Korea ) is an East Asian geographic region that is currently divided into two separate sovereign states — North Korea and South Korea. Located on the Korean Peninsula, Korea is bordered by the People's Republic of China to the northwest, Russia to the northeast, and is separated from Japan to the...

. Existing designs like the P-80 Shooting Star
P-80 Shooting Star
The Lockheed P-80 Shooting Star was the first jet fighter used operationally by the United States Army Air Forces. Designed in 1943 as a response to the German Messerschmitt Me-262 jet fighter, and delivered in just 143 days from the start of the design process, production models were flying but...

 and F-84 Thunderjet
F-84 Thunderjet
The Republic F-84 Thunderjet was an American turbojet fighter-bomber aircraft. Originating as a 1944 United States Army Air Forces proposal for a "day fighter", the F-84 flew in 1946...

 were completely outperformed by the MiG, and while the newer F-86 Sabre
F-86 Sabre
The North American F-86 Sabre was a transonic jet fighter aircraft. Produced by North American Aviation, the Sabre is best known as America's first swept wing fighter which could counter the similarly-winged Soviet MiG-15 in high speed dogfights over the skies of the Korean War...

 was more than capable of holding its own, it was not clear that would be the case in a war situation in Europe against "front line" Soviet pilots. A plane of considerably higher performance would be needed to guarantee leadership in this role, so the Lockheed entry was redirected toward a day fighter role, evolving into the F-104 Starfighter. Convair and Republic continued on with the original MX-1554.

It quickly became clear that the Republic design was far too advanced for the 1954 operational entry deadline, and on 11 September 1951 the Convair design was selected as the MX-1554 airframe and was designated F-102. Republic was to continue development of their much more powerful design at a lower priority, becoming the F-103. With the introduction of these programs, work on the Republic XF-91A, originally slated as an interim interceptor, ended in October 1951 in favor of the new designs.

Although the F-102 had been selected as the "low tech" solution in order to meet the 1954 deadline, practically every part of the 201A system ran into delays. To start with, it was clear that the engine, a Wright-modified version of the Bristol Olympus known as the J67, would almost certainly not be ready in time for a 1954 service entry. Additionally, the MX-1179 fire-control system seemed to be a risky proposition, and was another source of potential delay. In December the Air Force decided to reduce the risk by splitting the program in two, producing a reduced-performance version with interim engines and fire control as an "Interim Interceptor", and continuing with the original design over a longer period of time as the "Ultimate Interceptor". The Interim design would use the Westinghouse J40
Westinghouse J40
|-References:...

 engine, already available although of low power, and the Hughes E-9 fire-control system, a slightly updated version of the system being used in the F-86D.

Meanwhile practically every part of the F-103 program was going wrong. Construction of the airframe required extensive use of titanium
Titanium
Titanium is a chemical element with the symbol Ti and atomic number 22. It has a low density and is a strong, lustrous, corrosion-resistant transition metal with a silver color....

 in order to handle the high heat loads of extended Mach 3+ flight speeds, and this proved much more difficult to work with than originally expected. The engine, a combination of a Wright-modified version of the Bristol Olympus and a "combined cycle" ramjet
Ramjet
A ramjet, sometimes referred to as a stovepipe jet, or an athodyd, is a form of airbreathing jet engine using the engine's forward motion to compress incoming air, without a rotary compressor. Ramjets cannot produce thrust at zero airspeed and thus cannot move an aircraft from a standstill...

 from Marquardt, also ran into extensive problems and the J67 eventually ended in failure. Nevertheless the expected performance was so high the program was allowed to soldier on.

Interim measures

The delays seriously upset the original timetable, and it was clear by 1952 that even the "low tech" F-102 would not be able to meet the 1954 deadline. Although it was expected that the F-102B would be an excellent long-term solution, something was needed quickly to fill the performance gap between the existing subsonic designs and the continuing delays in the existing F-102 design. ADC argued that having a second design would also guarantee that problems in either program would be less likely to effect the defense as a whole.

The only design with the needed performance at that point in time was the McDonnell F-88. This design had originally been ordered by Strategic Air Command
Strategic Air Command
The Strategic Air Command was both a Major Command of the United States Air Force and a "specified command" of the United States Department of Defense. SAC was the operational establishment in charge of America's land-based strategic bomber aircraft and land-based intercontinental ballistic...

 (SAC) as a long-range "penetration fighter" to escort their heavy bombers. When newer bomber designs offered performance so great that the F-88 could not hope to keep up with them, TAC then took over the work and started modifying it as a low-level nuclear-armed fighter-bomber
Fighter-bomber
A fighter-bomber is a fixed-wing aircraft with an intended primary role of light tactical bombing and also incorporating certain performance characteristics of a fighter aircraft. This term, although still used, has less significance since the introduction of rockets and guided missiles into aerial...

, renaming it as the F-101 Voodoo
F-101 Voodoo
The McDonnell F-101 Voodoo was a supersonic military jet fighter which served the United States Air Force and the Royal Canadian Air Force...

 in 26 November 1951.

ADC also became interested in the Voodoo in October 1952, but funding from higher headquarters was difficult to find. They rejected modifying the F-101, mainly due to its high cost, and suggested attempting solving the problem by increasing the numbers of F-86Ds and speeding up work on the F-102. In April ADC once again asked for the F-101, this time justifying it as a longer-range counterpart for use in areas not widely covered by radar. It appears this suggestion was also rejected.

However, in August 1953 the Soviets detonated their first hydrogen bomb, and ADC's concerns became considerably more urgent. The Air Force Council issued proposals to industry for a new design to work alongside the F-102 that would help fill the gap between the F-89 and F-106. After short consideration of alternatives — an updated F-89 and an interceptor version of F-100 — the two-seat modification of F-101 was finally selected for development. Known as F-101B, it would be equipped with the MG-3/Falcon suite from the F-102, but operated by a weapons officer instead of the pilot. It would greatly simplify the complexity of the system as a whole.

Continued problems

Work on the airframes continued through 1952 and into 1953. NACA wind tunnel tests in early 1953 showed that the maximum altitude of 57,000 feet and combat radius of 350 miles predicted by Convair were too optimistic. Drag turned out to be higher than expected, but NACA was able to suggest the application of the recently-developed area rule
Area rule
The Whitcomb area rule, also called the transonic area rule, is a design technique used to reduce an aircraft's drag at transonic and supersonic speeds, particularly between Mach 0.75 and 1.2....

 to combat this problem. Convair did not immediately put these recommendations into effect, and the initial two flying prototypes, of an order of 42 aircraft, continued with the original design. When these flew starting in October 1953, NACA's estimates were proven correct, and the F-102 had only a marginal performance improvement over the F-86D it was supposed to replace.

See also

  • Operational Requirement F.155
    Operational Requirement F.155
    Operational Requirement F.155 was a specification issued by the British Ministry of Supply for an interceptor aircraft to defend the United Kingdom from high-flying supersonic bombers....

    - British interceptor program of 1955
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