What happened
On the evening of 21 May 2015, a Villa Air ATR 72-212A, registration 8Q-VAS, was conducting a scheduled flight from Fuamulah Domestic Airport to Gan International Airport. The flight was carrying 58 passengers and 4 crew members. During the approach to runway 28, the flight crew encountered heavy rain and reduced visibility.
As the aircraft touched down, it landed approximately 8.5 meters to the left of the runway centerline. The aircraft subsequently skidded left, exiting the paved surface and traveling through the grass for approximately 213 meters before returning to the runway. The aircraft was then able to taxi back to the apron. There were no injuries to the passengers or crew.
The investigation
The AICC investigation examined flight data recorder (FDR) and cockpit voice recorder (CVR) data, alongside interviews with the flight crew and air traffic control records. The investigation focused on the aircraft's approach profile, the environmental conditions, and the status of the aircraft's equipment.
Investigators noted that the aircraft was operating with an unserviceable left-hand windshield wiper, which had been deferred under the Minimum Equipment List (MEL). However, the investigation found that the conditions for this deferral—specifically that no precipitation was forecasted—were not met, as heavy rain was present during the arrival. Additionally, the investigation reviewed the runway surface conditions, noting the presence of standing water and moss growth on the touchdown zone.
Findings
- The primary cause of the excursion was a loss of control after touchdown due to the aquaplaning effect.
- The aircraft approached the runway at a speed 22 knots higher than the recommended approach speed (VAPP) and below the standard 3-degree descent gradient.
- The flight crew operated the aircraft in violation of regulations regarding windshield wiper deferrals, as heavy rain was occurring during the operation.
- Contributing factors included standing water on the runway, a landing offset from the centerline, and the presence of moss on the touchdown zone.
- The aircraft sustained damage to the right-hand propeller blades, the main landing gear wheels, and the tail skid.