PANGKALAN BUN (INDONESIA) — The search and recovery effort for AirAsia flight QZ8501 has turned up its most significant discovery yet — one that raised hopes of recovering the “black boxes” that could shed light on what caused the plane to meet its fateful end in the Java Sea.

Indonesia’s search and rescue agency (Basarnas) yesterday found the plane’s tail more than 30m underwater, about 30km from the suspected site of the crash. Measuring about 10m, the tail was discovered by an underwater machine using a sonar scan and identified by divers who spotted the letters AXT on the fuselage, which form part of the PK-AXT code painted on the aircraft. The flight data recorders of an aircraft are usually located in the tail.

The Singapore-bound flight, carrying 162 people on board, vanished from radar screens after leaving Surabaya on Dec 28.

While bodies of the passengers and debris have been retrieved over the past few days — one body was taken to Pangkalan Bun yesterday, bringing the count to 40 — rain, strong waves and poor visibility underwater due to sediment kicked up by strong currents have hampered efforts below the surface.

At a press conference in Jakarta, Basarnas chief Bambang Soelistyo showed photographs of what is believed to be the tail of the plane, adding that the team “is still desperately trying to locate the black box”.

Minutes after the news broke, AirAsia chief executive officer Tony Fernandes tweeted: “I am led to believe the tail section has been found. If (it is the) right part of tail section, then the black box should be there ... We need to find all parts soon, so we can find all our guests to ease the pain of our families. That still is our priority.”

Divers equipped with cameras were swimming in waters of 2m to 3m of visibility when they saw the tail on the seabed, partly buried in mud, Basarnas director of operations Suyadi Bambang Supriyandi told reporters at Pangkalan Bun, the centre of search operations.

Weak signals coming from the tail were detected, but vanished when divers got closer, he said.

Coordinating Maritime Affairs Minister Indroyono Soesilo said six ships are currently within a two-square-nautical-mile area near the location of the tail.

Subsurface vehicles will be used to retrieve wreckage and bodies which may still be strapped to their seats, he added. Mr Supriyandi said divers may also be sent to search for the black box.

While lifting the wreckage out of the mud will be a challenge, Mr Indroyono said subsurface vehicles will be able to lift objects weighing up to 250 tonnes.

The required equipment, located in Batam, can be brought here in about 24 hours, he said.

The tail of the plane was discovered after international search teams slashed an underwater search area from 600 square nautical miles on Tuesday to only 300 square nautical miles yesterday. The number of ships searching this area was also increased from five to eight.

Indonesia National Transportation Safety Committee (KNKT) investigator Nurcahyo Utomo told TODAY that debris found on the seabed provided more information about the crash as compared with floating debris, which will drift far from the crash site.

“Because if it is on the seabed, it would not have moved much from the time of the impact to the time it was found,” he said.

Search and rescue personnel retrieving the wreckage can help explain the context in which the debris was found to investigators, he said.

Mr Supriyandi cautioned that the tail section of the aircraft may not be fully intact. “The location of the tail is relatively far from the point of last contact, about 30km,” he said.

“The black box is located behind the door, to the right side of the tail. There is a possibility that the tail and the back of the plane are broken up.”

Meanwhile, the Disaster Victim Identification Police Department Republic of Indonesia announced that it had identified eight more bodies of the passengers, bringing the total number of bodies identified to 24. WITH AGENCIES