Trigana Air Flight 267 was a scheduled passenger flight from Sentani to Oksibil in the eastern Indonesian province of Papua. On 16 August 2015, the ATR 42 turboprop operating the service crashed on approach in the Bintang highlands region of Oksibil, killing all 49 passengers and 5 crew members. With 54 deaths, it is the deadliest accident involving the ATR 42, and the airline's deadliest accident since its establishment in 1991. The Indonesian National Transportation Safety Committee published its final report into the accident in December 2017. Deviation from visual approach guidance and visual flight rules without regard to weather and terrain, and the likely deactivation of the EGPWS system contributed directly to the crash, compounded by shortcomings in Trigana Air's safety culture.
== Background ==
=== Aircraft === The aircraft involved, was an ATR 42-300 registered as PK-YRN with serial number 102 and was powered by two Pratt & Whitney Canada PW120 engines manufactured in 1988 and was acquired by Trigana in 2005. Aircraft operated by Trigana Air were involved in fourteen accidents between 1992 and 2016, eleven of which resulted in hull loss.
=== Passengers and crew === The aircraft was carrying 49 passengers and 5 crew members. The passenger manifest released by Trigana Air indicated all on board were Indonesian. There were 44 adults, 3 children and 2 infants among the passengers. There were two pilots; Captain Hasanuddin (aged 60) had joined Trigana in 2000, he had 25,200 hours of total flying experience and 7,300 hours' experience flying ATR 42s. First Officer Ariadin Falani (aged 44) had joined Trigana in 2008 and had a total of 3,800 hours flying experience, of which 2,600 were in flying ATR 42s. Among the passengers were four postal servicemen heading to Oksibil to distribute the Indonesia Sejahtera card, a programme for the poor that President Joko Widodo developed and promoted while campaigning for the 2014 Indonesia Presidential Election. They were reportedly carrying around 6.5 billion rupiah ($US470,000). Three local government officials and two members of the Regional Representatives Council were also on board to attend celebrations in Oksibil for the 70th anniversary of Indonesia's independence.
== Accident ==
=== Flight ===
The Trigana Air flight took off from Sentani Airport in Jayapura at 14:22 WIT (UTC+9, 05:22 UTC) and was expected to land in Oksibil at about 15:04. Oksibil is a remote town near the country's border with Papua New Guinea. Oksibil Airport did not have an instrument landing system to guide aircraft in to land because it is located close to a mountain. Contact was lost with the aircraft at about 14:55. No distress call was made by the crew. The crew had been expected to make contact with ground staff at Oksibil Airport at around 15:00; attempts by those at the airport to contact the aircraft were unsuccessful. At the time of the accident, the aircraft was on the final section of its scheduled route.
=== Weather conditions === Conflicting statements regarding the weather conditions were released. Stormy weather was initially cited as a possible cause of the crash; however, it was later confirmed that the weather was good. Minister of Transportation Ignasius Jonan stated that bad weather was not the cause of the crash. Data from the local Indonesian Agency for Meteorology, Climatology and Geophysics office showed that the weather at the time of the crash was sunny. The crew of another aircraft landing prior to the crash also reported conditions at the time as "good". The Ministry of Transportation acknowledged that Indonesia's air navigation system equipment was very old, dating back to the 1950s, especially in remote areas such as Papua. Most airports in Papua did not have modern navigation aids at the time. Without this equipment, the airports and flight crew must rely on visual flight rules.
=== Search === At 15:30, Indonesia's National Search and Rescue Agency…