Loss of control

The pilot had arrived at the strip the previous day to continue learning to fly the gyrocopter. He flew one circuit during which the craft was observed to porpoise a number of times. After landing, the pilot complained to his adviser that there was something wrong with the aircraft. The adviser then flew the craft and reported that it behaved perfectly. He counselled the pilot that he was overcontrolling in the pitching plane and suggested flying low runs along the strip as practice to overcome the problem. The pilot did this a number of times and showed good pitch control. On the morning of the accident, the pilot flew some further strip runs, again showing good control. He then began flying circuits at about 50 feet above ground level. On the third circuit, as the gyrocopter was turning base with about thirty degrees bank applied, the following sequence occurred in rapid succession - nose pitch-up 15`, nose pitch-down 20`, nose pitch-up 40`, nose pitch-down 50`. The gyrocopter remained in this latter attitude until ground impact. Although the pilot had owned the gyrocopter for some six months, he had flown it only once previously. This was some six weeks before the accident when other instances of pitch control difficulties occurred. There was no evidence of any fault with the gyrocopter. The engine sounded normal up to the time of impact and the shattered propeller blade was evidence of the engine being under power at impact. The gently undulating terrain over which the craft was seen to fly might have given the pilot the illusion that he was descending as he flew the base turn. The porpoising of the gyrocopter as described by witnesses was indicative of the pilot overcontrolling in the pitching plane. When the craft pitched nose down the second time, the airflow through the rotor disk would have been reversed from the normal upwards flow to a downwards flow. Once this condition arises, recovery to normal flight is impossible. It was noted during the investigation that there was no part of the gyrocopter in the pilot's normal forward field of view which could assist him in judging the in-flight attitude of the craft. Such information is particularly important for control in the pitching plane, especially during the learning phase.

The glider was launched by being towed behind a motor vehicle. After the glider became airborne, the pilot signalled to the vehicle driver to slow down. The vehicle driver slowed the vehicle too quickly, the tow rope slackened and the rope drogue deployed. The tow rope then released from the glider. Because of the position of the tow rope, below the glider, the pilot did not immediately lower the nose, the glider stalled at about 15 feet agl and landed heavily.

The owner/pilot had been designing and building ultralight aircraft for a number of years. This particular aircraft had been designed for a nosewheel landing gear system, however after flying the aircraft the pilot decided that he did not like this particular configuration. He decided to modify the aircraft to a tailwheel design, and had spent a considerable time over the preceding weeks on the rebuilding program. After completing the work the pilot was forced to wait for several days for suitable weather conditions in which to carry out the first flight. On the morning of the accident the pilot carried out a pre-flight inspection before taxying to the end of the strip in use. He was observed to exercise the controls prior to commencing the take-off. The aircraft became airborne after a ground run of about 125 metres, and the angle of climb was seen to progressively increase. At a height of about 80 feet above the ground the left wing dropped and the aircraft dived steeply to the ground. An inspection of the wreckage revealed that the ailerons had been incorrectly designed and were operating in the reverse sense. It was considered possible that the pilot may have been momentarily confused when the aileron response was not as expected, and may not have noticed the steepening nose attitude in time to take corrective measures. In this design the pilot sat in a totally exposed position at the front of the aircraft, and had only limited pitch references. The pilot had not flown a totally open cockpit aircraft for some considerable time, and was not wearing goggles. Apart from the aileron problem no other faults were found during the investigation. During his pre-flight checks the pilot had evidently not detected that the ailerons operated in the reverse sense.

The pilot was returning from a flight to the local training area and following a normal approach to land into wind, he flared the aircraft for a wheeler landing. During the landing roll the tail wheel was held off the ground until elevator control became ineffective. Before the tailwheel contacted the ground, the pilot relaxed his attention and the aircraft commenced to swing to the right resulting in a ground loop. The left main landing gear oleo fractured and the left wing impacted the ground. There were no pre-existing defects with the aircraft which could have contributed to the accident.

On completion of a lengthy pre-flight inspection of the aircraft and engine warm up, the pilot taxied the aircraft for DEPARTURE from runway 18. The take off roll was commenced following the application of full power, with the aircraft held on the brakes. After rolling approximately 150 metres the aircraft veered to the left and developed a skid before straightening as it left the runway. Shortly after leaving the runway the aircraft pitched nose up and became airborne for a short distance before impacting the ground. No defect was found which could have contributed to the pilots inability to maintain directional control of the aircraft during the take off roll. The reason for the loss of directional control during the take off roll could not be determined. It is considered that the failure of the pilot to abandon the take off prior to the aircraft leaving the runway contributed to this accident.

The pilot decided to carry out a low fly past along the strip to check the effect of the prevailing strong wind. After having flown along about a third of the strip he landed the aircraft. During the landing roll the wind lifted the left wing and the aircraft began to move off to the right of the strip. The right wheel struck a low dirt mound and was twisted rearward. The aircraft then ran through a fence before coming to rest. The particular strip is an agricultural ALA, with a length of 490 metres and restricted to one-way operations. The pilot was familiar with the strip, having landed there on numerous occasions. The first part of the strip was protected from the wind, and on encountering virtually calm conditions, the pilot had made a spur of the moment decision to land. Shortly after touchdown the aircraft had left the protected area and was subject to a strong and gusty wind.

The pilot had been undergoing a course in aerobatic flying. After completing 11.5 hours of dual aerobatic instruction, she had been authorised to carry out her first period of solo aerobatic manoeuvres. She was briefed to carry out two spins, followed by other basic manoeuvres, consisting of loops, stall turns, rolls and wing-overs. The aircraft was to operate in the designated training areas. About 8 minutes after the pilot reported entering one of the training areas, the aircraft was observed to be at a relatively low height, spiralling in a clockwise direction. Shortly afterwards it struck a group of large trees and dived to the ground. The damage sustained was consistent with a relatively high speed impact. No fault was subsequently found with the aircraft or its systems which might have contributed to the apparent loss of control. It is not known which manoeuvre the pilot was attempting at the time, but assuming that the briefed sequence was being followed, it is likely that the loss of control occurred during the spinning sequence. The factors leading to the development of the accident have not been determined.

The instructor was landing the aircraft in a crosswind from the right. As the speed reduced, during the landing roll, the aircraft began to veer to the right. The instructor applied full left rudder and brake in an attempt to maintain directional control, but the aircraft continued to veer off the strip. Being concerned that the aircraft would strike a fence and overturn, the instructor applied full power in an attempt to clear the fence and land in an adjoining paddock. The aircraft cleared the fence but subsequently stalled and was blown back against the fence.

The pilot was conducting a short cross country flight. As he approached the end of the final leg he realised that there was insufficient height available for the aircraft to make a safe landing at the destination aerodrome. A decision was made to attempt an out-landing as the aircraft passed through 1200 feet on the descent. At that height the choice of fields was restricted and the one that was chosen for the landing was unsuitable. The landing area was covered with long grass and sloped downwards and from right to left. A shallow gully also crossed the area. During the final stages of the approach the right wing touched the ground and long grass causing the aircraft to yaw violently and enter a ground loop. The aircraft finally touched down whilst it was travelling sideways and it came to rest after travelling backwards along the paddock. The pilot was not authorised to conduct cross country flights in the particular aircraft type as he had not completed the required number of flight hours and landings. This accident was not the subject of an on scene investigation.

Circumstances:

On the day of the accident, the pilot took three of her work colleagues on a tour of the mine pits to the North of the camp. When the aircraft returned to the mine's airstrip, the pilot made a low pass over the camp with the canopy fully opened to drop water bombs, before commencing a climbing left turn to rejoin the circuit for a landing. Whilst the aircraft was climbing, the aircraft stalled. The pilot could not regain control before the aircraft collided with the trees. The pilot had been previously instructed not to make low passes over the campsite. The aircraft flight manual indicates that flight with the canopy partly open, but not fully open, is permissible. The effect of a fully opened canopy on the aerodynamics of the aircraft was not determined. The pilot apparently failed to ensure that she maintained a sufficient margin above the stalling speed during the climb out following the pass. This accident was not the subject of an on-scene investigation.

Significant Factors:

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

1. The pilot ignored previous instructions not to make low passes over the campsite.

2. The pilot operated with the aircraft canopy fully open, which may have affected the performance of the aircraft.

3. The pilot failed to maintain adequate airspeed.

4. There was insufficient height available for the pilot to recover before the aircraft collided with the trees.