Following a local flight the pilot positioned the glider to join the circuit for a landing on the grass strip 24. The wind velocity was reported as 240 to 280 degrees at 10-15 knots with occasional gusts to 18 knots. After lining up on final approach, the pilot inadvertently raised the landing gear instead of extending the air brakes. As the approach continued it became apparent the glider would overshoot the runway. The glider was banked to the right to remain within the confines of the aerodrome. The right wing tip struck the ground and the glider ground looped.

Circumstances:

The pilot, in company with another aircraft, had been carrying out aerial top dressing operations from an airstrip located along the top of a ridge line. The conditions were calm, and the pilot, who had limited aerial agricultural experience, was relaxed and enjoying the flying. Returning to the airstrip at the completion of a sortie, the pilot made a glide approach and crossed the threshold just as the other aircraft was departing with a full load. Just before touch down, the aircraft encountered turbulence and dropped the left wing, then veered sharply to the left over the side of the ridge. The pilot attempted to regain the strip without increasing power.

However, the aircraft failed to respond and touched down on the sloping terrain at the side of the strip. During the landing roll he attempted to steer the aircraft up the slope, but it collided with a stack of timber which caused the right-hand main landing gear leg to separate. The pilot subsequently advised that he had been complacent and had not given sufficient attention to the landing. He had then encountered wake turbulence, generated from behind the departing aircraft, which had not had time to dissipate in the calm conditions. It had not occurred to him to apply full power and go-around.

Circumstances:

The pilot reported that he had planned to fly a triangular course from Cunderdin to Cunderdin. After spending over 3.5 hours, in difficult weather conditions, to get to his first turning point the pilot elected to return direct to Cunderdin. When he arrived back at Cunderdin, the pilot spent 45 minutes in the local area before returning to land. The pilot decided to land well into the shorter of the two runways, to reduce the effort required to move the glider into a hangar however, he had forgotten that the wheel brake was not working. The aircraft touched down over halfway down the 1200 metre runway. With 300 metres to run, the pilot became concerned at the slow rate of deceleration, and it was at this point he remembered the unserviceable wheel brake. Although he believed it would not be necessary the pilot decided he would intentionally ground loop the aircraft when there was 50 metres to run if it was not slowing adequately. The aircraft's speed was still close to 20 knots, when there was 50 metres to run, and the pilot was forced to attempt a ground loop. The ground loop attempt only succeeded in altering the direction of travel and the aircraft stopped after crossing a ditch and hitting a fence. The pilot advised that he did not think to use the airbrake to slow the aircraft once it was on the runway.

The pilot and passengers were overseas visitors taking part in an aerial safari. The flight apparently proceeded normally until a series of garbled radio transmissions were recorded from the aircraft, which then failed to reply to further calls. Despite an intensive search, the wreckage of the aircraft was not found for 2 months. It was evident that the aircraft had collided with trees at high speed while in a steep descending attitude. Examination of the wreckage did not reveal any pre-impact fault that could have contributed to the accident. A post analysis of the prevailing weather conditions indicated that areas of rain showers and low cloud existed over the higher terrain in the region. It is probable that the pilot lost control of the aircraft after inadvertently entering cloud.

The aircraft was taxied in the early dawn light with an overcast sky and drizzle. The aerodrome pilot-activated lights were not on nor were the aircraft landing and taxi lights. The aircraft was inadvertently taxied off the taxiway. During attempts to return to the taxiway the nose-wheel of the aircraft entered soft ground and was broken off.

Circumstances:

During the flight the engine surged without warning and the pilot elected to land in a cleared area, to investigate the engine problem. The engine failed completely during the latter stage of the approach resulting in a heavy landing short of the cleared area. Subsequent investigation by the pilot revealed that the auxiliary fuel tank was completely empty. The main fuel gauge indicated that the main fuel tank was full of fuel. The two fuel tanks cannot be selected individually and fuel from both is supplied simultaneously. On this occasion it appears that only fuel from the auxiliary fuel tank reached the carburettor. The duration of the flight is consistent with this assumption. Examination by the company maintenance organisation revealed that a plastic hose in the main fuel tank vent line was pinched, possibly during the accident. Maintenance had been carried out before the previous flight, which had lasted 40 minutes. However, the work entailed the removal of the auxiliary fuel tank during which the main fuel vent line was not moved. No other fault was found.

Circumstances:

The pilot had been spraying rice fields when the aircraft began to vibrate severely and lose height. He began a turn into wind to position the aircraft for a forced landing in a dry paddock, adjacent to the field under treatment. During the turn the aircraft struck a small earth bank which tore off the main landing gear. The reason for the vibration has not yet been established. However, a piston failure is suspected as pieces of piston and piston ring material were found in the engine sump.

Circumstances:

The pilot intended to land on a small knoll in the centre of a large, cleared area in heavily timbered country. During the flare to land over a large depression, the pilot noticed a lack of power accompanied by the Low Rotor RPM Warning Horn. He lowered the collective control and wound the throttle to maximum in an attempt to regain rotor RPM. In doing so, he oversped the engine and rotor, and subsequently overshot the landing site. He was convinced that he had a genuine power problem and elected to land in a gully beyond the knoll. The tail rotor struck ground in the steeply sloping gully, resulting in the tail boom being cut off by the main rotor. The cabin came to rest on a heap of storm debris. During later investigation, the engine was ground run successfully. A small fuel leak existed at the carburettor, but this did not affect the fuel supply to the engine. The pilot had not received any training in ridge line operations. He had made his approach using visual cues only, which can result in a steep final approach accompanied by a high rate of closure. In addition, the pilot was unaware of the local wind velocity, and the aircraft was probably subject to local airflow effects. While attempting to compensate for these, it is probable that the pilot over-pitched the main rotor blades leading to a temporary reduction in main rotor RPM. He subsequently misread the symptoms as an engine malfunction.

Significant Factors:

The following factors were considered relevant to the development of the accident:

1. The pilot was inexperienced in ridge line operations.

2. The pilot did not maintain adequate rotor RPM during the latter stages of the approach.

3. The pilot considered that the engine had failed

 4. The aircraft was force landed on unsuitable terrain.

Prior to flying the club's single seat glider, the visiting pilot was required to undergo a dual check. His first check flight was conducted in VH-IKB by the club's Chief Flying Instructor who was not satisfied and required another flight. The second take-off appeared to be normal but after lift off the glider entered an uncontrolled climb. The pilot operated the cable release and handed over control to the instructor There was no elevator control available and the glider climbed to about 200 feet above ground level where it stalled and turned left through about 90 degrees. The glider descended steeply and impacted the ground on the left wingtip followed by the nose and right wingtip. It came to rest after sliding about 20 metres. After the accident it was found that the cast-alloy elevator horn had failed as the result of a single overload. Examination of the casting revealed widespread and excessive porosity resulting in a degradation of the material static strength including its resistance to impulsively applied loads. The investigation established that, during the previous landing, the glider had touched down heavily and there was a "sharp" impact in the tail area. Prior to the accident flight, the tail of the glider was visually inspected but no evidence was found of any damage. It was not possible to determine positively if the casting failed during the accident or on the previous landing.

After refuelling, the pilot found one of the tanks contaminated with water. The fuel was drained from the tank and clean fuel added. No contamination was found in the subsequent check of the fuel in the tank. The aircraft was then washed using a high pressure water hose. During the following flight, the engines began to run roughly and the pilot decided to carry out a landing in a paddock. The surface of the paddock was rough and the aircraft bounced heavily and groundlooped, collapsing the right gear. The investigation revealed that water had been present in the fuel system for sometime. Because of the design of the fuel system it is not possible to drain the lowest point of the fuel tank while the aircraft is parked. It is probable that the engine rough running was caused by a combination of contaminated fuel and a sticking valve.