About five AN/ALQ-204 Matador infrared (IR) countermeasures devices are located at the tail and behind the four engines, Previously used on the VC-137C (Boeing 707-320B) presidential aircraft and on airliners and executive aircraft, the device emits pulsed IR signals to foil attacks by heat-seeking missiles.
No matter where in the world the President travels, if he flies in an Air Force jet, the plane is called Air Force One. Technically, Air Force One is the call sign of any Air Force aircraft carrying the President. In practice, however, Air Force One is used to refer to one of two highly customized Boeing 747-200B series aircraft, which carry the tail codes 28000 and 29000. The Air Force designation for the aircraft is VC-25A
originally posted by: JIMC5499
I was browsing the net and found a picture of Obama boarding AF1. There is nothing remarkable in that, but the item on the engine pylon is interesting. There is a small fairing right below the wing that has what looks like three flat lenses. I'm thinking that this is part of AF1's defensive counter measures against a heat seeking missile. If anybody knows anything about this that is NOT CLASSIFIED, I'd appreciate them sharing the information.