What happened
On the morning of 10 February 2014, a Cessna Caravan C208B, registration ZS-EPZ, was preparing for a commercial charter flight from MalaMala aerodrome to O R Tambo International Airport. The aircraft was carrying two pilots and 11 passengers. Following a routine engine start and pre-flight procedures, the pilot in command began taxiing toward the threshold of runway 16.
As the aircraft proceeded down a slope on the taxiway, it began to drift toward the left centerline. The pilot attempted to apply corrective steering to the right, but the maneuver was unsuccessful. The aircraft continued to veer left, eventually departing the taxiway surface. In an attempt to stop the movement, the pilot applied maximum braking pressure, and subsequently directed the first officer to apply the right-side brakes, but no deceleration occurred. The aircraft continued rolling until it entered a ditch parallel to the taxiway and collided with an embankment. While the aircraft sustained substantial damage, there were no injuries among the 13 people on board.
The investigation
SACAA AIID investigators examined the mechanical state of the aircraft and the actions of the flight crew. The investigation reviewed the aircraft's maintenance history, noting that the plane had completed a mandatory periodic inspection 70.9 hours prior to the event. Documentation confirmed that the aircraft's weight and balance were within legal limits and that all necessary airworthiness certificates and operator licenses were valid.
Technical inspections of the aircraft's braking and rudder systems were conducted. Despite the crew's reports during the event that the brakes and rudder had failed, the investigation found no mechanical anomalies or deficiencies in the braking or steering systems.
Findings
- The aircraft was operating within its maximum takeoff weight and center of gravity limits.
- The weather conditions at the time of the accident were clear with good visibility.
- The mechanical systems, specifically the brakes and rudder, were fully functional and showed no signs of failure.
- The primary cause of the excursion was poor airmanship.
- The crew failed to maintain adequate directional control and situational awareness during the taxi phase.