The AS-20 was a French

France

The French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France...

 air-to-surface missile

Air-to-surface missile

An air-to-surface missile is a missile designed to be launched from military aircraft and strike ground targets on land, at sea, or both...

 developed during the late 1950s. It was similar to the U.S. AGM-12 Bullpup

AGM-12 Bullpup

The AGM-12 Bullpup is an air-to-ground missile which was used on the A-4 Skyhawk, A-6 Intruder, F-105 Thunderchief and F-4 Phantom among others...

 missile.

Development

The AS-20 was based on an earlier Nord Aviation

Nord Aviation

Nord-Aviation was a state-owned French aircraft manufacturer. It was created on October 1, 1954 upon the acquisition of SFECMAS by SNCAN...

 air-to-air missile

Air-to-air missile

An air-to-air missile is a missile fired from an aircraft for the purpose of destroying another aircraft. AAMs are typically powered by one or more rocket motors, usually solid fuelled but sometimes liquid fuelled...

 the AA.20

AA.20

The AA.20 was a French air-to-air missile, developed by Nord Aviation, and was one of the first such missiles adopted into services in Western Europe. Production began at Chatillon, France in 1956...

 (designated Type 5103). Only minor changes were required to make it an air-to-surface missile, the size of the warhead

Warhead

The term warhead refers to the explosive material and detonator that is delivered by a missile, rocket, or torpedo.- Etymology :During the early development of naval torpedoes, they could be equipped with an inert payload that was intended for use during training, test firing and exercises. This...

 was increased as a result of replacing the large proximity fuze

Proximity fuze

A proximity fuze is a fuze that is designed to detonate an explosive device automatically when the distance to target becomes smaller than a predetermined value or when the target passes through a given plane...

 with a simple impact fuze.

Design

The AS-20 had four steeply swept-back fins, cruciform in cross-section

Geometry

Geometry arose as the field of knowledge dealing with spatial relationships. Geometry was one of the two fields of pre-modern mathematics, the other being the study of numbers ....

 around the mid section of its body. It used a dual-thrust

Dual-thrust

In a dual-thrust solid fuel rocket motor, the propellant mass is composed of two different types or densities of fuel. In the case of a tandem dual-thrust motor, the fuel closest to the rocket nozzle burns fast and the fuel further into the motor's body burns slower...

 solid rocket motor, which exhaust

Exhaust system

An exhaust system is usually tubing used to guide reaction exhaust gases away from a controlled combustion inside an engine or stove. The entire system conveys burnt gases from the engine and includes one or more exhaust pipes...

ed through two large nozzles during the boost stage, and a single center line nozzle during the sustain stage. The AS-20 uses a simple MCLOS

MCLOS

MCLOS is a first-generation method for guiding guided missiles.With an MCLOS missile, the operator must track the missile and the target simultaneously and guide the missile to the target. Typically the missile is steered with a joystick, and its path is observed through a periscope-type...

 guidance with the pilot aligning the flares on the missile's rear with the target and controlling the missile in flight after launch with a small joystick

Joystick

A joystick is an input device consisting of a stick that pivots on a base and reports its angle or direction to the device it is controlling. Joysticks, also known as 'control columns', are the principal control in the cockpit of many civilian and military aircraft, either as a center stick or...

 sending steering command's to the missile via a radio link. The steering command's steer the missile back to the line-of-sight by thrust vectoring

Thrust vectoring

Thrust vectoring, also thrust vector control or TVC, is the ability of an aircraft, rocket or other vehicle to manipulate the direction of the thrust from its engine or motor in order to control the attitude or angular velocity of the vehicle....

 by the movement of one of four metal vanes around the center sustainer nozzle. The missile's internal gyro gives the missile command unit, the correct position of the missile in flight, and to which of the four thrust vanes to actuate at the correct time.

Operational history

Approximately 8,000 of the missiles were built, with the missile entering service in 1961. The AS-20 was one of the primary weapons of the Fiat G.91 of the West German Air Force and Italian Air Force during the 1960s and 1970s. It was phased out of service in most countries in the 1970s, being replaced in France by the larger AS-30

AS-30L

The AS-30L is a French short-to-medium range air-to-ground missile which employees laser homing guidance. The AS-30L was a development of the earlier 1970s AS-30 missile, which uses MCLOS guidance via a radio command link between the aircraft to the missile. The only difference between the AS-30...

.