May 29, 2012:
The U.S. Air Force has begun production of an upgraded missile warning system for its helicopters and aircraft. The NexGen Infrared missile warning system has longer detection range and fewer false alarms.
The warning system is one of two components in the DIRCM (Directional Infrared Countermeasures) that protects aircraft and helicopters from shoulder fired surface-to-air missiles. Most of these systems are shifting from flares to those that use lasers, to disrupt the missile heat seeker and force it to miss the target.
A typical DIRCM system has two components. First, there are four ultraviolet detection sensors (weighing about 2 kg/4.4 pounds each) mounted on different parts of the aircraft to detect an approaching missile. These sensors are linked to a 3-5 kg (6.6-11 pound) computer that contains software for determining that the object is indeed a missile and where it is headed. The detection computer is hooked to a countermeasures system using either flares and chaff (strips of metal foil) or a laser, to confuse the missiles guidance system (that is homing in on the heat of the aircraft, particularly the engines). The countermeasures component weighs 13-22 kg (30-50 pounds), depending on type or model.
Complete countermeasures systems cost about two million dollars each. Laser equipped ones are about 20 percent more expensive than those using flares, although that price differential is rapidly shrinking. So far, fewer than twenty American and NATO helicopters have been hit by missiles in Iraq and Afghanistan, and many more attempts have been foiled by missile countermeasures.