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ATR 42 Surveillance Plane Crashes Into Indonesian Mountain

ATR 42 Surveillance Plane Crashes Into Indonesian Mountain

Fisheries monitoring flight ends in tragedy as turboprop strikes Mount Bulusaraung

Overview

An Indonesia Air Transport ATR 42-500, chartered by the government for fisheries surveillance, crashed into Mount Bulusaraung in South Sulawesi on January 17, 2026. Ten people were aboard—seven crew members and three Marine Affairs Ministry staff conducting aerial monitoring of Indonesian waters. Rescuers located the wreckage the following day, recovering one body from a ravine near the 1,353-meter peak.

Indonesia's National Transportation Safety Committee has classified this as controlled flight into terrain: the aircraft was flyable, the crew was in control, but they flew into a mountain they didn't see. The 25-year-old turboprop had been reconfigured for surveillance work just nine months earlier. Investigators will now determine whether the crew deviated from their approach path, whether fog obscured the terrain, or whether other factors contributed to Indonesia's latest CFIT accident.

Key Indicators

10
People aboard
Seven crew and three government passengers on fisheries surveillance mission
25
Aircraft age (years)
Built in 2000 for Air Dolomiti, converted to surveillance platform in April 2025
1,353m
Peak elevation
Mount Bulusaraung, where wreckage was found on steep karst terrain
20km
Distance from destination
Aircraft lost contact approximately 20 kilometers from Makassar airport

People Involved

Andy Dahananto
Andy Dahananto
Captain, ATR 42-500 PK-THT (Presumed deceased)
Farhan Gunawan
Farhan Gunawan
Co-Pilot, ATR 42-500 PK-THT (Presumed deceased)
Soerjanto Tjahjono
Soerjanto Tjahjono
Chairman, KNKT (Leading crash investigation)
MA
Muhammad Arif Anwar
Head, South Sulawesi Search and Rescue Agency (Coordinating recovery operations)

Organizations Involved

IN
Indonesia Air Transport
Charter airline
Status: Operator of crashed aircraft

Charter specialist serving oil, gas, mining, and government clients since 1968.

NA
National Transportation Safety Committee (KNKT)
Government investigation agency
Status: Leading crash investigation

Indonesia's independent transportation accident investigation body, reporting directly to the President.

DI
Directorate General of Marine and Fisheries Resources Surveillance (PSDKP)
Government surveillance agency
Status: Contracted the crashed aircraft

Indonesia's fisheries enforcement arm, operating aerial and maritime patrols against illegal fishing.

AT
ATR
Aircraft manufacturer
Status: Providing technical support to investigation

Franco-Italian manufacturer of regional turboprops, producing the ATR 42 and ATR 72.

Timeline

  1. Debris Spotted from Air

    Discovery

    Helicopter AI-7301 reports white debris above Bulusaraung Hill. Second helicopter confirms wreckage north of the peak.

  2. Wreckage Located

    Discovery

    Joint search team confirms crash site on steep slope of Mount Bulusaraung. Fuselage, tail section, engine, and scattered debris found. One body recovered from ravine 200 meters from peak.

  3. KNKT Announces Preliminary Finding

    Investigation

    KNKT Chairman Soerjanto Tjahjono classifies accident as controlled flight into terrain. Investigation formally opened with ATR providing technical support.

  4. Departure from Yogyakarta

    Flight

    ATR 42-500 PK-THT departs Adisutjipto International Airport for routine two-hour flight to Makassar with 10 aboard.

  5. Final Contact with ATC

    Flight

    Aircraft communicates with air traffic control approximately 20 kilometers from destination. Controllers observe plane not on correct approach path and issue instructions.

  6. Aircraft Lost

    Incident

    Contact lost. Local residents near Mount Bulusaraung report hearing explosion and seeing smoke in the Bantimurung-Bulusaraung National Park.

  7. Search Operations Begin

    Response

    BASARNAS deploys helicopters, drones, and ground teams. Fog, rain, and high winds hamper initial search efforts in mountainous terrain.

  8. Converted to Surveillance Platform

    Modification

    Reconfigured for aerial surveillance work. Contracted to Marine and Fisheries Resources Surveillance agency for maritime patrol missions.

  9. Transferred to Indonesia Air Transport

    Background

    Acquired by Indonesian charter operator, re-registered as PK-THT. Configured with 46-seat economy layout.

  10. Enters Service with Air Dolomiti

    Background

    Aircraft delivered to Italian regional carrier Air Dolomiti, operating European routes for nine years.

  11. Aircraft Manufactured

    Background

    ATR 42-512 serial number 611 built in Toulouse, France. Registered as I-ADLN for delivery to Air Dolomiti.

Scenarios

1

Navigation Error in Poor Visibility Confirmed

Discussed by: Aviation safety analysts, based on preliminary CFIT classification and reports of fog at crash site

Investigation determines crew deviated from correct approach path due to poor visibility, striking terrain they couldn't see. KNKT has already indicated the aircraft was not on the correct approach. Local residents reported thick fog and limited visibility. If confirmed, this would echo patterns from previous Indonesian CFIT accidents where weather and mountainous terrain combined with navigation errors.

2

Technical Malfunction Contributed to Crash

Discussed by: Aviation observers noting operator's statement about pre-flight maintenance issues

Indonesia Air Transport acknowledged the aircraft had "a problem with the engineering" that was fixed before departure. If investigators find the repair was inadequate or a separate system failure occurred—particularly affecting navigation or terrain awareness equipment—the focus shifts from crew actions to maintenance and airworthiness oversight. Black box data will be critical.

3

Crew Ignored Terrain Warnings

Discussed by: Analysts familiar with Indonesian CFIT history, particularly the 2012 Sukhoi crash pattern

Multiple previous Indonesian CFIT accidents involved crews disabling or ignoring terrain warning systems. The 2012 Sukhoi Superjet crash into Mount Salak occurred after pilots turned off functioning TAWS. If cockpit voice recorder analysis reveals the ATR crew dismissed or deactivated warnings, this would indicate systemic training deficiencies rather than isolated error.

4

Investigation Inconclusive Due to Recorder Damage

Discussed by: Flight safety researchers noting harsh crash conditions

Impact on steep mountainous terrain after controlled flight can damage flight data and cockpit voice recorders beyond recovery. If black boxes are destroyed or severely degraded, investigators may be unable to determine exact cause, similar to cases where only partial data was recoverable. The preliminary CFIT classification would stand without further explanation.

Historical Context

Trigana Air Flight 267 (2015)

August 2015

What Happened

An ATR 42-300 carrying 54 people crashed into Tangok Mountain in Papua while approaching Oksibil Airport. Captain Hasanuddin, with 25,200 flight hours, deviated from the standard visual approach path—a maneuver he had made routinely on previous flights. The flight data recorder was inoperative. No one survived.

Outcome

Short Term

Remains the deadliest ATR 42 accident in history. Investigation found no technical failure.

Long Term

KNKT determined crew habitually deviated from prescribed routes without assessing terrain risk. Aeronautical charts for Oksibil contained incorrect minimum safe altitude data. Prompted calls for upgraded navigation infrastructure in Papua.

Why It's Relevant Today

Identical CFIT pattern: experienced crew, turboprop aircraft, mountainous Indonesian terrain, deviation from correct approach. Demonstrates how normalized unsafe practices can persist until fatal.

Sukhoi Superjet 100 Mount Salak Crash (2012)

May 2012

What Happened

A Sukhoi Superjet 100 on a promotional demonstration flight from Jakarta crashed into Mount Salak, killing all 45 aboard including the aircraft's test pilot Alexander Yablontsev. The plane was showing off the new Russian-built jet to potential Indonesian airline customers.

Outcome

Short Term

Bodies and wreckage scattered across steep volcanic terrain. First accident involving the Superjet type.

Long Term

Investigation found the terrain warning system worked correctly and warned pilots 38 seconds before impact. Crew turned off warnings, believing they were malfunctioning, while distracted by conversations with passengers. Jakarta Post dubbed Mount Salak 'an airplane graveyard.'

Why It's Relevant Today

Demonstrates pattern of crews dismissing functional safety systems in Indonesian mountain-approach scenarios. Raises question of whether ATR crew similarly ignored or lacked effective terrain warnings.

Indonesia Aviation Safety Reforms (2007-2015)

2007-2015

What Happened

Following a series of fatal crashes and European Union bans on Indonesian carriers, Indonesia undertook comprehensive aviation safety reforms. KNKT was separated from the Ministry of Transportation in 2012 to ensure independent investigations. New oversight protocols were implemented.

Outcome

Short Term

EU lifted ban on Indonesian airlines in 2018 after safety improvements verified.

Long Term

Fatal accidents dropped from 27 in 2000-2009 to 18 in 2010-2019. However, CFIT and loss of control accidents continued, particularly on routes involving mountainous terrain and remote airports with limited navigation infrastructure.

Why It's Relevant Today

Context for Indonesia's ongoing safety challenges. Despite improvements, mountainous terrain, aging regional fleets, and limited ground-based navigation aids in remote areas continue to produce CFIT accidents.

10 Sources:
+4
Al Jazeera Bloomberg Tempo Simple Flying Airways Magazine Jakarta Globe South China Morning Post Aviation Safety Network Tempo Simple Flying