Divers have retrieved the crashed AirAsia plane's second black box from the bottom of the Java Sea, giving investigators the essential tools they need to start piecing together what brought Flight 8501 down.
Transportation Ministry official Tonny Budiono says the trapped cockpit voice recorder was freed from beneath the wing's heavy ruins early Tuesday from a depth of about 30 meters (100 feet), a day after the aircraft's flight data recorder was recovered.
It will be flown to the capital, Jakarta, to be downloaded and analyzed with the other box. Since it records in a two-hour loop, all discussions between the captain and co-pilot during the 42-minute journey should be available.
The two instruments, which emit signals from their beacons, are vital to understanding what brought Flight 8501 down on Dec. 28, killing all 162 people on board. They should provide essential information about the plane and all of the conversations between the captain and co-pilot for the duration of the flight.
Search and rescue workers used balloons and other equipment Tuesday to lift debris from the AirAsia plane wreckage to allow divers to retrieve the cockpit voice recorder, the search coordinator said.
The voice recorder takes audio feeds from four microphones within the cockpit and records all the conversations between the pilots, air traffic controllers as well as any noises heard in the cockpit, including possible alarms or explosions.
"There's like 200-plus parameters they record," said aviation safety expert John Goglia, a former U.S. National Transportation Safety Board member. "It's going to provide us an ocean of material."
The flight data recorder captures 25 hours' worth of information on the position and condition of almost every major part in a plane. It includes a multitude of data, including altitude, airspeed, direction, engine thrust, the rate of ascent or descent and what angle up or down the plane was pointed.
Supriyadi also said that an Indonesian warship had found pieces of the plane's windows and interior cupboards near the Java port of Semarang, about 720 kilometers (450 miles) southeast of where the jet had lost contact with Indonesian air traffic control, showing how far some debris has drifted over the 17 days since the accident.
The pilots of the AirAsia jet last had contact with air traffic controllers less than halfway into their two-hour flight from Surabaya, Indonesia's second-largest city, to Singapore. Saying they were entering a stormy area, they asked to climb from 32,000 feet (9,750 meters) to 38,000 feet (11,580 meters) to avoid threatening clouds, but were denied permission because of heavy air traffic. Four minutes later, the plane dropped off the radar. No distress signal was sent.
Searchers also have been trying to locate the main section of the plane's cabin, where many of the victims' corpses are believed to be entombed.
So far, only 48 bodies have been recovered. Decomposition is making identification more difficult for desperate families waiting to bury their loved ones. Nearly all of the passengers were Indonesian.
"I still believe many victims remain trapped there, and we must find them," said Gen. Moeldoko, Indonesia's military chief, who uses one name.