Aviation Safety Council releases Investigation Report of Sunrise Airlines helicopter a BK-117 registration B-77088, which crashed into sea offshore of Kinmen Shang Yi Airport.

On July 10, 2009, a Sunrise Airlines helicopter BK-117 registration B-77088, was on its return from Taipei Song Shan Airport to Kinmen Shang Yi Airport after conducting an Emergency Medical Service flight. Two Flight crews and one medical technician were on board. The aircraft crashed into sea one nautical mile south of Shang Yi Airport. The pilot in command survived from the crash, while the first officer and the medical technician were found dead; the aircraft was destroyed.

ASC launched investigation according to the Aviation Occurrence Act, and invited CAA and Sunrise Airlines for joint investigation. Investigation Report is published after approval by the ASC council members on Feb. 22, 2011, at 142th council meeting.

Findings related to probable causes: The aircraft was operated by two flight crews； however the first officer fell asleep during the approach phase, and failed to monitor the instruments and to make standard callouts to the PIC in regard to heading deviation, altitude low, and excessive vertical speed. During the visual approach, affected by scattered clouds and outside lighting, the PIC did not continuously maintain his visual reference and therefore gave excessive control input on attitude correction. Coupled with the inertia due to leveling off from steep descent, the aircraft as a result descended below the expected altitude and crashed into sea. The PIC might suffer from black hole effect, which led to the aircraft’s  steep descent profile. The PIC did not realize the altitude was too low until crash into sea.

Findings related to the risks are as follow: Complacency of the PIC, lack of the awareness of the risks of CFIT(Controlled Flight Into Terrain) and Visual Illusion. The PIC allowed the first officer to take a rest and continued the flight as a single crew operation but did not maintain the approach track. He changed the planned circling approach to a direct landing on the helipad without approach light guidance.  The approach took place at the time when the Circadian Rhythm was at the lowest and the noise and vibration of the helicopter aggravated the effect of fatigue. Sunrise Airlines is responsible for not properly re-schedule the flight crew duty, taking the fatigue level of flight crew into consideration and increasing the risk of fatigue as a result. In addition, training in regard to CFIT, night vision limitation, visual illusion, fatigue management still leave room for improvements. CAA should also take into consideration of operation characteristics and review technical guide and related regulation concerning Helicopter Emergency Medical Service.

Aviation Safety Council issued a total of 15 Safety Recommendations. 9 recommendations to Sunrise Airlines: Reinforce training and risk evaluation with respect to CFIT, night vision, visual illusion, fatigue management. Review HEMS flight crew dispatch regulation, and distinguish between standby time and rest time. Revision and management of Flight Operation and related manuals should make sure manuals are complete, correct, consistent, and convenient. Consider installation of GPWS or similar system on helicopters to warn pilots for terrain closure. 5 recommendations to Civil Aeronautics Administration: Reinforce supervision of HEMS operators and ensure proper flight crew dispatch, risk evaluation, operational manual revision and management, and training regarding CFIT/Night flight/Fatigue Management and Emergency Escape. For the purpose of increase flight safety of HEMS, review and update domestic HEMS regulation and technical guide by referring to international HEMS investigation report, research, regulation, and technical guide. One recommendation to Department of Health, Executive Yuan: Call CAA, HEMS operators, and academic or research organizations to establish a platform of communication, coordination, and cooperation on HEMS flight safety issues. Provide operators equipments, strategies, and management tools that exceed the requirement of regulations and improve flight safety for future operations.

Full investigation report is available for download at http://www.asc.gov.tw

Sherry Liu, Engineer
Tel: 89127388-330  
Email:sherry@asc.gov.tw