[Read more on what we know about the Indonesian plane crash.]

BANGKOK – When the coronavirus pandemic cleared Indonesia’s skies from air traffic, Capt. Afwan, an experienced Boeing 737 pilot for Sriwijaya Air.

A former Indonesian Air Force pilot who was widely admired and has over 30 years of flight experience, he filled his time with flight simulator sessions in Sriwijaya to ensure pilots were completing the minimum flying hours to keep their licenses. Like many in his Muslim-majority nation, he prayed regularly and advised colleagues to maintain their piety too.

On Saturday, the Sriwijaya Air Flight 182 under the direction of Captain Afwan crashed into the Java Sea a few minutes after take-off in heavy rain. The Boeing 737-500 series passenger jet carried 62 people, including six active crew members.

By Sunday afternoon, divers in waters northwest of the Indonesian capital Jakarta had retrieved objects from the aircraft: pieces of fuselage, aircraft wheels and soaked children’s clothing. Ten children and babies had been on board the flight, en route from Jakarta to Pontianak on Borneo Island, about a 90-minute journey.

Indonesian authorities appeared to be expecting no survivors, a dismal start to the year in a sprawling archipelago, with barely a year going by without a major aircraft accident. With the Indonesian aviation sector growing rapidly, safety and operational standards have not kept pace, industry insiders said.

“On behalf of the government and the entire Indonesian people, I would like to express my deep sorrow over this tragedy,” said Indonesian President Joko Widodo on Sunday.

The cause of the crash, after the aircraft lost more than 10,000 feet in altitude in a minute, is not yet known.

Indonesian investigators say they have confirmed the location of the plane’s data recorders at the water crash site, an area known as the Thousand Islands, and hope to find the so-called black boxes again soon. It may take months for investigators to figure out what terrible alchemy of weather, aircraft maintenance, and flight crew decision-making may have contributed to the deadly episode.

Nurcahyo Utomo, an investigator with Indonesia’s National Road Safety Committee, said the relatively narrow radius of debris, as seen in video footage, tentatively suggests that the plane may have broken apart upon hitting the water rather than exploding in midair.

However, there is no question that the skies of Indonesia remain among the most dangerous in the world, infested with a history of poor safety regulations that haunted domestic airlines for years. And the pandemic has gone through complicated efforts to restore its reputation and finances.

Due to a collapse in passenger traffic caused by the coronavirus, pilots said it was a struggle to maintain their professional edge even if their airlines offered simulator training. Sriwijaya has two flight simulators for older 737 models, pilots said.

Captain Rama Noya, the chairman of the Indonesian Pilots Association, who is also a pilot for Sriwijaya, said when he flew after a month-long hiatus, he felt he was “being reconnected”.

Updated

Jan. 11, 2021, 6:46 ET

The rusty feeling isn’t limited to pilots for Indonesian airlines.

“This is a problem for all countries right now,” said Gerry Soejatman, an Indonesian aviation expert.

For Indonesian airlines, which operate at wafer-thin profit margins, the decline in passenger traffic during the pandemic is particularly sharp. Sriwijaya Air was founded in 2003 during a boom in Indonesian aviation and was already in debt before the pandemic broke out. An earlier deal to revive his fortune by linking it with another airline group failed, even though Sriwijaya had never suffered a crash that resulted in death on board.

“Crew morale is low due to wage cuts caused by the pandemic, and crew performance concerns may be justified with low monthly hours,” Soejatman said.

Prior to the pandemic, Indonesian pilots, especially those with low-cost airlines like Lion Air, said they had been pressured to fly planes they considered unsafe. Complaints about overload and underpayment were widespread, as were allegations that oversight of regulators had decreased to get planes in the air.

A string of fatal plane crashes in Indonesia prompted European regulators to ban the country’s airlines for years. In 1997, 234 people died when a flight operated by the national airline Garuda crashed near the city of Medan. In 2014, 162 people died when an AirAsia flight from the city of Surabaya to Singapore crashed into the Java Sea.

And in 2018, a Lion Air 737 Max plunged into the Java Sea after a malfunction of its Boeing-designed anti-crystallization system. Months later, another 737 Max crashed in Ethiopia, which was equipped with the same antistall software, which resulted in the entire Max fleet worldwide being discontinued by the end of last year.

The plane in Sriwijaya, which crashed on Saturday, was neither a Max nor equipped with the problematic anti-stall software.

Pilots who knew Captain Afwan (54), who is known by one name like many Indonesians, said he was not a daredevil. His nephew Mohammad Akbar said he had flown for more than three decades.

“Captain Afwan was a very experienced pilot,” said Koko Indra Perdana, a Lion Air pilot who previously flew with Sriwijaya. “I believe in his abilities.”

The model that Captain Afwan flown, the 737-500 series, is considered a time-tested workhorse with no apparent systemic flaws. Still, the jet that crashed on Saturday was 26 years old, an age that requires regular maintenance to keep the plane in prime flight shape, aviation analysts said. And monsoon rains had delayed the flight on Saturday.

Sriwijaya only flew about a quarter of its fleet during the pandemic, industry insiders said. Regulators have warned that some of Boeing’s 737 models may need to be checked for possible air valve corrosion if they are not flown weekly.

“We don’t know the condition of the planes after months of landing,” said Captain Koko.

Mr Mohammad, the nephew of Captain Afwan, said his family had not received definitive news of the fate of the flight. He described his uncle as his “role model” who “always smiled”.

Captain Afwan had been accompanied in the cockpit by co-pilot Diego Mamahit, who, according to his LinkedIn profile, had worked as the chief first officer for Sriwijaya for almost six years. (The airline has not released any public details about the flight crew or the aircraft, other than that the Boeing jet was in “good condition”.)

“I really love to fly and enjoy my duties of operating Boeing 737 aircraft on all domestic routes in Indonesia,” Mamahit wrote on LinkedIn. “I have also seen many beautiful cities and breathtaking views on many Indonesian islands.”