What happened
On November 30, 2000, a Diamond HK 36 TTC, registration PH-1158, was performing a recreational flight from Hoogeveen to Teuge. During the final approach to runway 27, the pilot executed a slip maneuver with the airbrakes extended. As the aircraft approached the runway at an extremely low altitude, the pilot applied full power to prevent the aircraft from striking the grass short of the threshold. This sudden application of power caused the nose to pitch up to approximately 45 degrees. At an altitude of only 65 to 80 feet, the aircraft entered a stall, causing the nose to drop sharply to 40 degrees. The aircraft struck the runway with high vertical velocity, causing the airframe to disintegrate. The impact resulted in one fatality and one serious injury.
The investigation
The investigation examined the flight path, the aircraft's technical condition, and the pilot's experience. Investigators found that the aircraft was airworthy and that the center of gravity was within limits. While the aircraft was slightly overweight, this was not a contributing factor. The investigation also noted that the pilot deviated from standard arrival procedures and failed to notice other aircraft in the vicinity near the Sierra reporting point. The wreckage analysis showed that the propeller blades and landing gear failed upon impact, and the cockpit canopy disintegrated.
Findings
Several factors contributed to the accident. The primary cause was that the aircraft stalled during a go-around maneuver at an altitude too low to recover. The pilot's actions were influenced by several contributing factors, including:
- A lack of experience operating the Diamond HK 36 TTC, specifically regarding the handling characteristics of this model.
- Limited experience flying from the left seat in a side-by-side cockpit configuration.
- Difficulty managing the transition of control from the right hand to the left hand during the critical moment of the go-around.
- The decision to maintain extended airbrakes during the power application, which may have hindered the recovery.
Safety action
Following the investigation, a recommendation was made to the Ministry of Transport and Water Management and the Gliding Department of the Royal Dutch Aeronautical Association. The recommendation suggests investigating the creation of guidelines to promote thorough transition training when moving between different types of touring motor gliders (TMGs).