Investigation Summary
The approach to Surabaya was conducted in challenging environmental conditions, including a thunderstorm and rain with visibility of 8,000 meters and winds from 240 degrees at 7 knots. The approach to Runway 28 was characterized by significant instability below 200 feet. Data from the flight recorders indicated that the aircraft's vertical speed occasionally exceeded 2,500 feet per minute during the final descent, far beyond standard stabilized approach criteria. Shortly before touchdown, control of the aircraft was transferred from the co-pilot to the Pilot in Command (PIC). During this critical phase, the Ground Proximity Warning System (GPWS) issued 'Sink Rate' and 'Pull Up' alerts, which the crew did not respond to. Upon touchdown, the aircraft struck the runway with a vertical force of 5g, causing the fuselage to fracture and buckle severely aft of passenger seat row 16. The right main landing gear initially touched down approximately 4 meters outside the runway edge. Two passengers sustained minor injuries during the evacuation. This accident occurred just weeks after the fatal crash of Adam Air Flight 574 (PK-KKW) into the Makassar Strait; unlike that event, Flight 172 involved a structural failure on landing with no loss of life. In a controversial move following the accident, Adam Air personnel repainted the aircraft white overnight, covering the airline's orange livery before the National Transportation Safety Committee (NTSC) had completed its initial on-site investigation. The airline denied this was an attempt to hide evidence, claiming it was standard procedure for handling damaged aircraft.
Final Conclusions
The NTSC final report concluded that the accident was caused by an excessive sink rate during touchdown following an unstabilized approach. The investigation found no evidence of technical malfunctions prior to the landing. Contributing factors included the flight crew's failure to adhere to sterile cockpit procedures, as they were engaged in non-flight-related conversation regarding company fuel policy and training programs until 2,000 feet. Crucially, the crew failed to perform an approach briefing or read the required checklists. Furthermore, the crew did not respond to multiple GPWS 'Sink Rate' and 'Pull Up' warnings issued during the final descent.
Photographic Evidence (1)
Video Analysis
No video analysis linked for this case file yet.
Airframe & Maintenance
Systems & Failure Modes
Fuselage Structure
The Boeing 737-300 fuselage suffered a catastrophic structural failure (fracture) due to the 5g vertical load during the hard landing.
Flight Data Recorder (FDR)
The FDR provided critical data showing the excessive sink rate and vertical acceleration during the final approach and touchdown.
Interesting Facts
- 01The aircraft initially touched down with the right main gear 4 meters outside the runway edge.
- 02Vertical acceleration at touchdown was measured at 5g.
- 03The approach was unstable below 200 feet with vertical speeds exceeding 2,500 feet per minute.
- 04The aircraft was manufactured in 1994 and had accumulated 37,936 flight hours.
- 05Adam Air repainted the aircraft to cover its livery before the NTSC investigation was complete.
Safety Actions & Advisories
Aircraft Age Restrictions
Following the accident, the Indonesian government announced plans to ban commercial jets over 10 years of age and eventually proposed banning operations of aircraft over 30 years old.
Airline Safety Ranking System
Indonesia introduced a three-tier ranking system for airlines based on safety records, where level-three ratings could lead to an airline being shut down.
Known Controversies & Unanswered Questions
Post-Accident Repainting
Reference ↗Adam Air repainted the aircraft white overnight before investigators finished their work, leading to allegations of evidence tampering, which the airline denied.