The RUM-139 VL-Asroc is a rocket designed and built by Lockheed Martin for the U.S. Navy.
Development of the weapon began in 1983 when Goodyear was commissioned by the U.S. Navy to develop a ship-launched anti-submarine missile compatible with the MK 41 Vertical Launch System . During development, Goodyear Aerospace was bought by Loral, whose defence devision was in turn purchased by Lockheed Martin in 1986.
The rocket is a RUR-5 Asroc with a replacement solid-fuel booster section and a digital guidance system. It carries a lightweight MK 46 MOD 5A homing torpedo which is dropped from the rocket at a precalculated point on its trajectory, parachuting to the water surface. From 1996 the torpedo was replaced by the newer RUM-139A and subsequently the RUM-139B .
The rocket became operational in 1993, with more than 450 in operation today. It is nearly 5 meters in length with a range of 28 kilometers and a speed of over mach 1.
