Circumstances:

The pilot reported that the helicopter was taken off into the hover above the helideck, where power and performance checks were carried out. A left pedal turn at the hover was then initiated over the helideck markings to position the helicopter for take-off into a 10-15 knot wind. On completion of the turn a loud bang was heard, and a vibration felt. The helicopter was landed on the helideck, shutdown and passengers disembarked. The tail rotor had struck a communications receiver dish antenna located outside the helideck area. An inspection of the helicopter failed to reveal any pre-existing faults which may have prevented the pilot from holding the helicopter in a steady hover during the turn. This accident was not the subject of an on-scene investigation.

The pilot had been spraying a wheat crop for about 30 minutes. He advised that difficulties were encountered with the stabilisation of the spray pressure. While attempting to adjust the pressure control he temporarily forgot the proximity of three high voltage power lines which crossed the crop. The aircraft collided with these lines and pitched down steeply to the ground. Fire broke out on impact and engulfed the wreckage.

During spraying operations the engine began to run very roughly and lost a considerable amount of power. The pilot considered that insufficient power remained to permit him to divert to a suitable landing area and he attempted to land straight ahead. Towards the end of the landing roll the aircraft struck a contour bank and the right landing gear collapsed. The cause of the power loss could not be positively identified, but was probably related to excessive spark plug fouling.

The pilot was participating in a 500 kilometres cross country gliding competition. Atmospheric conditions were not favourable for prolonged soaring flight, and none of the other participants was able to cover any significant distance. However, this particular aircraft departed on the planned track, and the next reported sighting was about 3 kilometres from the accident site. At this time the aircraft was circling at approximately 300 feet above the ground and tracking to the north-west. No further sightings were reported, and the wreckage of the aircraft was subsequently discovered in a paddock 102 kilometres from the DEPARTURE aerodrome, on the intended track. Investigation revealed that the glider had initially contacted the ground with the leading edge of the right wing, while the aircraft was in a steep nose-down attitude and spinning to the right. There were no known witnesses to the accident, and it could not be established whether the pilot had been attempting to outland or to find a thermal at low level. There was no evidence of any pre-existing mechanical defect which might have contributed to this occurrence. It was probable that control of the glider was lost during a manoeuvre at low speed and height above the ground, however the reason for the loss of control was not determined.

The pilot was conducting the last of his spraying tasks for the day. The paddock had an uphill slope and there were two groups of tall trees at the uphill end. The first run was conducted up the slope but during the subsequent pull up and procedure turn, strong turbulence was encountered. The left wing struck branches in one group of trees, control was lost and the aircraft struck the ground heavily. The fuel tank ruptured, a fire broke out and the wreckage was completely gutted. The spraying was commenced in strong wind conditions and the procedure turn was executed in the lee of the trees. When the turbulence was encountered the pilot banked the aircraft and attempted to fly between the two stands of trees but was unable to prevent the left wing striking a number of branches.

The pilot had been advised that the aircraft propeller was defective and he indicated to witnesses that he intended only to conduct taxying. However, the aircraft was seen to become airborne and start to fly a circuit. On base leg the engine noise grew louder and the aircraft fell to the ground with the rotor stationary. Wreckage examination revealed that part of the propeller had separated in flight and the remaining propeller section had impacted the rotor following failure of the engine mounts due to excessive vibration.

Circumstances:

The aircraft was landing at night on runway 11C, at the end of a multi-sector cargo flight. Weather conditions were fine and clear with a light wind from the north-east. The pilot said the touchdown was normal. However, the aircraft started to pull to the right, the right tyre deflated, and the right main landing gear collapsed. Skid marks on the runway were consistent with the right wheel being locked from about 400 metres beyond the landing threshold. The skid continued for a further 124 metres, parallel to the centreline, before the right tyre deflated. The skid continued for a further 151 metres before the right main landing gear collapsed, resulting in the aircraft departing the runway to the right. A subsequent examination revealed no mechanical fault with the wheel brakes or wheel bearings. Evidence was found which was consistent with an excessive application of the right brake.

After about 80 metres of ground roll following a normal touchdown the nose began to drop, followed by the right and left wings, and the aircraft slid to a halt with the gear retracted. No mechanical fault or defect was subsequently found with the aircraft. The weight of available evidence indicated that the pilot had probably inadvertently selected the gear up shortly after touchdown.

The pilot was conducting his first solo circuit and landing. Following the initial touchdown the aircraft ballooned twice, and the pilot was unable to maintain directional control after the final touchdown. The aircraft collided with another glider which was being prepared for launching. Immediately prior to this particular flight, the pilot had successfully completed a check flight with an instructor. It was considered likely that the aircraft had been affected by a crosswind component during the latter stages of the landing, and the pilot had been unable to react in sufficient time to avoid a collision with the parked glider.

During the first take-off for top dressing operations, the aircraft commenced to swing to the left. The pilot applied opposite rudder and braking but was unable to control the swing. The side loads imposed on the right hand gear caused it to fail at its attachment to the stub wing, and fold up. The left hand oleo strut piston had separated from its cylinder, which then failed at its attachment, and fell from the aircraft. The gear then started to fold back, bringing the piston into contact with the tyre, which gave a braking affect and caused the aircraft to swing. A Transavia Service Bulletin and an Airworthiness Directive require a mandatory inspection to be carried out on all oleo struts of this type after each 100 hours time in service, in order to prevent a failure of this nature from occurring. The aircraft log books could not be located, and it could not be established whether the required inspections had been carried out.