Helicopter Sikorsky RH-53D Serial 65-364 Register 158691 used by US Navy USN. Aircraft history and location Aircraft History 158691 US Navy 1991-11-17USNw/o 17nov91 HM-19 /NW-621 HM-19 crashed in mountains during a routine training flight one year after I retired from HM-19...I was part of this BUNOs crew! HM-19 Send Updates Use APP to upload photo @ (optional) When Now? / / Send