Loss of control

The aircraft was being operated from a clay pan strip on a dry lake bed. There had been no rain for approximately 48 hours and the pilot had flown his aircraft from the strip twice in that period. On each occasion he had taxied along the strip to the west and taken off into the east. However, on this occasion, he was departing to the west and the take-off run was along the section of strip used during the previous taxying. The pilot stated that during the take-off roll, the aircraft appeared to break through the clay surface crust and drag to one side. He said that he reduced power and attempted to bring the aircraft to a full stop before it ran off the side of the strip. However, the nosewheel broke through the surface and bogged in the soft clay causing the aircraft to overturn.

The pilot was taking three friends on a local sightseeing flight. He calculated that the aircraft would be close to maximum all-up-weight and from the Aircraft Performance Chart, concluded that a strip length of 700 metres was required with 9 degrees flap selected. He had earlier used a vehicle to measure the ALA length as 900 metres. Witnesses reported that the aircraft became airborne about three quarters of the way along the strip, flew level for a time, and slowly drifted left before climbing sharply over a row of trees. At this point the left wing dropped so the pilot retracted the flap and applied right rudder. He did not retract the landing gear. The aircraft descended and struck the ground right aileron first before skidding left through some 140 degrees. The nose and right main landing gear were torn off. The investigation revealed that the aircraft was approximately 5 percent above maximum take-off weight. The Aircraft Peformance Chart indicated that for the prevailing conditions, the required strip length was 975 metres. The strip itself was 800 metres long. An inspection of the aircraft did not reveal any faults that may have contributed to the occurrence.

Circumstances:

This was the student's first session on practice forced landings. The instructor demonstrated a forced landing approach and then positioned the aircraft for the student to practice an approach. The instructor intended to demonstrate to the student the dangers of trying to stretch the glide. The approach was flown by the student into wind with full flaps set, descending to a low height with the speed reducing to 55 knots. The student failed to respond to the instructor's call to watch the airspeed. The instructor took control, applying full power, but too late to avert the descent. The aircraft port wing tip contacted a bush, and the resulted ground contact caused the nose gear to collapse. The instructor estimated the wind as from the north-west at 15-20 knots and thought there was probably wind shear at low level, which contributed to causing the ground contact.

It was reported that the flight proceeded normally until during the flare. The glider was lined up with the strip, but during the hold-off it drifted to the right and touched down on the edge of the marked, 50 metre wide strip. The landing roll continued off the runway and the starboard wing struck a tree 20 metres from the edge of the strip. The landing was conducted in 4 to 8 knot crosswind conditions. During the hold-off the student pilot applied excessive rudder when aligning the aircraft with the strip prior to touchdown.

The more experienced pilot was occupying the rear control position, which did not have tail rotor control pedals, while another pilot flew the aircraft. During the approach to land the pilot in the rear seat became concerned when the airspeed decayed and he pushed the cyclic control forward to initiate a go around. The aircraft yawed to the right, control was lost and the aircraft struck the ground heavily, coming to rest on its right side. The inexperienced pilot occupying the front seat had been surprised when the rear seat pilot had taken control during the approach. Although he had been instructed to apply left pedal, it is likely that his delay in doing so, prevented control from being regained before the helicopter struck the ground. Inspection of the aircraft revealed that forward cyclic control movement was limited by incorrect rigging. This may have also contributed to the loss of control.

The pilot was landing in gusting wind conditions with a cross-wind from the left. After the left wheel had touched down and before the right wheel had been grounded a gust of wind lifted the left wing, causing the aircraft to drift to the right. Attempts by the pilot to re-land were unsuccessful and a go-around was initiated. The aircraft subsequently collided with a fence post and came to rest about 180 metres off the side of the runway. The aircraft encountered a very strong wind gust at the time of touchdown. The pilot delayed action in initiating a go-around and when power was applied the aircraft was unable to out-climb the rising terrain while flying downwind.

Circumstances:

The pilot reported that there had been recent heavy rain on the strip. Well into the landing roll, the aircraft encountered an area of water and skidded to the left. The left wheel then entered soft ground and swung the aircraft further left, resulting in the left main landing gear striking a steel framed cone marker. This accident was not the subject of an on-site investigation.

Circumstances:

The pilot had continued gliding at altitude despite deteriorating weather conditions. When he returned to the circuit, he found that a strong wind was blowing. During the approach to land the pilot found that he had to hold a heading up to 45 degrees off runway heading to counter the right crosswind. After flaring to land the glider drifted and weather-cocked. It came to rest after passing through a barbed wire fence.

Circumstances:

The aircraft was making a crosswind landing on runway 22. The pilot reported that as the aircraft was touching down on the main wheels it was struck by a strong gust, blowing it from the centreline. Because grassed areas were available, the pilot did not attempt to regain the centreline. The aircraft continued to diverge from the runway until it struck a ditch.

Circumstances:

The aircraft took off, made one circuit of the field, and was flying parallel to the take-off direction at approximately 250 ft when it was observed to dive almost vertically into the ground. The engine was operating at a high-power setting at impact, and no faults were found with the aircraft which may have been factors in the accident. The factors which led to the loss of control could not be determined.