Loss of control

Circumstances:

The pilot reported that he was making his first flight in his ultralight which he had just completed building. After a 30-minute flight around his farm he made a landing approach to a grass strip. The intention was to overfly the strip and make a left circuit. However, as he crossed the threshold, he judged that he was in the right "slot" for a landing and the approach was continued. But when the aircraft was in the flare, he sensed the heading to be 10 degrees right of the strip direction. Because of lack of recent flying experience, he decided at that point that the safest thing to do was to abandon the landing attempt and go around. Confident that he had plenty of reserve power he did not use full throttle for the go-around. As power was applied, the right wing dropped gently, not responding to aileron. The pilot assumed a control malfunction and was not prepared to open the throttle any further. The aircraft continued to turn to the right, now heading toward a power line that was running parallel to the landing strip. The pilot instinctively applied backstick to clear the power line, but the aircraft continued the uncontrolled gentle turn to the right. The pilot said that "resigning himself to the inevitable" he began closing the throttle. The aircraft gently descended into a stubble paddock. The pilot advised that he later realised that a mild stall had developed on the right wing and had proper stall recovery technique been applied, the situation would have been corrected. The pilot subsequently critically self-analysed the accident and identified a number of factors that resulted in him being under significant stress while performing this first flight in his aircraft. In hindsight he believed that he should not have flown the aircraft at all until he had completed some dual flying.

Circumstances:

The pilot stated that after becoming airborne he lowered the nose of the aircraft to gain airspeed, but the aircraft sank back onto the water, then veered to the left. The pilot closed the throttle and attempted to steer the aircraft away from the riverbank. The floats struck a rock retaining wall and the aircraft nosed over. The take-off attempt was towards the lee of trees near the riverbank. The local wind conditions produced approximately five knots of crosswind component from the right. The aircraft may have encountered a sudden decrease in headwind component during the take-off causing it to sink back onto the water. Loss of directional control may have occurred because the aircraft was not correctly aligned at touchdown.

FACTORS

1. The aircraft sank back onto the water after becoming airborne possibly due to an unexpected wind gust.

2. The pilot was unable to maintain directional control after the aircraft touched the water.

After completing a dual instruction period of crosswind take-offs and landings the pilot prepared for solo exercises in the training area. At about 45 knots during the take-off roll the aircraft unexpectedly became airborne. The pilot had been correcting for the left crosswind and when the aircraft touched down again its heading altered sharply to the left. Attempts to regain control were unsuccessful and the pilot abandoned the take-off. Damage to the nosegear was sustained when the aircraft entered a ditch before coming to rest off the side of the strip. The wind at the time of the attempted take-off was gusting close to the crosswind limit for the aircraft type. After the aircraft ran off the strip, soft wet ground reduced braking effectiveness, and the pilot was unable to prevent the entry into the ditch.

The pilot, who was an experienced glider pilot and instructor, was taking part in a gliding competition. Only 2 of the 12 competitors were able to complete the exercise, the remainder being required to outland. Almost 4 hours after being launched, the aircraft was sighted in a right hand circling descent, apparently being manoeuvred for an outlanding. At low level, the angle of bank was seen to suddenly increase and the nose dropped. The right wing struck the ground and the aircraft cartwheeled before coming to rest about 34 metres from the point of initial impact. It was evident that the aircraft had entered an incipient spin at too low a height above the ground to enable the pilot to recover control of the aircraft. The reason for the loss of control could not be determined.

The pilot was attempting to complete a solo flight of at least one hour duration as part of the qualification for the issue of a C Gliding Certificate. Witnesses reported that during the winch launch, the glider lifted off too early, and then assumed the climb attitude before sufficient airspeed had been obtained. The pilot stated that she released from the winch cable when she became aware that the airspeed was too low. At about the same time the right wing dropped and the aircraft turned through about one and a half revolutions before impacting the ground with the right wingtip. The pilot had attempted to correct for the wing drop with aileron control inputs, which were ineffective at the low airspeed.

The pilot and passenger were undergoing a full time flying training course to Commercial Licence standard, and had both recently obtained their restricted Private Pilots Licences (i.e. restricted to flight within the flying training area). On the day of the accident the pilot had spent the morning at lectures, and preparing for navigation exercises. After lunch he approached the Chief Flying Instructor and asked if he could take VH-FLF to the training area for an hour. This was approved and the pilot signed the flight authorisation sheet and entered the time 1340 hours on the sheet. There was no indication on the authorisation sheet that he intended to take a passenger, nor did he mention this to the Chief Flying Instructor. The pilot was later seen sitting in the aircraft, apparently awaiting the arrival of his passenger. There appears to have been no prior arrangement, other than a spur of the moment decision by the passenger, to go on the flight. The pilot called Archerfield Tower at 1351 hours and reported taxiing for the southern training area. At 1359 hours VH-FLF was cleared for takeoff. This was acknowledged by the pilot, and no further radio transmissions from the aircraft were heard or recorded. At approximately 1415 hours, witnesses heard the aircraft flying overhead. The aircraft was seen flying in a south-easterly direction in apparently normal flight, when the engine noise suddenly ceased. The aircraft was then observed descending in a steep spiral or spin from a altitude of about 2000 feet. The spiralling motion appeared to cease momentarily before the aircraft dived into the ground. The aircraft impacted the ground in a steep inverted nose down attitude. Indications are that the aircraft may have been recovered from the spiral briefly, before stalling and becoming inverted during the recovery at a very low height. No mechanical defects were found which may have affected the airworthiness of the aircraft, or which may have contributed to the development of the accident.

As the pilot rotated the aircraft for takeoff he heard several bangs and felt there was an accompanying power loss, so he aborted the take-off. When it appeared he would be unable to stop in the strip remaining he deliberately ground looped the aircraft. The nosewheel leg was damaged and the propeller struck the surface of the strip, necessitating an engine strip - the propeller was not damaged. An inspection of the aircraft did not find any fault with either the engine or the braking system. The blacksoil strip was found to be very soft and it is considered that the retarding action of the strip caused the pilot to believe a power loss had occurred. The bangs heard by him were probably caused by clods of dirt hitting the fuselage.

During circuit training, the aircraft suffered a complete engine failure. The pilot was unable to reach the flight strip and landed the aircraft amongst trees. One of the two pistons of the two stoke engine had seized in the cylinder, probably due to lack of lubrication.

Circumstances:

The pilot was carrying out a survey flight of his property to locate a vehicle. The aircraft was observed by ground witnesses, near the vehicle, to commence a descending right hand turn with the apparent intention of landing in a cleared paddock adjacent to the one in which the vehicle was located. The aircraft appeared to lose altitude suddenly after it had completed about 270 degrees of the turn and the right wing touched the ground. The aircraft cartwheeled to a stop. The pilot survived the accident but is unable to remember anything about it. It is probable that the pilot was concentrating his attention on either the ground party or the intended landing area and he allowed the aircraft to either stall or unintentionally lose height. The wing struck the ground before the pilot was able to take action to recover the aircraft to level flight.

Significant Factors:

The following factor was considered relevant to the development of the accident:

1. Possible pilot distraction leading to loss of control and ground impact.

The aircraft was observed to head in a northerly direction after take-off. About 20 minutes later, the witness saw the aircraft, which was flying at an altitude of about 80 feet, returning. As he watched, the aircraft appeared to turn to the right and roll inverted, before disappearing behind trees and buildings. The aircraft struck the ground in a steep nose down attitude. The aircraft impacted the ground at about the base turn position. An inspection of the aircraft did not reveal any fault which may have contributed to the occurrence.