An AirAsia plane that crashed into the Java Sea last month with 162 people on board had climbed at a speed that was higher than normal and then stalled, Indonesia's transport minister said Tuesday.

"In the final minutes, the plane climbed at a speed which was beyond normal," said Transport Minister Ignasius Jonan, citing radar data.

"The plane suddenly went up at a speed above the normal limit that it was able to climb to. Then it stalled," he told reporters.

Flight QZ8501 crashed on December 28 in stormy weather, during what was supposed to be a short trip from the Indonesian city of Surabaya to Singapore.

Search and rescue teams have recovered the plane's black boxes -- the cockpit voice recorder and flight data recorder -- and are analysing them.

Crash investigators have ruled out terrorism as a cause for the crash, and are focusing on possible human error or problems with the aircraft.

Divers have so far recovered just 53 bodies.