The U.S. Marine Corps, as they often do, are adopting some gear that the U.S. Army has recently bought and used successfully. This time it's a new system to protect aircraft from heat seeking missiles. CMWS (Common Missile Warning Systems), although developed by the army, is intended (as the name implies) to be used by the other services. But the other services are not forced to use the CMWS, they have the option to. Thus the army has to get everyone's requirements taken care of. This is not an easy task, but a "common" system is a cheaper one (economies of scale), and saves money for all users. So far, the army has 600 CMWS systems installed (at a cost of about half a million dollars each), and will eventually get over 2,500. The CMWS has been in development and production for over a decade, and is meant to be easily upgraded (via reprogramming of software, or swapping in new components.) Basically, the CMWS is four or more heat sensors mounted on an aircraft, and a computer that takes the sensor data and decides which detected heat is actually an approaching missile. If a missile is detected, a flare is launched, to draw the missile away from the aircraft. An alternative defense is a laser, which delivers a dose of distracting heat to the missiles heat detector.