Circumstances:

After flying to the resort, the pilot landed the helicopter and picked up a photographer for local area photography. He reported that the initial runs were flown at 500 feet above ground level. During some of these runs the wind changed in direction from north to east and was about 10 knots in speed. The pilot noticed on some occasions, when the wind was a tailwind, it caused control difficulties. On one pass, at about 200 feet above the ground and travelling forward at about 30 knots, the helicopter was again affected by a tailwind. The pilot was unable to prevent it yawing to the right. The rotor rpm decayed, collective was lowered, and the aircraft was flared at about 100 feet, but the sink rate could not be arrested. The helicopter struck the ground at a high rate of descent but remained upright. Evaluation of the flight indicates that the pilot was flying very slowly with a tailwind. He lost directional control, and insufficient power was available to sustain rotor rpm. The pilot later flared the aircraft too high to enable a landing at a safe rate of descent.

Significant Factors:

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

1. The wind was variable in direction.

2. The aircraft was being operated at slow speed and with a tailwind.

3. The pilot lost directional control.

4. The pilot misjudged the height to begin the flare for landing. This accident was the subject of an on-scene investigation.

Circumstances:

The aircraft was on its first flight at the time of the accident. All engine parameters had been normal during extensive ground testing and immediately prior to take-off. The aircraft was in a turn at 600 feet after take-off when the engine began to run roughly. The pilot commenced an approach for a forced landing in a paddock which appeared to be suitable. However, just prior to touchdown he observed a ditch running across the paddock. He attempted to clear the ditch, by raising the nose, but the right wing dropped. The right mainwheel struck the ground and was torn off, causing the aircraft to settle into the ditch and overturn. An inspection of the engine indicated that some of the cylinder head retaining bolts were not torqued correctly. In addition, the spark plug in the left rear cylinder had been inserted with a crossed thread and was not seating correctly. The centre electrode of this plug has been destroyed. There was damage to both the cylinder head and the exhaust valve seat and there were indications that combustion gases had been blowing past the poorly seated spark plug and the closed exhaust valve. Ceramic deposits, from the missing electrode, were found in the cylinder and the exhaust port. The engine had been purchased and installed as a correctly certified zero-time unit, although the spark plugs had been removed and replaced prior to the flight.

Significant Factors:

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

1. The procedures used during assembly of the engine and installation of the spark plugs were inadequate.

2. The partial loss of engine power, resulting from damage caused by the incorrect assembly, forced the pilot to carry out a landing on unsuitable terrain.

The balloon operator had arranged a familiarisation flight for visiting travel agents. After some low and higher level demonstrations, the pilot descended the balloon to drift at treetop level above the Todd riverbed. As he was aware of powerlines in the vicinity he elected to land on a clearing just ahead. The pilot activated the rip panel which resulted in a high descent rate and very hard landing. The pilot became committed to the landing on unsuitable terrain after choosing to descend too early. The pilot of another balloon, that had been operating in company with this balloon, had delayed his descent a short time and made a successful landing on an open area. This accident was not the subject of an on-site investigation.

Circumstances:

The helicopter was flying at about 25 knots and a height of about 75 feet, 10 feet to the left of power lines. The passenger was surveying the wires. As the helicopter approached a tree line, the pilot increased collective. However, rotor RPM decayed, and the helicopter descended rapidly, hitting the ground and rolling over.

Significant Factors:

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

1. The pilot overpitched the main rotor, resulting in a loss of rotor RPM.

2. Insufficient height was available for the rotor RPM to recover before the helicopter struck the ground.

Circumstances:

The pilot reported that the engine stopped suddenly at about 120 feet during initial climb. As there was insufficient altitude to return to the strip, an emergency landing was effected into a near-by paddock. Investigation determined that the flexible rubber induction ducting had detached and been sucked into the carburettor box blocking off the air supply to the carburettor.

At the conclusion of an aerobatic flight, the pilot intended to practice a number of circuits and landings. Two touch-and-go landings were completed, and the pilot positioned the aircraft for a full-stop landing in 10 knot crosswind conditions. Towards the end of the landing roll, the aircraft commenced to ground loop to the left. The pilot applied corrective rudder and brake, but was unable to arrest the swing. He then applied full power, with the intention of becoming airborne and passing between trees which lined the side of the strip. The aircraft lifted off, but then collided with a tree, fell to the ground, and came to rest inverted. The particular type is known to be difficult to control directionally. It was considered possible that the pilot had relaxed his concentration after the aircraft had touched down.

Circumstances:

During the flight over the Simpson Desert, the pilot realised that the ground features were difficult to relate to his map. Large areas were covered in flood waters which distorted the usual ground features. While still outside the 40 nautical mile rated coverage of the Birdsville Non-Directional Beacon.

The pilot was carrying out a period of circuit practice. After touchdown on the fourth circuit the aircraft commenced to porpoise. The pilot applied forward elevator in an attempt to control the aircraft. The aircraft subsequently touched down heavily on the nosewheel, causing the nosegear to collapse and the propeller to strike the runway. The pilot lacked recent experience, and had not considered going around when the aircraft began to porpoise.

One of the pilots was undergoing practice in engine failure emergencies at night. The helicopter was equipped with a "Nightsun" light, which was used to illuminate the ground below the aircraft. Fixed lights were also installed at the edges of the helipad. During the third practice autorotative descent, the Nightsun light was inadvertently extinguished when the aircraft was about 300 feet above the ground. It was turned on again by the time the aircraft had descended to about 100 feet, and the remainder of the descent and flare appeared to be normal. However, after touchdown the aircraft became airborne again, before touching down on the heels of the skids while moving slowly forward. The aircraft rocked forward and the main rotor severed the tail boom just forward of the tail rotor assembly. The surface of the helipad had been softened by recent rain ,allowing the heels of the skids to dig in slightly. This probably accentuated the rocking movement which led to main rotor blade contact with the tail boom. The type of manoeuvre being performed requires a high level of skill. Should a slight error of judgement occur, there is little opportunity for any corrective action to be successful.

Circumstances:

The pilot reported that when he selected the landing gear up after take-off, it remained down, and the three green lights remained illuminated. After checking the circuit breakers, several more attempts were made to retract the landing gear without success. During the subsequent landing, the landing gear collapsed, and the aircraft settled onto its underside. The only fault revealed during examination of the landing gear system was varying resistance in the right landing gear safety switch (the squat switch). This intermittent fault could have prevented the landing gear from retracting. The pilot reported that he conducted a smooth landing because of the nature of the problem. Despite that, it could have been sufficient to free the switch and allow the retraction cycle to begin as the oleos were compressed but before the safety switch was made. However, this could only have happened if the landing gear selector was in the up position.

Significant Factors:

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

1. There was varying resistance in the right landing gear safety switch causing intermittent operation.

2. The aircraft was landed with the landing gear selector in the up position.