The MIM-72A missile was based on the AIM-9D Sidewinder. The main difference is that to reduce drag only two of the fins on the MIM-72A have rollerons, the other two having been replaced by non-moving thin fins. The MIM-72's MK 50 solid-fuel rocket motor was essentially identical to the MK 36 MOD 5 used in the AIM-9D Sidewinder. The MIM-72 missile is launched from the M48 fire unit, consisting of a M730 tracked vehicle fitted with an M54 missile launcher capable of holding four missiles ready to fire. The M48 carries an additional eight missiles stowed.
General characteristics (MIM-72A)
- Length: 2.90 metres (9 ft 6 in)
- Wingspan: 63.0 centimetres (24.8 in)
- Diameter: 127 millimetres (5.0 in)
- Launch weight: 86 kilograms (190 lb)
- Speed: Mach 1.5
- Range: 500 to 9,000 metres (1,600 to 30,000 ft)
- Altitude: 25 to 4,000 metres (82 to 13,000 ft)
- Guidance: Passive infra-red tail chase only.
- Motor : MK 50 solid-fuel rocket motor (12.2 kN) for 4.7 s
- Warhead: 12.2 kilograms (27 lb) MK 48 Continuous-rod warhead
The MIM-72A like the FIM-43 Redeye uses a first generation infra-red seeker, and can be fooled by flares and "hot brick" jammers, such as the L166 IRCM unit fitted to the Mi-24. Also the missile needs to be able to see the hot exhaust of an aircraft, making it a tail chase only missile. A similar B model for training was identical to the A model with the exception of a different warhead fuze.
The C version of the missile, from 1974, has an improved guidance section that gives the missile an all-aspect capability, as well as a new doppler radar fuze and an improved warhead. The fuze and warhead were adapted from the earlier Mauler program. C models were deployed between 1976 and 1981, reaching operational status in 1978. An experimental D model used the warhead from the C version with the seeker from the A model, but was not deployed.
A naval version of the missile was also developed, based on the C version of the missile - the RIM-72C Sea Chaparral. This was not adopted by the U.S. Navy, however it was exported to Taiwan.
The Chaparral system is manually fired by visually tracking the targets, slewing the missile carrier into the general direction, and waiting for the missile seekers to "lock on" to the target. It is not suitable for engaging helicopters "popping up" behind cover, for instance.
In 1977 Ford and Texas Instruments started a project to give the Chaparral a limited all-weather capability through the addition of a FLIR camera. The test firings in 1978 also used a new smokeless motor, which greatly improved visibility after firing and made it much easier to fire follow-up rounds. The testing proved successful, and the FLIR upgrades were carried out in September 1984. Existing missiles were upgraded with the new motor to become the MIM-72E, while new-build versions (otherwise identical) were known as the MIM-72F.
A final upgrade adapted the greatly improved seeker from the FIM-92 Stinger to the MIM-72, starting in 1980. The Stinger's seeker is considerably more capable in terms of off-axis "sighting," as well as being able to reject most common forms of jamming. Ford was contracted to deliver the resulting MIM-72G starting in 1982, and all existing missiles had been updated by the late 1980s. New-build G models followed between 1990 and 1991. By this point in time the system was already being removed from regular Army service, and being handed over to the National Guard.
Two export-only versions of the MIM-72 were also built, the MIM-72H which is an export version of the MIM-72F, and the MIM-72J, a MIM-72G with a downgraded guidance and control section.
The missile cost approximately $80,000 and M48 fire units $1.5 million.
