Helicopter Sikorsky MH-60S Seahawk Serial Register 166304 used by US Navy USN. Aircraft history and location Aircraft History 166304 US Navy 2012HSC-2 /HU-721 HSC-2 2021-04 HSC-26 Det 1 /HU-721 HSC-26 Send Updates Use APP to upload photo @ (optional) When Now? / / Send