WEEK 17
H2F brings you the ‘helicopter mayday of the week’ with a short accident report summary. I tell you what happened. You think more about why it happened. We all learn from it. Because that’s what accident reporting is for.
TITLE
High workload during rescue mission leads to wheels-up landing on beach.
WHAT?
A Japan Coast Guard Leonardo AW139 was dispatched on a search and rescue mission to recover survivors stranded in a small cove following the passage of a tropical storm. During the rescue, the crew successfully hoisted two survivors and elected to land on an adjacent beach to transfer them to personnel on the ground. The helicopter subsequently landed with the landing gear retracted.
WHERE?
Miyagi Prefecture, Japan.
WHEN?
9 August 2016. Japan Transport Safety Board (JTSB) published their investigation in 2018.
HOW?
While descending through about 150 ft to commence the hoist rescue, the aircraft generated an aural caution indicating that the landing gear remained retracted. The aircraft commander instructed the co-pilot to cancel the alert while simultaneously managing turbulence and monitoring torque to avoid exceeding engine limitations. After successfully completing the hoist recovery, the crew focused on hazards associated with the sloping ground landing and the risk of downwash lifting FOD on the beach during landing. In this high-workload environment, the pre-landing checklist was not completed and the landing gear position was not verified.
CONDITIONS?
The mission was conducted in a demanding SAR environment following a tropical storm. The helicopter encountered considerable turbulence and high power during the hoisting phase. The landing site was a sloping beach with potential debris hazards requiring close attention from the crew. Multiple tasks occurred in rapid succession, with each crew member focused on separate operational demands associated with the rescue: hoisting; aircraft handling; attending a casualty; and confined area hazards.
OUTCOME?
The helicopter sustained damage to the lower fuselage, antennas, hoist light cover, and searchlight assembly. No injuries occurred. Following extension of the landing gear, the aircraft was flown back to Sendai Airport. Subsequent safety actions by the Japan Coast Guard included renewed emphasis on CRM, checklist discipline, role allocation, briefings, safety audits, and dynamic risk assessment.
WHY?
The JTSB concluded that the helicopter was damaged because it landed with the landing gear retracted. Contributing factors included:
- High task load with multiple tasks occurring simultaneously within a short time period.
- High and sustained task and cognitive workload on the aircraft commander.
- Crew members concentrating on their own tasks, reducing cooperation, mutual support, and monitoring.
- Insufficient time for the captain to transition mentally from rescue activities to landing procedures, breaking down normal work cycles and routines.
- Failure to perform the pre-landing checklist required by the flight manual.
- Failure to verify landing gear position before touchdown.
REFERENCE?
Japan Transport Safety Board. (2018). Aircraft serious incident investigation report: AgustaWestland AW139 JA968A, Miyagi Prefecture, Japan, 9 August 2016. Japan Transport Safety Board.
Note:
Accident reports selected from the following open source databases: US NTSB; UK AAIB; Flight Safety Foundation’s Aviation Safety Network; Australia’s ATSB. Ireland’s AAIU; Taiwan’s TTSB; France’s BEA; Spain’s CIAIAC. Germany’s BFU.
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