Collision with terrain

The pilot had been spraying a plantation of fully developed banana trees which had vertical irrigation sprinklers protruding about 1 m above the canopy. The next area to be treated was in a hollow and consisted of half-grown trees with the sprinkler heads protruding about 2.5 m. The pilot reported that as he attempted to arrest the rate of descent after flying down into the hollow, the left wing struck one of the sprinkler heads. The aircraft immediately rolled left and struck a number of other sprinklers. The pilot was unable to regain control, and the aircraft struck the ground. The engine was torn from the airframe and both wings separated during the impact sequence. The cockpit area remained largely intact. There was no fire.

The aircraft was engaged in dropping parachutists. Prior to commencing the flight the pilot reported that he inspected the airstrip and calculated, from the performance charts for the aircraft, that adequate take-off distance was available. After lift off the aircraft did not climb as the pilot expected. He then turned the aircraft left to avoid trees at the end of the strip. In doing so the left wing struck a dead tree that the pilot had not seen.

A 10cm wide hole was torn in the undersurface of the wing from the leading edge to the aileron. As the aircraft continued to perform adequately the pilot decided to divert to the more suitable airfield at Coolangatta, 30 km to the north. The subsequent landing was without incident. The wind velocity was south-south-easterly at 10-15 knots and the take-off was conducted into wind. 

here is high ground to the north-west of the strip and under certain conditions downdraughts are present in the area of the strip. However, on this occasion the prevailing wind was not conducive to their formation. The reason for the lack of climb performance was not determined.

The student was making a practice glide approach to land, with the throttle in the closed position. Sink developed late on the approach with the airspeed reducing, and full power was applied. The aircraft touched down about two metres short of the sealed surface in a soft area. As the aircraft rolled forward the wheels contacted a 'step' at the start of the sealed area. The contact with the 'step' collapsed the main gear legs and the aircraft slid to a stop.

Significant Factors

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

1. The pilot under supervision misjudged the approach.

2. The instructor was late in assessing the situation and did not ensure power was applied in time to correct the sink rate and descent path.

The pilot reported that during cruise he experienced a loss of engine power associated with rough engine operation. He carried out a precautionary search and landed in a paddock. After landing, the engine was test run and could not be faulted. The pilot, having assessed that the available take-off length and surface conditions were adequate, elected to fly the aircraft from the paddock. The aircraft became airborne later than expected and struck a fence. A landing was made in the paddock immediately past the fence.

The aircraft was being ferried from Bankstown to Perth, a journey expected to extend over several days. During the first sector, the pilots became aware of non VMC weather at Wagga and decided to divert to Cootamundra. It was reported that at about the time this decision was taken, they noticed the left fuel tank was not feeding and that fuel was being drawn from the right tank only. Assuming a fuel system malfunction, and a reduced endurance of about 15 minutes, the pilot-in-command decided to carry out a precautionary landing.

A section of gravel road was chosen for a landing site, as nearby paddocks were unsuitable. Although the touchdown was normal, the aircraft began to veer to the right on the heavily cambered road surface. When the pilot was unable to regain directional control, full power was applied for a go round. The aircraft became airborne, still diverging to the right, and collided with a boundary fence before nosing over into an adjacent paddock. The Skyfox CA 22 aircraft has two fuel tanks, one in each wing, which feed into a common collector tank via a two position, on/off fuel selector. Each tank is vented via a port in each fuel cap.

Asymmetric fuel flow from the tanks is known to occur occasionally and one tank is exhausted first, upon which the remaining tank feeds normally. The manufacturer is expected to soon issue an amendment to the Flight manual by which pilots will be warned by a cautionary note of this phenomenon.

The aircraft and instructors from an aero club were based at Eulan Downs to train a group of five students to the general flying progress test (GFPT) standard. The instructor and student had planned to carry out an upper air sequence prior to returning to Fairfield to commence circuit training. After the completion of the upper air flying the instructor decided to demonstrate a practice forced landing. The forced landing was commenced at 2500 feet above mean sea level (the elevation of the airstrip is 600 feet amsl).

During the descent the instructor found it necessary to adjust his circuit, to ensure a landing on the airstrip, such that a base turn was commenced approximately abeam the threshold and the aircraft aligned on final at about 20 feet above the ground. The instructor reported that the indicated airspeed was 60 knots and the flaps were still selected up when the aircraft was aligned on final. The aircraft stalled at this point and landed heavily on the airstrip. All three legs of the landing gear were torn off and the aircraft slid for about 20 metres before coming to rest.

On the second flight for the day the pilot took off with an identical load as on the first flight, but the aircraft would not climb after liftoff. The aircraft was operating with a tailwind, and it was suggested that a gust may have reduced aircraft performance. The pilot recognised the lack of performance immediately and commenced dumping the load, but the performance did not increase sufficiently to avoid contact with two fences and some scrub. Although the aircraft was damaged, the pilot was able to fly a circuit and land on the strip.

The pilot was conducting his first take off on the strip. The fully loaded aircraft did not accelerate to flying speed by the end of the strip. The pilot had looked out of the cockpit to identify another company aircraft operating in the same area whilst his aircraft was accelerating down the strip. When he eventually found the other aircraft and returned his attention to the aircraft performance, the pilot determined that the aircraft would not clear the obstacles at the end of the paddock, so he commenced a load dump. He attempted to fly the aircraft over the obstacles, but it hit the tops of several low trees and a fence before colliding with a more substantial tree which swung the aircraft around and caused the right undercarriage leg to collapse.

The pilot felt that long grass and soft earth combined with the maximum all up weight of the aircraft to reduce its take off performance. He had thought, from his initial inspection, that there was sufficient length available for take off from the point where he commenced his take off roll.

The pilot advised that, while carrying out a practice forced landing at the conclusion of a local scenic flight, he allowed the aircraft to become too slow and too low. As a consequence the aircraft touched down and nosed over approximately 40 metres short of the runway threshold. The aircraft's left wing and propeller were substantially damaged as a result of the ground contact.

The pilot confirmed that there was no mechanical fault with the aircraft's engine or flight controls that would have contributed to the accident.