Pye Wacket was the codename for an experimental lenticular-form

air-to-air missile The newest and the oldest member of Rafael's Python family of AAM for comparisons, Python-5 (displayed lower-front) and Shafrir-1 (upper-back) An air-to-air missile (AAM) is a missile fired from an aircraft for the purpose of destroying a ...

developed by the

Convair Convair, previously Consolidated Vultee, was an American aircraft manufacturing company that later expanded into rockets and spacecraft. The company was formed in 1943 by the merger of Consolidated Aircraft and Vultee Aircraft. In 1953, it ...

Division of the

General Dynamics Corporation General Dynamics Corporation (GD) is an American publicly traded, aerospace and defense corporation headquartered in Reston, Virginia. As of 2020, it was the fifth-largest defense contractor in the world by arms sales, and 5th largest in the U ...

in 1957. Intended as a defensive missile for the

B-70 Valkyrie The North American Aviation XB-70 Valkyrie was the prototype version of the planned B-70 nuclear-armed, deep-penetration supersonic strategic bomber for the United States Air Force Strategic Air Command. Designed in the late 1950s by Nort ...

Mach 3 bomber, the program saw extensive

wind-tunnel Wind tunnels are large tubes with air blowing through them which are used to replicate the interaction between air and an object flying through the air or moving along the ground. Researchers use wind tunnels to learn more about how an aircraft ...

testing and seemed promising; however, the cancellation of the B-70 removed the requirement for the missile, and the project was cancelled.

Genesis

Project "Pye Wacket", officially known as the Lenticular Defense Missile (LDM) Program and by the project number WS-740A, was instituted in 1958 in response to a US Air Force request for a Defensive Anti-Missile System (DAMS) to protect the proposed

strategic bomber A strategic bomber is a medium- to long-range penetration bomber aircraft designed to drop large amounts of air-to-ground weaponry onto a distant target for the purposes of debilitating the enemy's capacity to wage war. Unlike tactical bombers, ...

from high-speed, high-altitude

surface-to-air missiles A surface-to-air missile (SAM), also known as a ground-to-air missile (GTAM) or surface-to-air guided weapon (SAGW), is a missile designed to be launched from the ground to destroy aircraft or other missiles. It is one type of anti-aircraft syst ...

(SAMs) and

interceptor aircraft An interceptor aircraft, or simply interceptor, is a type of fighter aircraft designed specifically for the defensive interception role against an attacking enemy aircraft, particularly bombers and reconnaissance aircraft. Aircraft that are cap ...

.Parsch 2005 The extreme speed and operating altitude of the Valkyrie was considered sufficient protection against Soviet interceptors of the time. However it was anticipated that future aircraft and missile developments would reduce the B-70's margin of superiority, especially following the

SA-2 Guideline The S-75 (Russian: С-75; NATO reporting name SA-2 Guideline) is a Soviet-designed, high-altitude air defence system, built around a surface-to-air missile with command guidance. Following its first deployment in 1957 it became one of the most w ...

SAM being displayed during the 1957

May Day parade May Day is a European festival of ancient origins marking the beginning of summer, usually celebrated on 1 May, around halfway between the spring equinox and summer solstice. Festivities may also be held the night before, known as May Eve. T ...

. Intelligence reports indicated that SAMs were being deployed in large numbers throughout Russia, and it was believed the SA-2 was capable of being fitted with a nuclear

warhead A warhead is the forward section of a device that contains the explosive agent or toxic (biological, chemical, or nuclear) material that is delivered by a missile, rocket, torpedo, or bomb. Classification Types of warheads include: * Explosiv ...

. Therefore, it was decided that the B-70 would need an interceptor missile to defend itself against the perceived threat.

Design

Main structure weldment of PYE WACKET Feasibility Test Vehicle Study (Summary) 15 February 1961

The specifications for the proposed DAMS called for an air-launched defensive missile, capable of engaging incoming missiles at relative speeds of up to Mach 7, surviving a rate of acceleration between 60 g to 250 g, and being able to undertake rapid terminal-phase guidance changes in any direction. Following initial studies and wind-tunnel testing at the

Air Proving Ground Center The Air Armament Center (AAC) was an Air Force Materiel Command (AFMC) center at Eglin Air Force Base, Florida, responsible for development, acquisition, testing, and deployment of all air-delivered weapons for the U.S. Air Force. Weapon system ...

and

Arnold Engineering Development Center The Arnold Engineering Development Complex (AEDC), Arnold Engineering Development Center before July 2012, is an Air Force Materiel Command facility under the control of the Air Force Test Center (AFTC). Headquartered at Arnold Air Force Base, ...

, a radically unconventional design emerged that featured a lenticular, wedge-shaped airframe. The lenticular design was considered to have the best handling characteristics at extremely high

angles of attack In fluid dynamics, angle of attack (AOA, α, or \alpha) is the angle between a reference line on a body (often the chord line of an airfoil) and the vector representing the relative motion between the body and the fluid through which it is m ...

, and would theoretically possess ideal mass distribution, giving the missile outstanding terminal agility. In addition, the lenticular design allowed for omnidirectional launching from the carrying aircraft.USAF 1961. Following the feasibility studies, a contract for the development of the DAMS design was awarded to the Convair division of the General Dynamics Corporation in

Pomona, California Pomona is a city in Los Angeles County, California. Pomona is located in the Pomona Valley, between the Inland Empire and the San Gabriel Valley. At the 2020 census, the city's population was 151,713. The main campus of California State Polyte ...

in 1959. Wind tunnel testing of several options for control of the missile resulted in an arrangement of six small rocket thrusters being selected for reaction control. The airframe of the missile was constructed of

magnesium alloy Magnesium alloys are mixtures of magnesium (the lightest structural metal) with other metals (called an alloy), often aluminium, zinc, manganese, silicon, copper, rare earths and zirconium. Magnesium alloys have a hexagonal lattice structure, w ...

, and main power would be provided by three

Thiokol M58 Thiokol (variously Thiokol Chemical Corporation(/Company), Morton Thiokol Inc., Cordant Technologies Inc., Thiokol Propulsion, AIC Group, ATK Thiokol, ATK Launch Systems Group; finally Orbital ATK before becoming part of Northrop Grumman) was an ...

A2 solid-fuel rockets.

Cancellation

Pye Wacket was planned to be tested using a

rocket sled launch A rocket sled launch, also known as ground-based launch assist, catapult launch assist, and sky-ramp launch, is a proposed method for launching space vehicles. With this concept the launch vehicle is supported by an eastward pointing rail or ma ...

er, with a Mach 5 booster rocket being used later in the test program. There are unconfirmed reports that some tests were conducted in 1960. However the high cost and perceived vulnerability of the B-70 against the projected performance of Soviet air defenses,Greenwood 1995, p.289. combined with the

1960 U-2 incident On 1 May 1960, a United States U-2 spy plane was shot down by the Soviet Air Defence Forces while conducting photographic aerial reconnaissance deep inside Soviet territory. The single-seat aircraft, flown by American pilot Francis Gary Power ...

in which a high-flying spyplane had been shot down, led to the decision that

intercontinental ballistic missiles An intercontinental ballistic missile (ICBM) is a ballistic missile with a range greater than , primarily designed for nuclear weapons delivery (delivering one or more thermonuclear warheads). Conventional, chemical, and biological weapons c ...

would, in the future, be the primary nuclear delivery force of the United States, and therefore the B-70 project was cancelled in early 1961.Kennedy, John F
"Remarks of Senator John F. Kennedy, Horton Plaza, San Diego, CA , November 2, 1960."
The American Presidency Project at ucsb.edu. Retrieved: 6 April 2009.

"1961 Budget Message."

Kennedy Archives
'', 28 March 1961, pp. I-38. Pye Wacket, its delivery vehicle no longer available, is believed to have been cancelled soon after, although the ultimate fate of the program remains classified.

References

Notes

Bibliography

* * *General Dynamics; Convair/Pomona Division (July 1961).
Pye Wacket. Feasibility Test Vehicle Study
'. Summary. Volume 1. Reproduced by Defense Technical Information Center. Retrieved on May 22, 2009. * * * * *US Air Force (1961)

'. II-24, IL-25. Reproduced per request to Air Force Historical Research Agency. Retrieved on May 22, 2009.

External References

{{USAF missiles Abandoned military rocket and missile projects of the United States Cold War air-to-air missiles of the United States Experimental missiles Flying saucers General Dynamics