What is a towed-array sonar and its advantage?

• A. It is deployed on the hull to improve stability
• B. It is deployed behind the vessel to reduce self-noise and extend detection range
• C. It uses air to detect surface objects
• D. It provides faster propulsion

Answer: (B)

A towed-array sonar is a long line of hydrophones that is pulled behind a vessel. The main advantage is that it sits away from the ship’s hull and machinery, which greatly reduces self-noise and wake interference. This quiet listening environment lets the array detect fainter underwater sounds and hear at longer ranges, especially at the low frequencies that quiet submarines are most detectable in. Meanwhile, being towed and deeper also improves directional sensing and target localization. The other options don’t describe how a sonar system works: detecting with air would be wrong for sonar, and propulsion has nothing to do with sensing.