AIRBUS HELICOPTERS INC AS350B3EAIR METHODS CORP
Frisco, CO, USA · 2015-07-03·N390LG
What happened
NTSB summary, verbatimThe NTSB's full report is available at http://www.ntsb.gov/investigations/AccidentReports/Pages/AccidentReports.aspx. The Aircraft Accident Report number is NTSB/AAR-17/01. On July 3, 2015, about 1339 mountain daylight time, an Airbus Helicopters AS350 B3e helicopter, N390LG, registered to and operated by Air Methods Corporation, lifted off from the Summit Medical Center Heliport, Frisco, Colorado, and then crashed into a parking lot; the impact point was located 360 feet southwest of the ground-based helipad. The pilot was fatally injured, and the two flight nurses were seriously injured. The helicopter was destroyed by impact forces and a postcrash fire. The flight was conducted under the provisions of 14 Code of Federal Regulations Part 135 on a company flight plan. Visual meteorological conditions prevailed at the time of the accident.
Probable cause
the Board's determinationAirbus Helicopters' dual-hydraulic AS350 B3e helicopter's (1) preflight hydraulic check, which depleted hydraulic pressure in the tail rotor hydraulic circuit, and (2) lack of salient alerting to the pilot that hydraulic pressure was not restored before takeoff. Such alerting might have cued the pilot to his failure to reset the yaw servo hydraulic switch to its correct position during the preflight hydraulic check, which resulted in a lack of hydraulic boost to the pedal controls, high pedal forces, and a subsequent loss of control after takeoff. Contributing to the accident was the pilot's failure to perform a hover check after liftoff, which would have alerted him to the pedal control anomaly at an altitude that could have allowed him to safely land the helicopter. Contributing to the severity of the injuries was the helicopter's fuel system, which was not crash resistant and facilitated a fuel-fed postcrash fire.
Occurrence sequence
4 stepsNTSB coding · CICTT taxonomy- 1 · TakeoffPreflight or dispatch event
- 2 · TakeoffLoss of control in flightdefining event
- 3 · Uncontrolled descentCollision with terr/obj (non-CFIT)
- 4 · Post-impactFire/smoke (post-impact)
Findings
11 causal · 0 contributing- CAUSEOrganizational issues › Development › Design › Equipment design — Manufacturer
- CAUSEOrganizational issues › Development › Design › Design of document/info — Manufacturer
- CAUSEAircraft › Aircraft systems › Hydraulic power system — Design
- CAUSEAircraft › Aircraft systems › Hydraulic power system › Hydraulic, indicating system — Design
- CAUSEPersonnel issues › Task performance › Use of equip/info › Use of equip/system — Pilot
- CAUSEPersonnel issues › Action/decision › Action › Forgotten action/omission — Pilot
- CAUSEPersonnel issues › Task performance › Use of equip/info › Use of checklist — Pilot
- CAUSEPersonnel issues › Task performance › Use of equip/info › Aircraft control — Pilot
- CAUSEPersonnel issues › Action/decision › Action › Lack of action — Pilot
- CAUSEPersonnel issues › Task performance › Use of equip/info › Use of policy/procedure — Pilot
- CAUSEAircraft › Aircraft systems › Fuel system — Design
Safety recommendations
6 issuedwhat changed because of this accidentTO THE FEDERAL AVIATION ADMINISTRATION: Require that existing Airbus Helicopters dual-hydraulic AS350-series helicopters be equipped with a visual and an aural alert for the loss of hydraulic boost to the pedal controls, which would result in increased pedal loads.
TO AIRBUS HELICOPTERS: For newly manufactured dual-hydraulic AS350-series helicopters, assess and implement changes to the dual hydraulic system that would both ensure pedal control hydraulic assistance and mitigate the possibility of pilot error during any check of the hydraulic system.
TO AIRBUS HELICOPTERS: For existing dual-hydraulic AS350-series helicopters, assess and implement changes to the dual hydraulic system that would both ensure pedal control hydraulic assistance and mitigate the possibility of pilot error during any check of the hydraulic system.
TO THE FEDERAL AVIATION ADMINISTRATION AND THE EUROPEAN AVIATION SAFETY AGENCY: After the actions requested in Safety Recommendation A-17-10 are completed, require operators of Airbus Helicopters dual-hydraulic AS350-series helicopters to incorporate changes to the dual hydraulic system to both ensure pedal control hydraulic assistance and mitigate the possibility of pilot error during any check of the hydraulic system.
TO THE ASSOCIATION OF CRITICAL CARE TRANSPORT: In collaboration with the Association of Air Medical Services and the Air Medical Operators Association, establish a working group to develop and distribute guidelines, for those who purchase, lease, or contract for helicopters, regarding the equipment and systems that would enhance the helicopters’ crashworthiness, including, at a minimum, a crash-resistant fuel system and energy-absorbing seats.
TO THE ASSOCIATION OF AIR MEDICAL SERVICES AND AIR MEDICAL OPERATORS ASSOCIATION: Work with the Association of Critical Care Transport to establish a working group to develop and distribute guidelines, for those who purchase, lease, or contract for helicopters, regarding the equipment and systems that would enhance the helicopters’ crashworthiness, including, at a minimum, a crash-resistant fuel system and energy-absorbing seats.
NTSB analysis
from the final reportThe NTSB's full report is available at http://www.ntsb.gov/investigations/AccidentReports/Pages/AccidentReports.aspx. The Aircraft Accident Report number is NTSB/AAR-17/01. On July 3, 2015, about 1339 mountain daylight time, an Airbus Helicopters AS350 B3e helicopter, N390LG, registered to and operated by Air Methods Corporation, lifted off from the Summit Medical Center Heliport, Frisco, Colorado, and then crashed into a parking lot; the impact point was located 360 feet southwest of the ground-based helipad. The pilot was fatally injured, and the two flight nurses were seriously injured. The helicopter was destroyed by impact forces and a postcrash fire. The flight was conducted under the provisions of 14 Code of Federal Regulations Part 135 on a company flight plan. Visual meteorological conditions prevailed at the time of the accident.