The Indonesian Navy has detected the tail of AirAsia plane QZ8501 at a depth of 29m (100ft) in the Java Sea.
"We managed to detect the tail of the aircraft using the side-scan sonar" said Colonel Yayan Sofyan, commander of the warship Bung Tomo.
Rescue teams have also recovered a total of 30 bodies from the ocean – some believed to still be strapped to their seats on-board the doomed plane.
Four people have been identified so far, all of whom were Indonesian: Grayson Herbert Linaksita, Kevin Alexander Soetjipto, AirAsia stewardess Khairunnisa Haidar Fauzie, and Hayati Lutfiah Hamid.
It is believed the flight got into difficulty after trying to climb to 36,000ft to avoid bad weather.
"Its speed had dropped by about 200km/hr, which was not enough speed to sustain flight," Geoffrey Thomas, editor-in-chief of FlightRatings.com, told Channel NewsAsia.
The Airbus A320 disappeared with 162 people on board while flying from Surabaya in Indonesia to Singapore.