Loss of control

Circumstances:

The pilot landed the aircraft on a strip near the lake and visited a group of friends on the shore with his passenger. It was arranged that the pilot would return in the aircraft and fly past for some photographs to be taken. The first run past the group on the shore was made in an easterly direction. The aircraft was then seen to turn onto a westerly heading and position for a second flypast. The height of the aircraft above the water on the two passes was estimated to be about 60-80 feet although photographs of the event show it to be much lower. After passing over the observers on the last run, the aircraft was seen to turn towards the east and start a steep climb. Witnesses reported that the speed of the aircraft reduced rapidly, and, at about 150 feet above ground level, the engine noise apparently reduced or stopped. The aircraft then dropped the right wing and dived into the water. The aircraft was seen to sink rapidly and only the passenger extricated himself from the wreckage. He clung to the tail and was recovered quickly by rescuers in a power boat. Despite repeated dives, the pilot could not be reached, and his body was removed after the wreckage was towed to shore. Detailed investigation did not reveal any faults or anomalies in the aircraft which could have contributed to the accident. Damage to the propeller was consistent with a strike under power. It is considered that the reduced power at the top of the steep climb was pilot induced during the attempted execution of a stall turn type manoeuvre. Discussions with witnesses and club members revealed that the pilot was overconfident in his attitude to flying the ultralight and would not readily accept advice or counselling on his handling the aircraft. It was further revealed that the pilot was prepared to perform in front of an audience and the events on the day of the accident support the conclusion that the pilot was engaged in an impromptu display in front of friends at the lake shore.

Significant Factors:

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

1. The pilot engaged in an impromptu flying display for friends.

2. The pilot attempted a manoeuvre at an altitude that provided insufficient height for recovery.

3. The pilot was probably complacent and overconfident in his ability to handle the aircraft.

Circumstances:

The aircraft was scheduled to conduct three round trips between Townsville and Cape Richards, with a stop at Orpheus Island on some legs, during the day. The pilot involved in the accident flew the first and third trips and another pilot flew the second. After the first trip the pilot reported that he pumped the floats out and considered that the quantity of water removed was normal. On the third trip he picked up a "standby" passenger at Orpheus Island. On arrival at Cape Richards the scheduled six passengers were loaded. A witness employed by the resort to handle the aircraft and passengers on the island reported that the floats appeared to be sitting in the water such that the water was above the normal water line on the floats. Examination of the aircraft loading indicated that the aircraft was overweight, and the centre of gravity was just inside the rear limit. The pilot reported taxiing at 1613 hours with eight persons on board. At 1624 hours he reported that he was returning to unload one passenger. In that time two take-off attempts into the north-east were made. The wind in the bay where the attempts were made was a light northerly. The pilot again reported taxiing at 1634 hours with seven persons on board. A further two take-off attempts were made. On the final attempt the pilot did not taxi as far into the bay as on previous occasions. The take-off was continued well out beyond the shelter of the island into an area where the wind was easterly at about 10 knots, and the swell was 1 to 1.5 metres. The pilot reported that the aircraft had attained an indicated airspeed of 55 knots, and he intended to fly it off the water at 57 knots. The right float had lifted from the water, and it hit a wave which pushed the right wing up. The pilot was unable to lift the left wing which hit the water, causing the aircraft to cartwheel.

Significant Factors:

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

1. The pilot selected the incorrect take-off direction for the wind conditions prevailing.

2. The pilot continued the take-off into an area of unsuitable swell. This accident was not the subject of an on-scene investigation.

The student glider pilot had carried out three previous flights during the day. Her instructor had informed her that she was at a suitable stage of training to be introduced to practice emergency procedures. After sighting her training log book, the instructor for the final flight left the glider to speak to the pilot of the tug aircraft. The instructor returned to the glider and preparations for take-off were then continued. Witnesses observed that the tug and glider became airborne and subsequently carried out normal turns to position the aircraft on a downwind leg at about 500 feet above ground level. The tug aircraft was then seen to waggle its wings sharply three times. Almost immediately this aircraft assumed a steep nose-down attitude, its tail apparently being pulled into a vertical position by the tow rope which was still attached to the glider. The glider then also assumed a steep nose-down attitude and both aircraft spun or spiralled towards the ground. The tow rope was released from both aircraft, but neither pilot regained control before impact with the ground. The subsequent investigation did not disclose any defect or malfunction with either aircraft that might have contributed to the development of the accident. During glider towing operations when the pilot of the tug waggles the aircraft wings it is a signal to the glider to immediately release from the tow. This "wave-off" signal would normally be given when the tug pilot detects some malfunction or when the glider is sufficiently far out of position behind the tug to affect the tug pilot's control of his aircraft. On this occasion it was considered possible that the instructor in the glider had arranged for the tug pilot to simulate an emergency by giving a wave-off signal. The wave-off signal was observed to be given in the normal position relative to the strip for such training manoeuvres to be performed. The reason for the subsequent loss of control of both aircraft could not be determined, however it was evident that when the aircraft released the tow rope there was insufficient height remaining to permit recovery to normal flight.

Upon arrival at Mitta Mitta the pilot performed a touch and go on the 1000 metre long gravel strip, before approaching for the full-stop landing. After touchdown, the aircraft veered to the right but was repositioned on the centreline within a short distance. However, it again veered to the right and departed the hard packed gravel surface of the strip and entered an area of long, damp grass. The pilot was unable to control the direction of travel and the aircraft encountered a drainage ditch, an earth mound and a fence before coming to rest with its noseleg collapsed. No fault was found with the aircraft systems that may have contributed to the accident. The pilot had not flown the aircraft for 18 months and it is probable that the veer was caused by differential braking in combination with the damp, slippery grass on the sides of the strip. Weather conditions were fine and calm and were not considered a factor.

At the conclusion of a local flight the pilot carried out a practice touch and go landing, and then positioned the aircraft for a full stop landing. Wind conditions at the time were light. Shortly after touchdown the aircraft commenced to veer to the right. The pilot was unable to stop the swing, and elected to go around. However, the aircraft was no longer aligned with the strip and during the attempted go-around the aircraft struck an embankment and a small tree. The pilot closed the throttle and the aircraft came to rest about 100 metres to the right of the strip.

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.