Loss of control

The Cherokee II type of glider is of plywood construction and accommodates only one occupant. Miss Sainsbury had made only one previous flight in the type some months previously and, on that occasion, she released the tow cable during the launch because of excessive winch speed. She subsequently made a satisfactory landing. On the day of this accident she completed a satisfactory check flight with an instructor in a two-seat glider this flight included a simulated cable break during the winch launch at a height of some 400 feet. The weather was fine and clear, the wind was light and from the north-west, the air temperature was about 30°C. In preparation for her flight in VH-GRD, she was briefed regarding the operation of the glider by her father, who is an experienced glider pilot and was to operate the winch for the launch. She then seated herself in the glider and fastened her restraining harness and, while her father was preparing the tow cable and winch for operation, she was further briefed by the instructor who had accompanied her on the check flight. The glider was then launched into the west and, initially, appeared to be operating normally. However, at a height of about 600 feet it appeared to be climbing in a nose high attitude at a slower than normal speed. The port wing then lowered, a turn to the left commenced and the tow cable released from the glider. The turn developed into a spin and, after two complete turns, the rate of spin appeared to decrease momentarily but it then resumed and continued until the glider struck the ground in a steep nose down attitude.

The recent experience of the pilot had been acquired in a Piper PA28-235 aircraft owned by the company with which he was associated. He had not previously flown the Cessna 177 model but this type was included in a group of aircraft endorsed on his licence. Before the flight he was briefed by the owner on the handling characteristics of the aircraft and after normal pre-flight preparation, he and the passenger boarded the aircraft and taxied to the 334 degrees strip. Conditions at the time were hot and moderately gusty with the temperature about 90 degrees F and a north westerly wind of 8 to 12 knots. After checking the engine performance the pilot was not satisfied with the operation of the carburettor heat control and taxied back to the apron. The aircraft owner reassured him of the serviceability of the system and the pilot again taxied to the 334 degrees strip from which, after a further check of engine and flight controls, the aircraft took off. After becoming airborne, the aircraft assumed what appeared to be a normal climb straight ahead, but at a height of 100 to 150 feet it began a turn to the left with an angle of bank of about 15 degrees. The turn continued through approximately 110 degrees then the nose suddenly dropped as the angle of bank increased and the aircraft, still turning, dived to the ground. The passenger was able to escape from the cabin before the wreckage was destroyed by fire, but was prevented by the flames from giving effective assistance to the unconscious pilot.

The aircraft was to land at a newly constructed airstrip near the camp of a survey party. At a previous stop the pilot was given some details of the size of the strip and he assessed it as suitable for the aircraft type. The aircraft was flown to the strip empty, the pilot made an in flight inspection and a normal landing. After landing, it became obvious that the width of the strip was below the minimum specified for safe operation and that the surface was very soft. From the southern end the strip rose 20 feet in 2000 feet and immediately beyond this crest curved 7 degrees to the right. The pilot warned another aircraft of the company of conditions at the strip and advised the pilot to divert to a nearby aerodrome. He refuelled the aircraft and then prepared to take off into the north using approximately 2000 feet of the northern end of the strip in a cross wind of 10 to 15 knots from the right. The take off began slightly to the left of the strip centre line and the aircraft became briefly airborne at the crest at a speed of about 70 knots. The aircraft sank back to the ground and because of the change in direction of the strip at that point and the influence of the cross wind, immediately ran off the strip to the left. The aircraft tracked over scrub and rough ground until the nosewheel struck a rocky outcrop and collapsed. The aircraft came to rest 365 feet left of the centre of the strip and 215 feet beyond the northern end.

The aircraft stood overnight in the open at the station airstrip ready for an early morning take off. In a daily inspection made soon after first light, the pilot found that a heavy dew had left beads of moisture covering the aircraft exterior. This was cleaned off the windscreen, which was also misting internally. After a normal warm up and ground test the pilot cleaned the inside of the windscreen and lined up for take off. At this time forward vision was somewhat obscured but the pilot anticipated that outside condensation would clear as the aircraft gathered speed. The take off was commenced but the pilot found that the windscreen did not clear as expected and when full power had been applied and at a speed of about 50 knots, moisture blowing back off the nose of the aircraft caused almost complete loss of forward vision. Finding that the aircraft was moving to the left side of the strip the pilot closed both throttles to abandon the take off and attempted to brake to the right but was too late to prevent the aircraft from swinging left off the strip. The wings were damaged by impact with small trees and the aircraft groundlooped to the right and skidded to a halt. The passengers left by the normal exit and there was no fire.

The aircraft was engaged on a local sight seeing flight and the gross weight of the aircraft was close to the maximum permitted. The only previous occasion on which the pilot had flown a fully laden aircraft was during a check by his instructor on 21st December, 1969 at which time flying conditions were good. The pilot elected to take-off on the 03 strip into a light north easterly wind. During the take-off the pilot noticed that the wind had become gusty. When the airspeed had reached about 50 knots the aircraft became airborne and shortly afterwards the pilot heard the stall warning horn sound. He lowered the nose to increase speed but soon thereafter he raised the nose of the aircraft to climb, the stall warning horn again sounded and the aircraft veered and began a turn to the right as the right wing dropped. The pilot attempted to continue the turn to land back on the aerodrome but, when he believed that he was losing control of the aircraft, he attempted to level it and reduced power preparatory to letting the aircraft settle in light scrub. The aircraft stalled from a height of about 25 feet with the right wing striking the ground first.

After flying northward and examining surface mineral characteristics from the air the pilot decided to return to Bandya Homestead where, on circling the 300 feet wide earth strip, he judged the wind to be directly across it and gusting between 10-15 knots. He selected full flap and approached to land, Intending to touch down firstly on the left mainwheel and with the left wing lowered. The aircraft touched down on the left main wheel close to the centre of the strip and the nose wheel and right main wheel then quickly made contact. The aircraft ran straight and parallel to the edge of the strip for 350 feet, with the left wheel intermittently lifting, but it then commenced to veer to the left at an increasing rate. Despite the application of right rudder and the late use of brake the aircraft continued to swing and finally ran off the left hand edge of the strip and the nose wheel struck a low ridge of earth. The nosewheel assembly collapsed and the aircraft came to rest on the main wheels and lower engine cowling.

The pilot, an enthusiastic light aircraft owner, had organised a week end "fly in" to his airstrip at Devon Downs, which was attended by light aircraft pilots and parachutists together with their families and friends. During the day a programme of general flying was carried out and late in the afternoon the pilot flew to nearby Scrubby Flat with the two passengers to pick up some sleeping bags. The passenger in the right hand front seat was also a qualified pilot but the right hand control column had been removed earlier in the day to permit parachute dropping and had not been replaced. The people assembled at the airstrip at Devon Downs first sighted the aircraft on its return as it climbed up from the nearby Murray River valley which, in this area, is bordered by 200 feet high cliffs. The aircraft then made a shallow descent and flew along the strip on a heading of about 250 degrees, at a very low height. At the western end of the strip the aircraft pulled up steeply to between 200 and 300 feet above the ground and began a "wingover" turn manoeuvre to the left. As the turn progressed to the point at which the wings were steeply banked and the fuselage approximately horizontal, the spectators saw the aircraft falter, then the nose dropped and the aircraft dived into the ground at a very steep angle. A fierce fire broke out immediately on impact and the aircraft was completely destroyed.

Upon reaching a height of approximately 1500 feet, and when in a nose high attitude and probably at a low airspeed, the aircraft entered a very steeply banked turn to the right. Almost immediately, the aircraft flick rolled several times to the right, then adopted a steep nose down attitude together with a rapidly descending, tight, spiral flight path which it maintained until it struck the ground. There was an intense fire which virtually consumed the wreckage. The examination of the wreckage was limited by the destruction but it was established that the engine was delivering considerable power at impact. The possibility that the pilot became incapacitated in flight was considered but rejected on the basis of the medical and operational evidence.

Having completed the sixth and final sortie for the day, the aircraft was observed to be approaching to land into the west and the approach path was rather higher than normal. After descending to a low altitude, overshoot action was initiated and the aircraft was next seen in a steep climbing turn to the right. The left wing dropped and the aircraft began a descending turn to the left, following which it was seen rotating to the right and descending rapidly. The aircraft struck the ground right wing first, cartwheeled through 90 degrees and came to rest 50 feet beyond the first point of impact. The wreckage was located some 720 feet beyond the western end of the strip. There was no fire.

The pilot had made only one previous take-off from the Huskisson camp helipad. This was during an area familiarisation flight which he had conducted earlier in the day. Prior to the familiarisation flight he had not flown a Bell 47 series aircraft for several months. The aircraft load on take-off consisted of two passengers and 35 pounds of baggage and freight. The temperature was about 18 degrees centigrade and a light north-easterly breeze gave a tailwind component of 3 to 5 knots in the take-off direction. The flight path after take-off was dictated by the terrain and lay across a heavilytimbered gully towards a saddle slightly higher than the pad. During the lift-off and initial hover the engine operation appeared normal. Because of the tailwind an increase in power became necessary during transition to forward flight. After travelling about 100 yards, during which time he applied full power, the pilot decided that the aircraft would be unable to clear the trees ahead. He turned back towards the take-off point and, when it became apparent that the rotor speed was decaying, continued the turn and allowed the aircraft to settle towards a partly-cleared area at the bottom of the gully. At a height of about 40 feet, the main rotor struck the surrounding trees. The aircraft fell heavily to the ground and burst into flames on impact.