What happened
On 7 October 2012, a Britten-Norman BN2A-26 aircraft, registration VP-MON, was performing a scheduled commercial passenger flight from V.C. Bird International Airport in Antigua to Montserrat. The flight was the fourth sector of the day for the operator, Fly Montserrat.
During the takeoff roll on Runway 07, the aircraft was operating with a 10-knot tailwind. Shortly after liftoff, witnesses observed the aircraft climb to approximately 200 to 300 feet before it appeared to sink and subsequently yaw and roll to the right. The aircraft entered an incipient spin, with a passenger noting that the stall warning light remained illuminated until the moment of impact. The aircraft struck the ground in a steep right-wing-low attitude, resulting in two fatalities and one serious injury among the passengers, while the pilot was also killed. The aircraft was destroyed.
The investigation
The investigation examined the aircraft's fuel system, maintenance records, and the pilot's training history. Investigators discovered that the aircraft's fuel filler caps were a newer design, while the filler necks were the original, older standard. This mismatch, combined with corrosion on the right-hand filler neck, allowed rainwater to leak into the fuel tank during a period of heavy rainfall prior to departure.
Analysis of the fuel system revealed that the right-hand engine's fuel supply was contaminated with a significant amount of water. The investigation also found that the fuel suction filters were of an older design that was more susceptible to being inundated by water when the aircraft's nose pitched up during takeoff. Furthermore, the pilot's previous employment records indicated historical difficulties with maintaining airspeed and directional control, though the operator had not reviewed these specific training details.
Findings
- The primary cause of the accident was the presence of water in the right-hand fuel tank, which entered the engine fuel system following heavy rainfall and a faulty fuel cap seal.
- The failure of the right-hand engine occurred shortly after takeoff due to this water contamination.
- The aircraft entered a spin because control was not maintained after the engine failure.
- A lack of a pre-flight fuel drain check meant the water contamination went undetected.
- The use of an older-standard fuel suction filter made the engine more vulnerable to water ingestion during the takeoff rotation.
- The aircraft was operating with a tailwind that exceeded the maximum permitted takeoff weight performance limits.