If he had turned back, things may have been different when the same jet took off and crashed on its next flight hours later, killing all 189 passengers on board.

The incident happened on a flight from Bali to Jakarta. But when the technical problems seemed to resolve, the flight continued.

The same Boeing 737 MAX jet then took off at 6.20am the next morning, bound for Bangka island, off Sumatra, and plunged into the sea 13 minutes later. Just before the crash, the pilot had made a request to return to base.

Herson, chief of the airport authority for the Bali-Nusa Tenggara area, told Reuters that after the initial call during the first flight on Sunday, the pilot updated the control tower to say that the plane was flying normally and he would not return to the airport as requested.

“The captain himself was confident enough to fly to Jakarta from Denpasar,” said Herson, who goes by one name, speaking by phone from Bali.

While the captain may have been confident, Lion Air has remained tight-lipped about the alert on the earlier flight, citing the ongoing crash investigation.

The pilot of another plane that was approaching Bali just after the Lion Air jet took off said he was ordered to circle above the airport and listened in to a radio conversation between the Lion Air pilot and air traffic controllers.

“Because of the Pan-Pan call, we were told to hold off, circling the airport in the air,” said the pilot, who declined to be named.

“The Lion plane requested to return back to Bali five minutes after takeoff, but then the pilot said the problem had been resolved and he was going to go ahead to Jakarta.”

Pilots use Pan-Pan calls to flag urgent situations. They are a step down from Mayday, which signals severe distress.

The Denpasar-Jakarta flight landed at the Indonesian capital’s airport at 10.55pm local time on Sunday.

A Lion Air spokesman declined to comment when asked about the distress call on the earlier flight, citing the ongoing crash investigation.

The budget airline’s chief executive Edward Sirait said earlier this week that a technical problem had occurred on the Denpasar-Jakarta flight but it had been resolved “according to procedure”.

The aircraft flew erratically and its airspeed readings were unreliable, according to an accident investigator.

According to data from flight tracking website FlightRadar24, the jet displayed unusual variations in altitude and airspeed in the first several minutes of flight — including a 267-metre drop over 27 seconds when it would normally be ascending — before stabilising and flying on to Jakarta.

Two passengers on the Sunday Bali-bound flight interviewed on Indonesian TV recalled unsettling details such as a strange engine sound, a smell of burnt cables, and panicked passengers crying out for God to save them as the plane rapidly lost altitude.

Indonesia’s second-deadliest air disaster since 1997 has prompted renewed concern about its patchy safety record, and the government has said Lion Air will be regulated more closely.

BLACK BOX RECOVERED

Authorities say they will immediately begin examining a damaged black box that has finally been retrieved from the sunken wreckage.

The investigation into the first ever crash of a Boeing Co 737 MAX aircraft, introduced into commercial service last year, will also be scrutinised by the global aviation industry.

“Tonight we will move as quickly as possible to download what is in this black box,” deputy chief of Indonesia’s transportation safety committee (KNKT) Haryo Satmiko told a news conference on Thursday.

The extent of damage to the device showed the “extraordinary impact” of the crash, he said.

Despite initial reports, authorities did not know for certain whether the “crash survivable memory unit” was from the flight data recorder or cockpit voice recorder, as portions of it were missing, Satmiko said.

Searchers have yet to detect a location signal from the second of the two black boxes, housed at opposite ends of the aircraft.

Although the sea floor is only about 30 metres down, strong currents and energy pipelines in the area have hampered search efforts.

A navy diver on board a search vessel told the broadcaster Metro TV that his team found the orange cylinder containing the recorder among debris on the muddy sea floor.

Under normal conditions, the data should only take two hours to download, said Satmiko, although analysing it could take several weeks.

The results from a preliminary investigation will be made public after 30 days, another KNKT official said.

FADING HOPE FOR VICTIMS’ FAMILIES

Hopes are fading of finding a large section of fuselage intact, with easily retrievable bodies inside.

“What is important for us is to get more information about the victims because having their remains back is important for us so we can bury them properly,” said Ade Inyo, whose brother-in-law was on the flight.

Only one of the flight’s passengers has been identified from the partial remains retrieved so far.

The investigation will be carried out with help from Boeing, General Electric and the US Federal Aviation Administration, officials have said.

The National Transportation Safety Committee (NTSC) said it would examine the black box to get a clearer picture of what happened on the flight from Bali on Sunday, in addition to the flight that crashed on Monday.

It will also focus on four Lion Air staff, including its technical director, who the transport ministry said it has suspended on Wednesday, amid speculation that the aircraft had not been airworthy.

Lion Air said the aircraft that crashed had been airworthy and the pilot and co-pilot had 11,000 hours of flying time between them.