Circumstances:

The pilot reported that he had landed to assist two persons on the ground and had taken off with one of them on board. When at about 200 feet above ground level.

Circumstances:

As the aircraft slowed after a normal landing the right main landing gear and then the left main landing gear collapsed. The aircraft skidded to a halt on the fuselage underside. Examination of the broken section from the right landing gear strut showed that overload failure had occurred around a welded joint, inboard of the suspension bungee attach point. The investigation has shown that the aircraft manufacturer had previously identified a problem with the strength of the tubing being used in this section of landing gear. The manufacturer advised that an interim modification had already been incorporated on the aircraft production line, which increased the wall thickness of the tubing. In the longer term, it was proposed to modify the strut design to increase its strength.

At about 300 feet agl on climb out, the pilot heard a loud bang and saw that the propeller had separated from the aircraft. He lowered the nose to regain airspeed but the aircraft descended steeply and landed heavily in a rice paddy. The engine crankshaft counterweights were found to be worn and detuned. The resulting vibrations were transferred to the propeller hub, which failed and released one of the blades. This type of detuning usually occurs as a result of large and rapid power variations, and as this aircraft was used for agricultural operations it is likely that the work requirements precipitated the failure.

During cruise at about 1000 feet agl the engine began to run roughly and the pilot observed falling oil pressure indications. A severe engine vibration then developed and the pilot, after selecting a suitable forced landing area, shut down the engine. He delayed lowering the landing gear until he was satisfied that the selected area had a firm surface. The gear was selected down on very late final, but only the nose gear had time to become partially extended before touchdown. Lack of sufficient tension of a nut securing a conrod bolt of Number 1 cylinder allowed the conrod bearing cap to loosen causing loss of oil pressure and subsequent engine failure.

Circumstances:

There was a strong easterly wind blowing when the pilot landed. After landing he left the main rotor drive engaged and did not secure the collective control with the latch that was provided for that purpose. A sudden gust of wind caused the collective pitch, on the main rotor blades, to increase and the aircraft lifted off. The pilot regained control of the helicopter, but he was unable to avoid colliding with a tree.

After helping to herd cattle to a yard, the pilot turned the helicopter and accelerated away adjacent to a creek. The helicopter struck a powerline, which crossed the creek at right angles, and impacted the ground on its right side. One of the main rotor blades bounced backwards into the cabin and almost severed the pilot's right foot. The powerline was difficult to see against the background of the surrounding countryside. The pilot, who has no memory of the accident, was aware of the location of the powerline but now believes he must have temporarily forgotten about its presence.

The pilot said that he was flying the aircraft at 350 feet above the ground when the engine stopped suddenly. During the glide to earth, he carried out carburettor icing clearing procedures, switched the electric fuel pump on and attempted two engine starts, all to no avail. During the subsequent ground roll, the pilot was unable to avoid collisions with trees and an anthill. After the dust settled, he attempted an engine start which was successful. The reason for the engine stoppage has not been determined.

The pilot decided to carry out a circuit in order to check the performance of the engine. Because of the presence of a gusting 20 knot westerly wind, a higher than normal approach speed was flown. The pilot stated that he closed the throttle at about 50 feet agl and flared the aircraft. The subsequent landing was heavy, the aircraft bounced, the pilot moved the control column forward and the aircraft bounced a second time. On the third touch down the pilot reported that the tail struck the runway causing substantial damage to the tail area of the aircraft.

While returning to refuel at a mustering yard, the pilot attempted to move a bull from some trees. When this proved unsuccessful the pilot climbed to continue the flight to the yard. The engine began to run roughly and an approach to a clearing was made. Rotor rpm decayed as some trees were cleared and the pilot was unable to prevent a heavy landing. The helicopter bounced about two metres, the right skid collapsed and the main rotor struck the ground. Investigation revealed that the engine failed due to fuel exhaustion. The pilot's technique was to work on a set endurance from full tanks and not rely on the fuel gauge. At the previous refuelling he filled the tank to the filler neck, but the helicopter was parked on a slope which prevented approximately 20 percent of the tank's volume from being used, and reduced the endurance.

Circumstances:

The pilot reported that he made a normal approach to land on a large claypan. As he raised the nose to enter the hover prior to touching down, the tail rotor struck the ground, and the pilot was unable to prevent the aircraft from rolling over.