A multinational team searching for a crashed AirAsia passenger jet found another large underwater object believed to be part of the plane, but persistent bad weather hampered efforts on Sunday to locate its black box recorders and recover bodies of victims.

Indonesian officials say five pieces of wreckage have now been pinpointed on the sea floor off Borneo, where the Airbus A320-200 crashed a week ago with 162 people on board.

Divers were sent to investigate the debris early on Sunday, but diving had since been suspended due to bad weather, the head of Indonesia's search and rescue agency, Fransiskus Bambang Soelistyo, said.

Flight QZ8501 crashed into the Java Sea last Sunday, about 40 minutes after taking off from Indonesia's second largest city Surabaya en route for Singapore. There were no survivors.

Earlier Rukman Soleh, weather bureau chief in Pangkalan Bun, the southern Borneo town where the search operation is based, had said there could be a break later on Sunday in the wind and heavy seas that have dogged recovery efforts all week.

"Weather should provide the search effort with a window of opportunity today, with lower waves expected for the next two days," he said.

Speaking at the same morning briefing for pilots, Air Force Lt Col Johnson Supriadi said efforts would be divided between recovering bodies and locating wreckage and the all-important cockpit voice and flight data recorders.

Until investigators can examine the recorders the cause of the crash remains unknown, but the area is known for intense seasonal storms and BMKG, Indonesia's meteorological agency, has said bad weather was likely a factor.

"The flight document provided by the BMKG office shows fairly worrying weather conditions for the aircraft at cruising level on the chosen route," the agency said in a report.

A source close to the investigation told Reuters that radar data appeared to show the aircraft made an "unbelievably" steep climb before it crashed, possibly pushing it beyond the A320's limits.

The Indonesian captain, a former air force fighter pilot, had 6,100 flying hours on the A320 and the plane last underwent maintenance in mid-November, according to Indonesia AirAsia, 49 percent owned by Malaysia-based AirAsia.

SHALLOW WATER

The objects that are the main focus of the search were located by ships about 90 nautical miles off the coast of Central Kalimantan province, on the island of Borneo. The largest object is around 18 metres long.

The suspected wreckage is lying in water around 30 metres (100 ft) deep, which experts say should make it relatively straightforward to recover if the rough weather abates.

Efforts to capture images with remote operated vehicles (ROVs) were frustrated on Saturday by poor visibility.

Thirty-one bodies of the mostly Indonesian passengers and crew have so far been recovered, including some still strapped in their seats. Many more may be still trapped in the fuselage of the aircraft.

The crash was the first fatal accident suffered by the AirAsia budget group, whose Indonesian affiliate flies from at least 15 destinations across the sprawling archipelago.

The airline has come under pressure from Indonesian authorities, who have suspended its Surabaya to Singapore operations saying the carrier only had a licence to fly the route on Mondays, Tuesdays, Thursdays and Saturdays.

Indonesia AirAsia said it would co-operate with the transport ministry whilst it investigates the licence.

A joint statement from Singapore's civil aviation authority (CAAS) and Changi Airport Group said that AirAsia had the necessary approvals to operate a daily flight between Surabaya and Singapore. – Reuters