Marine One Anti-Missile Countermeasures
Irfrared countermeasures (IRCM) for presidential aircraft were installed in the mid 1980s as infrared-guided, heat-seeking anti-aircraft missiles became widespread. Three models of presidential helicopters show such IRCM devices: the two workhorses in regular use, the VH-3D Sea King and the newer VH-60D Blackhawk. The VH-3D has a pair of IRCM devices at the bottom, the VH-60D has IRCM devices at top and bottom. A third helicopter sometimes used, the VH-1N Iroquois, has a single device at the top. These appear to be AN/ALQ-144A units.
Sanders AN/ALQ-144 Infrared Countermeasures Set. Mounted above the tailpipe of an AH-1S Cobra attack helicopter, this ALQ-144 radiates modulated infrared light to jam the seekers of optically guided SAMs and AAMs. This compact 1200W DC/12.7 kg jammer is optimised for low/slow tactical aircraft with over 1300 sets installed on AH-1, AH-64, UH-1 and UH-60 helicopters. Note that this particular Cobra lacks the scabbed on optical detectors of the AVR-2 Laser Warning Receiver which is integrated with the AH-1's internal APR-39 Radar Warning Receiver.