ALARM

ALARM (Air Launched Anti-Radiation Missile) is a British anti-radiation missile designed primarily to destroy enemy radars for the purpose of Suppression of Enemy Air Defense (SEAD). It is used by the RAF and the Royal Saudi Air Force.

History
The Ministry of Defence received bids for a new anti-radiation missile in late 1982; British Aerospace Dynamics offered ALARM while Texas Instruments teamed with Lucas Aerospace offered its HARM missile. Defence Secretary Michael Heseltine announced the selection of ALARM on 29 July 1983. The initial order was 750 missiles for the RAF. The selection process was controversial; the battle between the contractors was bitter, the Ministry of Defence favoured ALARM to retain UK industrial capabilities while the Treasury favoured the cheaper and proven HARM.

In early 1986 BAe recognised that Royal Ordnance was having difficulties delivering the missile's motor, named Nuthatch, and began to consider alternatives. Royal Ordnance's solution to the required burn-loiter-burn characteristic of the engine was complex. In July 1987 BAe, by then the owner of Royal Ordnance, replaced the Nuthatch motor with a lower risk motor designed by Bayern-Chemie. BAe's GB£200 million contract for the missile was renegotiated with the price increased to GB£400 million and delivery pushed back from 1988 to 1990.

Features
ALARM is a fire-and-forget system, with an added loiter capability. In loiter mode, ALARM will, when launched, climb to an altitude of 13 km. If the target radar shuts down, the missile will deploy a parachute and descend slowly until the radar lights up. The missile will then fire a secondary motor to attack the target.

Combat Performance
ALARM has been used in the following conflicts:
 * 1991 Gulf War, during which 121 missiles were used.
 * Kosovo War, during which 6 missiles were used.
 * 2003 Invasion of Iraq
 * 2011 Libya, shot down.

Operators

 * Royal Saudi Air Force
 * Royal Air Force
 * Royal Air Force
 * Royal Air Force

Specifications

 * Primary Function: Suppression of Enemy Air Defence
 * Contractor: MBDA
 * Power Plant: Bayern Chemie two stage solid propellant rocket motors
 * Length: 4.24 m
 * Diameter: 23 cm
 * Wing Span: 73 cm
 * Launch Weight: 268 kg
 * Speed: 2455 km/h (supersonic)
 * Warhead: Proximity fused high-explosive
 * Range: 93 km
 * Fuse: Laser Proximity
 * Guidance system: Pre-programmed/passive radar seeker
 * Unit Cost: undisclosed
 * Date Deployed: 1990
 * User: UK (RAF)
 * Tornado GR.4
 * Tornado F3 - fitted in time for 2003 Gulf War - receiving designation Tornado EF3
 * Weapon has been "fit checked" on other RAF aircraft, such as the Jaguar. Due to its relatively large weight it is not suited to the entire RAF fleet.
 * Also was expected to be usable on the Eurofighter Typhoon, but this requirement was deleted.

References in video games
ALARM inspired the 1993 flight simulator game Tornado. Both direct and loiter modes are supported. The modelling is fairly accurate, for instance in loiter the player will see the missile zoom climb and deploy its parachute before descending to the ground, or go on to attack a new radar source. In direct mode, the range for the missile is some 10nm and can only be fired at one target at a time.

ALARM is also found in EF2000 (computer game). Both modes are again supported.