 The Joint Tactical Information Distribution System (JTIDS)/Link 16 for data communications was added later on.The F-14 also features electronic countermeasures (ECM) and radar warning receiver (RWR) systems, chaff/flare dispensers, fighter-to-fighter data link, and a precise inertial navigation system.The early navigation system was inertial-based; point-of-origin coordinates were programmed into a navigation computer and gyroscopes would track the aircraft's every motion to calculate distance and direction from that starting point.