The U.S. Navy has ordered seven units of a new towed array sonar system. The TB-37 MFTA (multi-function towed array) cost $3.9 million each. The MFTA is built to be quickly and easily installed in most surface warships. Towed array sonars are let loose from the rear of the ship and remains connected via a cable (handling data, power and keeping it attached to the ship). The towed array is kept far enough behind the ship to avoid the loud noise a surface ship produces at sea. The towed array is also equipped so that it can be lowered to the optimum depth for listening or broadcasting (like radar.) Modern towed array systems can be used at higher ship speeds, and can be deployed, and recovered, in rougher seas (up to Sea State 6).
Towed array sonar is much more effective than sonar that is built into a ship, but takes up a lot of space on a ship. With MFTA ASW (Anti-Submarine Warfare) capabilities can quickly (in a few weeks) be increased by installing MFTA on ships that do not have it and assigning a dozen or so sailors to handle MFTA operation. All this provides sonar operators and commanders with much more useful data on submerged subs near the MFTA equipped ships.