Northrop Grumman Guardian

The Northrop Grumman Guardian is a passive anti-missile countermeasure system designed specifically to protect commercial airliners from shoulder-launched missiles (commonly known as MANPADS), using directed infrared countermeasures (DIRCM) technology.

According to the Wall Street Journal, the program is now the subject of a lawsuit alleging that "in 2007 and 2008 the company intentionally inflated costs, presented false bills, lied about progress and withheld test data from the Department of Homeland Security."

The extensive proliferation of MANPADS has resulted in many being available to non-state groups on the international arms black market, sometimes for as little as US$5,000 each. This has resulted in a marked increase of MANPADS attacks on commercial airliners, including the failed 2002 Mombasa airliner attack, the 2003 Baghdad DHL attempted shootdown incident and the 2007 Mogadishu TransAVIAexport Airlines Il-76 crash. According to the U.S. State Department, over 40 civilian aircraft have been hit with MANPADS since 1970, with about 400 passengers and crewmembers killed. Of these, six were airliners.

In 2003, Senator Barbara Boxer (CA-D) and Congressman Steve Israel (NY-D) introduced legislation in both the House and Senate (H.R. 580/S. 311 The Commercial Airline Missile Defense Act) that directed the Department of Homeland Security (DHS) to sponsor a research and development program that would result in a missile defense system that could be installed on commercial airliners; the bill also authorized funding for the program.

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Wikipedia