WEEK 6
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
Rear passenger door separates in flight.
WHAT?
An air medical helicopter was conducting a positioning flight with a pilot and two medical crew-members onboard. Before departure, a crew nurse slid closed and latched the left rear door. About five minutes into cruise flight, the door opened and then separated from the helicopter.
WHERE?
Shoals, West Virginia, during a flight from Cabell Huntington Hospital Heliport, West Virginia, toward a hospital helipad in Louisa, Kentucky.
WHEN?
The incident occurred on January 29, 2016, at about 13:03 local time. The NTSB final report was published on March 18, 2019.
HOW?
During cruise flight at approximately 125 knots, the pilot heard increased wind noise and realized the left rear sliding door had opened. The pilot instructed the nurse to attempt to close the door, but moments later the door separated from the airframe. The door had likely been incorrectly locked before takeoff. The helicopter was flying well above the manufacturer’s maximum allowable speed for operation with the door open (80KIAS), which contributed to the door’s separation. Post-incident examinations found no pre-existing damage or mechanical failures in the door mechanism.
CONDITIONS?
The helicopter was operating in cruise configuration at about 125 knots, whereas the flight manual specified lower never-exceed speeds for operation of the door (70KIAS) or flight with the rear door open (80KIAS).
OUTCOME?
The helicopter diverted to a nearby airport and no injuries occurred. The aircraft sustained substantial damage from the door as it departed in flight, including a rotor blade punctured from the leading edge to the trailing edge, and impact damage to the transmission hatch. The detached door was later recovered and examined.
WHY?
- Improper locking of the rear passenger door by the specialty nurse.
- Door opening in flight due to incorrect operation rather than mechanical failure.
- Aircraft operating above the allowable speed for flight with the door open or unlatched.
- Door separation resulting from aerodynamic loads once the door opened at cruise speed.
- The report gives very limited detail on contributing human-factors causes. For example, it does not identify or discuss:
- Workload or time pressure
- Training deficiencies or unfamiliarity with the door system
- SOP or checklist issues
- CRM or communication failures
- Fatigue, distraction, or situational awareness problems
- Organisational or cultural factors
- Design confusion or ergonomic factors affecting the latch
REFERENCE?
National Transportation Safety Board. (2019, March 18). Aviation investigation final report: Accident number ERA16LA098 (Eurocopter France EC130 B4, N133HN). National Transportation Safety Board. https://data.ntsb.gov/Docket?ProjectID=92658
https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/92658/pdf
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.
competentaviators.com 