What happened
On 27 September 2019, a Cessna 172, registration 9V-BOQ, was performing solo circuit training at Seletar Airport, Singapore. During the fourth landing attempt of the flight, the student pilot experienced a slight wind shear just before touchdown. Following the main wheels making contact with the runway, the aircraft encountered a gust of wind that caused it to veer toward the right.
In an attempt to maintain the centerline, the pilot applied brakes and control inputs. However, as the aircraft approached the edge of the runway, the pilot feared that excessive control inputs might cause the wingtip to strike the ground. Consequently, the aircraft exited the runway onto the grass area. Once the aircraft had slowed, the pilot successfully steered the Cessna 172 back onto the runway. There were no injuries and no damage to the aircraft or the airport infrastructure.
The investigation
Investigators examined the meteorological conditions and the pilot's decision-making process. While the pilot reported a gust from the left, meteorological data indicated the wind was actually coming from the right. The investigation suggested that a momentary increase in the crosswind likely caused the aircraft to weather vane toward the right.
Because the aircraft was not equipped with a flight recorder, the exact sequence and magnitude of the pilot's control inputs could not be definitively determined. However, post-incident inspections of the rudder and aileron systems revealed no mechanical anomalies.
Findings
- The pilot detected wind shear prior to touchdown but decided to continue the landing instead of performing a go-around.
- The aircraft's deviation was likely caused by a sudden increase in crosswind strength from the right, causing the aircraft to yaw right.
- The pilot's decision to limit control inputs to avoid a wingtip strike contributed to the aircraft exiting the runway onto the grass.
Safety action
Following the incident, the Seletar Flying Club implemented several safety measures:
- The incident and lessons learned were presented to club members during a safety forum focusing on go-around decisions and ground control.
- The flight instructor updated the training syllabus to emphasize aircraft control on the ground and the proper use of the rudder.
- The student pilot underwent three hours of additional supervised training on crosswind techniques and circuit maneuvers before resuming solo operations.