Authorities have been unable to detect a "rescue signal" from the emergency locator transmitter (ELT) on board the Ground Self-Defense Forces helicopter that disappeared in Okinawa Prefecture on Thursday, defense ministry sources said.
ELTs transmit location information automatically when aircraft experience strong impacts or flooding, the sources said.
According to the GSDF, the ELT aboard the GSDF UH-60JA multipurpose helicopter was installed behind the cockpit. Crews are trained to turn on ELTs before aircraft take off.
