Jakarta, Indonesia (CNN) Searchers have now recovered both so-called black boxes from AirAsia Flight QZ8501 and may have located the fuselage of the plane, an Indonesian official said Tuesday, adding more pieces to help solve the puzzle of what caused the disaster.

The fuselage, or main body, of the plane is believed to have been found by a ship scanning for wreckage northeast of where the tail section was previously discovered, said Supriyadi, an operations coordinator at Indonesia's national search and rescue agency who goes by only one name.

But he said he hasn't seen the full report on the reported discovery yet -- and it hasn't been confirmed so far by the head of the search and rescue agency.

The discovery of the fuselage would be a significant development as officials have suggested that many of the bodies of those on board the plane are likely to be found with it.

Forty-eight bodies have so far been recovered from the sea, some of them still strapped into seats. But more than 100 remain missing.

The overwhelming majority of the people on Flight QZ8501 were Indonesian. There were also citizens of Britain, France, Malaysia, Singapore and South Korea.

Black boxes contain the what and the why

On Tuesday, divers retrieved the cockpit voice recorder, which is designed to retain all sounds on a plane's flight deck.

The device is expected to help investigators understand what went wrong aboard Flight QZ8501, which went down in the Java Sea last month with 162 people aboard as it was headed toward Singapore from the Indonesian city of Surabaya.

On Monday, searchers recovered the plane's other key information source, the flight data recorder , which stores a vast amount of information about the aircraft's performance, including air speed and cabin pressure.

The flight data recorder tells investigators what happened on a plane, but the cockpit voice recorder tells them why, said Mardjono Siswosuwarno, a senior official at Indonesia's National Transportation Safety Committee, which is leading the investigation into the disaster.

"The why is mostly in there," he said of the voice recorder, which captures conversations between pilots as well as other sounds in the cockpit.

Analysis of data to take months

The two flight recorders have been taken to a lab in Jakarta, the Indonesian capital, for analysis.

Investigators say they have successfully downloaded the contents of both devices. But Mardjono cautioned that interpreting the information requires much more time.

After the download, investigators should have "a pretty good idea within a couple of days" of what happened aboard the plane, Mary Schiavo, a former inspector general of the U.S. Department of Transportation, said this week.

The flight data recorder usually contains hundreds of parameters and thousands of data points, she said, that look a bit like an electrocardiogram when they're printed.

Photos: The search for AirAsia Flight QZ8501 Photos: The search for AirAsia Flight QZ8501 Crews remove the fuselage of AirAsia Flight QZ8501 from a vessel at the Tanjung Priok Port in Jakarta, Indonesia, on Monday, March 2. AirAsia Flight QZ8501 was en route from Surabaya, Indonesia, to Singapore when it lost contact with air traffic control on December 28. There were 162 people on board. Hide Caption 1 of 47 Photos: The search for AirAsia Flight QZ8501 The fuselage is lifted from the Java Sea during the recovery mission on March 2. Hide Caption 2 of 47 Photos: The search for AirAsia Flight QZ8501 Indonesian search and rescue personnel unload recovered bodies at the Kumai seaport on Sunday, February 8. Hide Caption 3 of 47 Photos: The search for AirAsia Flight QZ8501 Workers load the tail of the plane onto a truck February 7 at the Kumai seaport. Hide Caption 4 of 47 Photos: The search for AirAsia Flight QZ8501 Crew members inspect body bags on the deck of a ship in the Java Sea on Friday, January 23. Hide Caption 5 of 47 Photos: The search for AirAsia Flight QZ8501 A police officer stands guard near pieces of the plane's wreckage at a warehouse in Pangkalan Bun, Indonesia, on Monday, January 19. Hide Caption 6 of 47 Photos: The search for AirAsia Flight QZ8501 This photo, taken by a remotely operated underwater vehicle and released Wednesday, January 14, by Singapore's Defense Ministry, shows part of the plane's fuselage lying on the floor of the Java Sea. Hide Caption 7 of 47 Photos: The search for AirAsia Flight QZ8501 Indonesian officials remove the cockpit voice recorder from AirAsia Flight QZ8501 on Tuesday, January 13. Indonesian divers retrieved it from beneath the wreckage of the plane. Hide Caption 8 of 47 Photos: The search for AirAsia Flight QZ8501 A flight data recorder was retrieved from the Java Sea on Monday, January 12. Hide Caption 9 of 47 Photos: The search for AirAsia Flight QZ8501 An Indonesian worker cuts part of the plane's tail January 12 after debris from the crash was retrieved from the Java Sea. Hide Caption 10 of 47 Photos: The search for AirAsia Flight QZ8501 A portion of the plane's tail section is seen on the deck of a rescue ship after it was recovered from the Java Sea on Saturday, January 10. Hide Caption 11 of 47 Photos: The search for AirAsia Flight QZ8501 An Indonesian rescue helicopter flies during search operations in the Java Sea on Friday, January 9. Hide Caption 12 of 47 Photos: The search for AirAsia Flight QZ8501 Search personnel unload the body of a victim upon arriving at the airport in Pangkalan Bun on January 9. Hide Caption 13 of 47 Photos: The search for AirAsia Flight QZ8501 Members of the Indonesian Search and Rescue Agency carry pieces of the jet in Pangkalan Bun on January 9. Hide Caption 14 of 47 Photos: The search for AirAsia Flight QZ8501 There was a major breakthrough in the search for the wreckage on Wednesday, January 7. Indonesian search and rescue officials released an image of the plane's tail section as seen on the floor of the Java Sea. Hide Caption 15 of 47 Photos: The search for AirAsia Flight QZ8501 Writing could be made out, showing the AirAsia insignia and other identifying features. The find is important because the plane's flight recorders were located in the tail section. Hide Caption 16 of 47 Photos: The search for AirAsia Flight QZ8501 Divers were sent to take images of the section after metal detectors identified large objects in the water where officials were searching for the lost plane. Hide Caption 17 of 47 Photos: The search for AirAsia Flight QZ8501 Search and rescue personnel carry seats from the flight on Monday, January 5. Hide Caption 18 of 47 Photos: The search for AirAsia Flight QZ8501 An Indonesian navy member holds a piece of window panel that was recovered during search operations. Hide Caption 19 of 47 Photos: The search for AirAsia Flight QZ8501 Crew members in an Indonesian air force helicopter look out of the windows over the Java Sea during a search operation on Sunday, January 4. Hide Caption 20 of 47 Photos: The search for AirAsia Flight QZ8501 Members of an Indonesian search and rescue team carry items recovered from the search area in Pangkalan Bun on January 4. Hide Caption 21 of 47 Photos: The search for AirAsia Flight QZ8501 Members of the Mawar Sharon Church attend a prayer service for the relatives of lost loved ones January 4 in Surabaya, Indonesia. Hide Caption 22 of 47 Photos: The search for AirAsia Flight QZ8501 Indonesian navy officers coordinate the recovery of bodies taken to the vessel KRI Banda Aceh during recovery operations on Saturday, January 3. Hide Caption 23 of 47 Photos: The search for AirAsia Flight QZ8501 Members of the Indonesian navy return to the vessel with remains recovered from the crash area. Hide Caption 24 of 47 Photos: The search for AirAsia Flight QZ8501 Recovered victims are placed on the deck of the Indonesian ship on January 3. Hide Caption 25 of 47 Photos: The search for AirAsia Flight QZ8501 Members of an Indonesian search team carry a coffin at Iskandar Air Base on Friday, January 2. Hide Caption 26 of 47 Photos: The search for AirAsia Flight QZ8501 Relatives and friends grieve as they attend a ceremony January 2 in Surabaya. Hide Caption 27 of 47 Photos: The search for AirAsia Flight QZ8501 A member of the Indonesian Red Cross prepares coffins at a hospital in Pangkalan Bun on January 2. Hide Caption 28 of 47 Photos: The search for AirAsia Flight QZ8501 Members of the National Search and Rescue Agency and Indonesian soldiers carry coffins containing bodies of victims in Pangkalan Bun on January 2. Hide Caption 29 of 47 Photos: The search for AirAsia Flight QZ8501 This photograph released by the Singapore Defense Ministry shows the front and back of a piece of debris that resembles an aircraft window panel. Hide Caption 30 of 47 Photos: The search for AirAsia Flight QZ8501 Members of a search and rescue team carry the body of a victim in Pangkalan Bun on Thursday, January 1. Hide Caption 31 of 47 Photos: The search for AirAsia Flight QZ8501 Marine divers prepare their gear on the deck of a ship before searching for passengers and debris January 1 at Kumai port in Pangkalan Bun. Hide Caption 32 of 47 Photos: The search for AirAsia Flight QZ8501 Indonesian soldiers carry a victim's coffin upon arrival at an air force base in Surabaya on Wednesday, December 31. Hide Caption 33 of 47 Photos: The search for AirAsia Flight QZ8501 Indonesian soldiers carry coffins of crash victims on December 31. Hide Caption 34 of 47 Photos: The search for AirAsia Flight QZ8501 Relatives of passengers pray together inside a holding room at Juanda International Airport in Surabaya on December 31. Hide Caption 35 of 47 Photos: The search for AirAsia Flight QZ8501 Indonesian air force personnel show debris, including a suitcase, that was found floating near the site where the AirAsia flight disappeared. Hide Caption 36 of 47 Photos: The search for AirAsia Flight QZ8501 Debris floats in the Java Sea on December 30. Hide Caption 37 of 47 Photos: The search for AirAsia Flight QZ8501 A member of the Indonesian navy monitors a radar screen during a search operation over the waters near Bangka Island, Indonesia, on December 30. Hide Caption 38 of 47 Photos: The search for AirAsia Flight QZ8501 Family members of missing passengers react at an airport in Surabaya after watching news reports on December 30. Hide Caption 39 of 47 Photos: The search for AirAsia Flight QZ8501 Debris floats in the Java Sea on December 30. Hide Caption 40 of 47 Photos: The search for AirAsia Flight QZ8501 Relatives of missing passengers comfort each other December 30 at Juanda International Airport in Surabaya. Hide Caption 41 of 47 Photos: The search for AirAsia Flight QZ8501 Relatives gather at Juanda International Airport as they wait for news on December 30. Hide Caption 42 of 47 Photos: The search for AirAsia Flight QZ8501 An Indonesian military airman looks out the window of an airplane during a search over the waters of Karimata Strait on Monday, December 29. Hide Caption 43 of 47 Photos: The search for AirAsia Flight QZ8501 Members of Indonesia's Marine Police pray before a search operation on December 29. Hide Caption 44 of 47 Photos: The search for AirAsia Flight QZ8501 Military personnel perform a search operation on Sunday, December 28. Hide Caption 45 of 47 Photos: The search for AirAsia Flight QZ8501 Sunu Widyatmoko, CEO of Indonesia AirAsia, gives a press conference in Surabaya announcing that the flight lost contact with air traffic control. Hide Caption 46 of 47 Photos: The search for AirAsia Flight QZ8501 An official from Indonesia's national search and rescue agency points to the position where AirAsia Flight QZ8501 went missing. Hide Caption 47 of 47

Mardjono said he expected a preliminary report to be released within a month of the crash, which happened December 28.

But it's unclear how much information the initial document will contain beyond what's already been made public. The final report containing investigators' full conclusions will take months, Mardjono said.

The agency's final report into Adam Air Flight 574 -- which crashed in Indonesian waters on New Year's Day 2007, killing all 102 people on board -- came out more than a year after that disaster.

Mardjono said the AirAsia plane's flight data recorder was in good condition after being pulled out of the water from under the debris of a wing Monday.

Did plane break apart on impact?

The recovery of the flight recorders took place after the plane's tail was lifted from the waves Saturday.

Observers have suggested that the locations of the different parts of debris indicate the plane broke apart when it hit the water, not when it was still at a high altitude.

Supriyadi, the Indonesian search official, said Monday that the debris patterns suggest the aircraft "exploded" on impact.

But the country's transportation investigators said it was premature to say what had happened, and one expert questioned the search official's choice of words.

"The word 'exploded' I think maybe loses a little bit in translation," said David Soucie, a former Federal Aviation Administration safety inspector. "I think really what he's meaning is a rupture from the impact itself.

"As with any hollow object hitting something very hard, the pressure differential between the outside and the inside is very significant, and it'll actually tear apart the aircraft on the top," Soucie said. "That may be what he's referring to."