AO-2020-002

Figure 6 from the final report. The glider wreckage is shown in an aerial photo of the accident site. The wings are embedded in trees and bushes on the mountainside. The tail section has broken off. The cockpit structure is also broken off and in numerous pieces.
Fig.6 from the final report
Glider, Schleicher ASK21, ZK-GTG, Impact with Terrain, Mount Tauhara, Taupō, 31 May 2020
Status
Closed
Occurrence Date
Report Publication Date
Jurisdiction
NZ
What happened
On 31 May 2020, an instructor from the Taupo Gliding Club conducted a trial flight with a short-term member (the student). The flight was the second of the day for the instructor, who had previously flown a similar trial flight with another short-term member.

The instructor flew over the Mount Tauhara walking track near the southeastern face of the mountain. The glider was observed by witnesses walking the track from near the trig station on the summit. The glider was last seen flying past the trig station at about the same height as the trig station, but on the downwind side and with the left wing down. The witnesses saw and heard the glider’s left wing strike scrub and, as it subsequently went out of their sight, they heard further sounds of impact. Neither occupant survived the accident.

Why it happened
The Transport Accident Investigation Commission found that the glider impacted terrain while the instructor was likely attempting to escape from a situation where the glider was at a low height above the mountain and downwind of the ridge face. Despite the instructor’s efforts to manoeuvre the glider away from rising terrain on the right-hand side, a collision with the terrain became unavoidable.

The Commission found that the Taupō Gliding Club had limited systems in place to positively verify that pilots had an appropriate level of competency to soar on Mount Tauhara.

The Commission also found that the Taupō Gliding Club procedures for instructor training and ongoing competency were not in accordance with Gliding New Zealand’s Manual of Approved Procedures.

The Commission made two safety recommendations:
•One to the Taupō Gliding Club to develop a system to ensure local instructors are able to positively verify that pilots have appropriate levels of competency to ridge soar on Mount Tauhara and safely conduct training flights on the ridge.
•One to Gliding New Zealand to review how gliding club instructors are trained and clubs are audited, and then take corrective action to ensure that all new instructors are consistently trained to the standards set out in the Manual of Approved Procedures.

What we can learn
Ridge soaring has inherent risks due to factors such as turbulent wind conditions, unpredictable updrafts and proximity to terrain, and pilots must be competent in the correct techniques in order to manage these risks.

Trial flights should be conducted in environments that meet the intent of the flights without introducing unnecessary risks.

Who may benefit
Gliding clubs, glider pilots, instructors and personnel involved with glider flying activities and aviation regulation within New Zealand will benefit from this report.

Location
near Taupo (-38.693080,176.162583) [may be approximate]