What happened
On April 4, 2009, a Bell 2/22 helicopter, registration PP-MEH, operated by OMNI Táxi Aéreo Ltda., was performing a takeoff from platform SS64 in the Campos Basin, Brazil. Shortly after takeoff, while the aircraft was climbing through 350 feet with a rate of climb of 500 feet per minute and the landing gear still extended, the number one engine experienced a sudden and total loss of all parameters, resulting in an engine flameout.
The flight crew immediately transitioned to single-engine flight procedures. Upon reaching a safe minimum altitude, the crew executed the emergency checklist. The commander elected to proceed to the alternative airfield at Campos (SBCP), which offered closer proximity and better meteorological conditions. The aircraft landed safely at the destination, and all occupants—two pilots and one passenger—remained uninjured.
The investigation
CENIPA investigators examined the aircraft's maintenance history and the mechanical state of the engine components. Post-incident inspections of the engine number one fuel valve electrical system revealed an abnormality in the fuel valve activation switch.
Technical analysis established that the switch utilized a spring mechanism that would compress when held in the normal position and extend when released. Due to engine vibrations, this spring could fail, causing the switch to move to the released position, which closed the fuel valve and interrupted the fuel supply.
Investigators also discovered that a Technical Bulletin (TB 222-04-171) had been issued by the manufacturer on November 6, 2003. This bulletin recommended modifying the switch command logic—inverting the position so that the extended position allowed the valve to remain open—to prevent such failures. The investigation found that the operator had not implemented this recommended modification upon acquiring the aircraft.
Findings
- The primary cause of the engine failure was the failure to implement a recommended technical bulletin regarding the fuel valve switch.
- The design of the fuel valve switch mechanism was susceptible to movement caused by engine vibrations.
- Maintenance oversight contributed to the risk, as the recommended modification to invert the switch command was not performed.
- The crew successfully managed the single-engine emergency and executed a safe landing at the alternative airport.