What happened
On 13 August 2014, a DH 115 Vampire MK55, registration ZU-VMP, was performing a private flight at Wonderboom Aerodrome. After departing from the airport's general flying area, the pilot attempted to land on Runway 29. During the landing roll, the aircraft experienced intense vibrations in the nose gear upon its initial contact with the runway. The pilot attempted to lift the nose gear to mitigate the shaking, but upon a second touchdown, the nose landing gear assembly failed completely.
The resulting collapse caused the aircraft to skid along the asphalt surface. The friction between the metal components and the runway generated smoke and visible flames, prompting an emergency declaration and the dispatch of airport fire and rescue services. The aircraft eventually came to a halt near the intersection of Runway 24 and Taxiway C. Both occupants of the aircraft escaped the incident without injury.
The investigation
An investigation by the SACAA AIID focused on the mechanical failure of the nose gear and the pilot's landing technique. The inquiry examined the aircraft's maintenance history, noting that the airframe had flown only 0.83 hours since its last major inspection. Investigators also reviewed the pilot's experience, noting that while the pilot held an Airline Transport Pilot license and possessed extensive experience in large commercial transport aircraft, they had very limited recent experience with this specific vintage jet type, having accumulated only 0.6 hours on the type in the 90 days preceding the accident.
Physical evidence regarding the specific failure of the attachment points was limited because the skidding motion and friction against the runway surface destroyed much of the critical hardware, including the wheel fork assembly attachment and connecting pins. However, the investigation utilized expert testimony and comparative samples of similar fatigue damage to reconstruct the event.
Findings
- The nose landing gear collapsed due to excessive shimmy vibrations occurring during the landing roll.
- The pilot's landing speed was high, as evidenced by the ability to lift the nose gear off the runway after the initial vibration was detected.
- The pilot utilized an improper landing technique; rather than allowing the nose gear to settle naturally as speed reduced, the pilot attempted to manage the gear manually during a high-speed roll.
- The pilot'ost lack of recent familiarity with the specific handling characteristics of the DH 115 Vampire MK55 contributed to the error.