Crash of a De Havilland DHC-6 Twin Otter 300 in Bilogai: 3 killed

Date & Time: Sep 15, 2021 at 0737 LT
Operator:
Registration:
PK-OTW
Flight Type:
Survivors:
No
Site:
Schedule:
Nabire – Bilogai
MSN:
493
YOM:
1976
Country:
Region:
Crew on board:
3
Crew fatalities:
Pax on board:
0
Pax fatalities:
Other fatalities:
Total fatalities:
3
Circumstances:
The twin engine aircraft departed Nabire Airport at 0640LT on a cargo flight to Bilogai, carrying three crew members and a load of building materials. On approach to Bilogai-Sugapa Airport, the crew encountered poor visibility due to foggy conditions when the aircraft impacted trees and crashed on the slope of a mountain. The wreckage was found about three hours later at an altitude of 2,400 metres some 3,4 km west of the airfield. The aircraft was totally destroyed and all three occupants were killed.

Crash of a Cessna 208B Grand Caravan in Bilogai-Sugapa: 1 killed

Date & Time: Nov 23, 2011 at 0942 LT
Type of aircraft:
Operator:
Registration:
PK-VVG
Flight Type:
Survivors:
Yes
Schedule:
Nabire - Bilogai-Sugapa
MSN:
208B-1308
YOM:
2007
Country:
Region:
Crew on board:
2
Crew fatalities:
Pax on board:
0
Pax fatalities:
Other fatalities:
Total fatalities:
1
Captain / Total flying hours:
1859
Captain / Total hours on type:
1550.00
Copilot / Total flying hours:
690
Copilot / Total hours on type:
231
Aircraft flight hours:
4331
Aircraft flight cycles:
5375
Circumstances:
The flight route was Nabire to Bilogai as an unscheduled cargo flight. There were two pilots on board and the freight load was a mixture of food, palm oil, and cement. The aircraft departed from Nabire at 2355 UTC (0855 LT), the estimate time of arrival of Bilogai was 0045 UTC. At 0042 UTC the aircraft was reported above touchdown zone and the altitude recorded of 6,960 feet, direction 277 degrees and air speed 94 knots. The aircraft executed a go around due to an unauthorized person entering the shoulder of the runway 27, the aircraft then continued to climb and headed left. It was reported while the aircraft initially was climbing with the nose up but following lost altitude. During go around manoeuvre the aircraft attitude was in high nose up position, caused the angle of attack was too high and beyond a stall margins caused the aircraft stall. The aircraft bank to the right and crashed on a corn farm at coordinate S 03 44.58 E 137 0.96 and altitude about 6,550 feet with heading about 260 degrees. The aircraft was destroyed on impact with the ground. The captain seriously injured and still on seat in the aircraft wearing the shoulder harness. The second in command was fatally injured outside of the aircraft at the crashed site.
Probable cause:
FINDINGS :
• The aircraft was airworthy prior the accident and there was no evidence of system malfunction during the flight.
• The crew had valid license and medical certificate.
• There were no fences at the airport perimeter.
• There was a local plantation area nearby the runway.
• Unauthorized person entering the shoulder of the runway 27.
• There was no warning signal to alert if unauthorized persons entering the runway, especially during any aircraft Takeoff and Landing.
• The valley (gap) on the south side of the runway was too narrow for successful go around manoeuvre by a caravan aircraft.
• The aircraft most probably stalled due to very high angle of attack, when the aircraft was manoeuvre to avoid the surrounding terrain and bank to the right.
• The communication of incoming and outgoing Susi Air aircraft from and to Bilogai was only to Susi Air ground handling Agent at Sugapa.
CAUSES :
The aircraft was executed a Go Around due to a unauthorized person entering the shoulder of the runway 27, after go around, crew tried to avoid terrain impact, increasing the aircraft attitude more pitching up caused the angle of attack was higher and beyond a stall margins , finally stall just before impact.
Final Report: