by means of self-contained, automatically controlling devices that respond to inertial forces. IR Infrared. iron bomb A simple bomb consisting of a metallic casing filled with high explosive. Any of the Mk series of bombs. IRST Infrared Search and Track. island The portion of an aircraft carrier's superstructure above the flight deck. jamming The act of confusing enemy radar systems with radio frequency noise. jet propulsion A propelling force that moves an airplane forward in reaction to the momentum of gases accelerating out the rear of the engine. kill circle The aiming reticle for an A-A missile. knot Abbreviation for nautical mile or 1.15 statute miles. kts Knots. LANTIRN Low-Altitude Navigation Targeting Infrared