Sriwijaya Air aircraft that crashed into the sea off the coast of Jakarta, Indonesia had passed an airworthiness inspection last month, officials said.
Flight SJ182 was grounded between March and December last year, resumed commercial flights on 22 December.
Preliminary findings also showed the aircraft was still functioning and intact before it crashed.
The plane had 62 people on board when it plunged into the Java Sea. The cause for this remains unknown.
Indonesia’s Transport Ministry on Tuesday said the Boeing 737 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.
‘Rule out explosion theory mid-air’
Separately, the National Transportation Safety Committee (KNKT) said that preliminary findings showed the aircraft reached the height of 10,900 feet at 14:36 local time on Saturday, then made a steep drop to 250 feet 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 exploded mid-air.
“The damaged fan blade indicates that the machine was still functioning when it crashed. This also in line with the belief that the plane’s system was still functioning when it reached 250ft,” said Mr Soerjanto said.
The jet involved was nearly 27-year-old Boeing 737-500 was much older than Boeing’s problem-plagued 737 MAX model, one of which crashed off Jakarta in late 2018, killing all 189 people aboard the Lion Air flight. Older 737 models are widely flown and do not have the system implicated in the MAX safety crisis.
The Boeing 737 is the world’s most-sold family of aircraft and has undergone several makeovers since it entered service in 1968.