Accident Boeing 737-347 (SF) PK-YSY,

ASN Wikibase Occurrence # 320020

Date:	Tuesday 13 September 2016
Time:	07:33
Type:	Boeing 737-347 (SF)
Owner/operator:	Trigana Air Service
Registration:	PK-YSY
MSN:	23597/1287
Year of manufacture:	1986
Total airframe hrs:	59420 hours
Cycles:	48637 flights
Engine model:	CFMI CFM56-3B1
Fatalities:	Fatalities: 0 / Occupants: 3
Aircraft damage:	Substantial, written off
Category:	Accident
Location:	Wamena Airport (WMX) - Indonesia
Phase:	Landing
Nature:	Cargo
Departure airport:	Jayapura-Sentani Airport (DJJ/WAJJ)
Destination airport:	Wamena Airport (WMX/WAJW)
Investigating agency:	NTSC
Confidence Rating:	Accident investigation report completed and information captured

Narrative:
A Boeing 737-300 cargo plane operated by Trigana Air Service as flight 7321 sustained substantial damage in a landing accident on runway 15 at Wamena, Papua, Indonesia.
TGN7321 was a scheduled cargo flight from Jayapura-Sentani Airport to Wamena Airport. On board the aircraft were two pilots and one Flight Operation Officer (FOO) as a loadmaster. The aircraft carried 14,913 kg of cargo.
The aircraft cruised at an altitude of 18,000 feet and prior to descent, the pilot observed that the Visual Meteorological Conditions (VMC) existed. The pilots able to identify the other Trigana flight from Sentani to Wamena in front of them.
The aircraft made an orbit at X-POINT which located at 8 NM from runway 15 in order to allow a preceding flight to land.
At approximately 7,000 feet altitude, the pilot received landing clearance from the Wamena Tower controller. At this position, the pilot could not identify his visual checkpoints and decided to reduce the rate of descent and continued the approach.
At approximately 5,700 feet altitude at about 2 NM from the runway threshold, the pilot was able to see the runway and increased the rate of descent. Just prior to touchdown the aircraft rolled left 28° and pitched down 11°, before returning to approximately wings level and +7° pitch. The aircraft then touched down with a vertical acceleration of 3.25 g.
Both main landings gear subsequently collapsed and the left main landing gear completely detached during landing. The aircraft stopped at approximately 1,890 meters from the beginning of runway 15.

This was the second Boeing 737-300F landing accident at Wamena in just over a year. On August 28, 2015, a Cardig Air aircraft touched down about 35 meters before the beginning of runway 15, causing the left hand main gear to collapse.

Contributing Factors: "Refer to the previous aircraft that was landed safely, the pilot confidence that a safe landing could be made and disregarding several conditions required for go around."

Accident investigation: