Engine failure leads to forced landing after improper refuelling

Casualties unknown • CA

A Robinson R44 helicopter experienced engine power loss during takeoff following the accidental introduction of Jet A-1 fuel into its tanks.

What happened

During a visual flight rules flight from Port-Menier, Quebec, to Québec, Quebec, a Robinson R44 Raven II helicopter, registered C-FNZO, experienced a loss of engine power during its initial climb from Forestville. The aircraft, which was part of a group of three helicopters, was forced to perform an emergency landing in a residential area. The two occupants of the aircraft sustained minor injuries and were transported to a hospital. The helicopter suffered substantial damage, while two accompanying helicopters landed safely nearby without damage.

The investigation

The investigation established that during a scheduled stopover in Forestville, the three helicopters were refuelled with Jet A-1 fuel instead of the required AVGAS 100LL. The refueller, relying on previous experience and lacking specific training regarding aircraft that require AVGAS, prepared the fuel hose before the aircraft arrived. Because the hose was already positioned, the pilots assumed the correct fuel type had been confirmed via telephone.

Several factors contributed to the error. The refueller operated alone, resulting in only one of the two fuel tanks being filled on each aircraft. Furthermore, the refueller did not follow manufacturer recommendations regarding the order of filling the tanks, partly because the fuel type labels on the pump were not clearly visible from the ground. During the departure, the pilots did not perform a full pre-flight inspection, which included failing to take fuel samples or verify fuel quantities on the gauges. Additionally, the invoices provided after refuelling clearly indicated the fuel type and the volume delivered, but the pilots only noted the low cost of the fuel.

Findings

  • The use of Jet A-1 fuel caused the engine to lose power during the climb.
  • The refueller's training was inadequate and did not cover the specific requirements for AVGAS-dependent aircraft.
  • A modified Jet A-1 nozzle, which had been made smaller to accommodate other aircraft, allowed the hose to fit the Robinson R44 Raven II fuel openings, removing a physical barrier to error.
  • The pilots failed to supervise the refuelling process and omitted critical steps from their pre-flight checklist that would have identified the incorrect fuel.
  • There are currently no specific Canadian regulations governing the training of aerodrome refuellers or the diameter of helicopter fuel filler openings.

Probable cause

The engine power loss was caused by the introduction of Jet A-1 fuel into an engine designed for AVGAS, a mistake facilitated by inadequate refueller training, the use of a compatible nozzle size, and the pilots' failure to verify fuel types during pre-flight inspections.

Frequently asked questions

What happened in the 2011-03-01 Forestville, Quebec accident near CA?

A Robinson R44 helicopter experienced engine power loss during takeoff following the accidental introduction of Jet A-1 fuel into its tanks.

What aircraft was involved and where did it happen?

The accident on 2011-03-01 involved a Forestville, Quebec, operated by Robinson R44 Raven II (Helicopter) C-FNZO, at CA.

What was the probable cause of the accident?

The engine power loss was caused by the introduction of Jet A-1 fuel into an engine designed for AVGAS, a mistake facilitated by inadequate refueller training, the use of a compatible nozzle size, and the pilots' failure to verify fuel types during pre-flight inspections.

Loading the flight search…