815 Naval Air Squadron is a squadron of the Fleet Air Arm, part of the Royal Navy. The squadron is currently based at RNAS Yeovilton (HMS Heron) in Somerset, United Kingdom and it is the Navy's front line Lynx Naval Air Squadron. It currently comprises about 25 Westland Lynx Hunter / Maritime Attack (HMA) Mk8 helicopters. It is the largest helicopter squadron in western Europe.