Collision with terrain involving a Glasflugel Hornet, VH-GEZ, Benalla Aerodrome, Victoria, on 4 December 1995

199504285

Summary

The glider was being test flown after major maintenance had been completed. During lift off the pilot lost control and the aircraft cartwheeled. The pilot received minor injuries, and the glider was substantially damaged.

Investigation found that the ailerons had been connected in the reverse sense. During the maintenance, reassembly, rigging and preflight the glider had passed through four stages of inspection, all of which failed to detect the incorrect rigging of the ailerons.

It was found that 10 types of glider operated in Australia are fitted with common aileron drive gimbals that can be physically fitted to the incorrect side of the aircraft, thereby reversing the sense of the control.

Immediately after the accident the Gliding Federation of Australia issued an Operations Advice Notice advising details of the accident. The notice made the point that crossed controls had occurred before and that an Airworthiness Advice Notice had been issued in 1980 covering the subject. This notice stated, 'this incident emphasises the dangers of complacency; we have come to expect things to operate correctly and therefore assume that if something is working, it is working correctly'.

The Operations Advice Notice made three recommendations relating to the principles of assuring correct sense and the avoidance of external distraction during preflight inspections.

The Gliding Federation also issued an Airworthiness Directive requiring, on the subject gliders, gimbals for the left wing to be painted bright red and for the gimbals for the right wing to be paint bright green. This action is to be performed at the next annual inspection.

Occurrence summary

Investigation number 199504285
Occurrence date 04/12/1995
Location Benalla Aerodrome
State Victoria
Report release date 10/09/1996
Report status Final
Investigation type Occurrence Investigation
Investigation status Completed
Mode of transport Aviation
Aviation occurrence category Collision with terrain
Occurrence class Accident
Highest injury level Minor

Aircraft details

Manufacturer Glasflugel
Model Hornet
Registration VH-GEZ
Sector Other
Operation type Private
Departure point Benalla Vic
Destination Benalla Vic
Damage Substantial