A remote-controlled underwater vehicle is now helping divers search for the remains of victims and flight recorders from a Sriwijaya Air jet that crashed into the Indonesian sea three days ago shortly after take-off. The Boeing 737-500 plane with 62 people on board plunged into the Java Sea on Saturday afternoon, four minutes after taking off from Jakarta’s main airport. Indonesian police made the first identification of a victim from the crash on Monday. Flight attendant Okky Bisma was identified by his fingerprints, said a police official. “My super kind husband ... Heaven is your place ... Until we meet again darling,” Okky’s wife, who is also a flight attendant, wrote on her Instagram account. The Boeing 737-500 jet was headed on a domestic flight to Pontianak on Borneo island, about 740km from Jakarta, before it disappeared from radar screens. It was the second major air crash in Indonesia since 189 passengers and crew were killed in 2018 when a Lion Air Boeing 737 MAX also plunged into the Java Sea soon after taking off. The jet that crashed on Saturday is a different design. “Today we are focusing on finding the victims,” Yusuf Latif, a spokesman for search and rescue agency Basarnas, said on Tuesday. Divers have narrowed down an area where they believe the flight recorders, known as black boxes, are believed to be but search efforts have been hindered by debris, officials said. The remotely operated underwater vehicle has been deployed to help scour the seabed, while navy vessels with sonar search from the surface. Once the flight data and cockpit voice recorders are found, Indonesia’s National Transportation Safety Committee (KNKT) expects to be able to read the information in three days. With few immediate clues on what caused a catastrophic loss of control after take-off, investigators will rely heavily on the flight recorders to determine what went wrong. The Sriwijaya Air plane was nearly 27 years old, much older than Boeing’s problem-plagued 737 MAX model. Older 737 models are widely flown and do not have the stall-prevention system implicated in the MAX safety crisis. Starting with just one plane in 2003, Sriwijaya Air has become Indonesia’s number 3 airline group, aided by its strategy of acquiring old planes at cheap prices and serving routes neglected by competitors. The mid-market airline, which has few international flights was launched by brothers Chandra and Hendry Lie, whose family was involved in tin mining and the garment industry, and their business partners 17 years ago. Their single plane flew from their home town of Pangkal Pinang on Bangka Island to Indonesia's capital Jakarta. Its focus on second and third-tier routes gave it a loyal customer base and helped it snare nearly 10 per cent market share behind Lion Air and national carrier Garuda Indonesia. "They had a reasonable business approach," an industry source who was not authorised to speak publicly said of Sriwijaya's founders. "They are not flamboyant people like many you see running airlines." They used a conservative business model of acquiring older planes on the cheap rather than taking advantage of low-cost financing to purchase large fleets of new aircraft like other fast-growing carriers such as Lion Air, Malaysia's AirAsia Group Bhd and Vietnam's VietJet Aviation JSC. The fleet of Sriwijaya and regional offshoot NAM Air is nearly 20 years old on average – nearly three times older than Lion Air group, according to website Planespotters.net. The plane involved in the crash, a 737-500, was one of only 77 remaining in service globally, aviation data provider Cirium said. Other current operators including the likes of Nigeria's Air Peace and Kazakhstan's SCAT Airlines. Two former Sriwijaya employees told Reuters there were strategic reasons for keeping such an old model in service beyond the cheaper acquisition cost. The smaller seating capacity of 120 was more appropriate for certain routes like Jakarta to Pontianak on Borneo flown by the plane that crashed on Saturday and the 737-500 could land at airports that were otherwise served by turboprops due to short runway lengths, they said on condition of anonymity. Sriwijaya did not respond immediately to a request for comment. Older jets can be operated just as safely as newer ones if maintained properly, though the cost of doing so is higher, as are the operating costs because they are less fuel-efficient. Rising upkeep costs and low fare prices due to heated competition meant that by 2018 Sriwijaya had accrued large debts owed to Garuda's maintenance arm, GMF AeroAsia. As of September 30, 2020, Sriwijaya and NAM owed around $63 million in unpaid bills to GMF AeroAsia and Garuda had warned of impairment losses on $37.5 million owed by Sriwijaya as part of a failed co-operation agreement, according to GMF AeroAsia and Garuda. The status of its financial position since the start of the pandemic is unclear, but a Sriwijaya pilot, speaking on condition of anonymity, said there were salary cuts and a reduction in the number of planes operating during the pandemic, in line with many other airlines globally. The pilot added the airline had been complying with all training and maintenance requirements throughout the pandemic. Sriwijaya and NAM together have 34 planes for operations and half of them are in service, according to Planespotters.net. "The question now is whether Sriwijaya, already in poor financial health, is able to overcome this accident as Covid-19 has crippled all airlines," said Shukor Yusof, head of Malaysian aviation consultancy Endau Analytics.