The Sriwijaya Air plane which crashed into the Java Sea on Saturday had passed an airworthiness inspection last month, officials have said.
The 26-year-old Boeing 737, grounded for nine months last year, resumed commercial flights on 22 December.
The aircraft with 62 people on board was still functioning and intact before it crashed, preliminary results showed. There were no survivors.
One of Flight SJ182’s two black boxes has now been retrieved.
On Tuesday, Air Chief Marshal Hadi Tjahjanto told reporters that the flight data recorder had been brought ashore, but his team was still looking for the cockpit voice recorder.
The authorities hope the black boxes can provide vital information about the possible cause of the crash.
The plane was en route from the capital Jakarta to the city of Pontianak on Borneo island when it crashed just minutes after take-off on Saturday.
Indonesian police earlier identified the first victim – Okky Bisma, a 29-year-old flight attendant on the plane.
Indonesia’s transport ministry on Tuesday said the aircraft had been grounded during the pandemic, and passed an inspection on 14 December.
It made its first flight five days later with no passengers, then resumed commercial flights shortly after that.
Separately, the National Transportation Safety Committee (KNKT) said that preliminary findings showed that the plane had reached the height of 10,900ft (3.3km) at 14:36 local time on Saturday (07:36 GMT), then made a steep drop to 250ft at 14:40, before it stopped transmitting data.
KNKT head Soerjanto Tjahjono added that the plane’s turbine disc with a damaged fan blade had been found – ruling out the theory that the plane had exploded mid-air.
“The damaged fan blade indicates that the machine was still functioning when it crashed. This [is] also in line with the belief that the plane’s system was still functioning when it reached 250ft,” said Mr Soerjanto in a written statement to reporters.
What progress has been made so far?
Search teams are continuing to comb the waters at the crash site, trying to retrieve the cockpit voice recorder.
Earlier on Tuesday, the KNKT said a device used to locate the black boxes had experienced “technical problems or equipment damage”.
Authorities added that they were waiting for a new “ping locator” to arrive from Singapore.
Several pieces of debris, body parts, wreckage and passengers’ clothing have already been recovered.
According to news wire AFP, there were some 2,600 personnel involved in the search operation yesterday, along with more than 50 ships and 13 aircraft.
Investigators are already analysing items which they believe to be a wheel and part of the plane’s fuselage. A turbine from one of its engines is also among the debris that has been recovered.
Transport safety officials say they are currently in the second stage of a five-stage investigation process. This stage consists of compiling and collecting data and could take up to a year to wrap up.
What happened to the aircraft?
The Sriwijaya Air passenger plane departed from Jakarta’s main airport at 14:36 local time (07:36 GMT) on Saturday.
Minutes later, at 14:40, the last contact with the Boeing 737 plane was recorded, according to the transport ministry.
The usual flight time to Pontianak, in West Kalimantan province in the west of the island of Borneo, is 90 minutes.
There were thought to be 50 passengers – including seven children and three babies – and 12 crew on board, though the plane has a capacity of 130. Everyone on board was Indonesian, officials say.
Witnesses said they had seen and heard at least one explosion.
Sriwijaya Air, founded in 2003, is a local budget airline which flies to Indonesian and other South-east Asian destinations.
The missing aircraft is not a 737 Max, the Boeing model that was grounded from March 2019 until last December following two deadly crashes.