Gunship Academy
by Richard Sheffield
Countermeasures
To survive in the modern battle environment, an aircraft needs to be more than tough; it must have the technology currently available to confuse the enemy weapons and make them miss. The Apache contains state-of-the-art countermeasures equipment.
Enemy weapons systems are aimed in one of four ways: They are aimed optically, they are aimed with radar, they are laser-guided, or they are heat-seeking (infrared). There is not much you can do to confuse visually aimed or laser-guided weapons other than flying low or at night.
The Apache is fitted with a system to alert the crew that they're being illuminated by a laser. Once they know that they're being targeted, they can react and try to break the lock. Radar and infrared systems can be fooled with the proper technology.
For radar-guided weapons, the Apache contains the APR-39 radar warning receiver. This receiver alerts the crew to radar operating in the area. The system displays the direction from which the radar signal is coming on a small CRT screen. If the crew realizes that the radar has locked onto them, they can use the ALQ-136 radar jammer to analyze the radar signal and generate the necessary jamming response. Metal chaff designed to produce a large radar reflecting cloud can also be used.
Heat-seeking weapons are confused by the ALQ-144 IR jammer. It creates a changing source of infrared energy designed to create errors in the guidance system. M-206 IR flares can also be dropped to lure the weapon away from the aircraft. The engine exhaust ports were designed to disperse the heat as widely as possible to decrease the intensity of the Apache's heat or IR signature.
Figure 2-4. Apache Attack Helicopters in Service at Ft. Hood, Texas.A flight of five Apaches involved in a training exercise at Ft. Hood, Texas.
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