Runway excursion

The pilot had earlier landed in the paddock which was adjacent to the homestead to seek assistance regarding a broken down vehicle being used in the spraying task. Prior to commencing the takeoff run the pilot did not inspect the proposed takeoff path. Initially the aircraft takeoff run acceleration was more sluggish than normal, due to the traversing of patches of soft wet ground. Acceleration improved. However, the aircraft was approaching some trees so the pilot turned it to provide a greater ground roll distance. The aircraft became airborne for a short time, but then touched down in long wet grass which degraded its acceleration. It then hit a fence and nosed over.

The pilot was conducting a bank-run flight. It was raining heavily when the aircraft arrived at Canberra, and the pilot took shelter while freight agents attended to the load. When this operation was completed, the pilot ran back to the aircraft, quickly boarded and prepared for DEPARTURE. Although Runway 35 was the runway in use, he was given a taxy clearance for DEPARTURE from Runway 12, as the cloud base and visibility were better in that direction, and the wind was light and variable. It was still raining as the takeoff roll was commenced, with water accumulation on the runway retarding the acceleration of the aircraft. At the start of the roll the pilot heard a tapping noise coming from the left hand side of the aircraft, which he thought may have been a strap from his seat belt hanging out of the door, but a quick check confirmed that his seat belt was correctly fastened. As speed increased the noise subsided, and as both engines appeared to be operating normally, the takeoff was continued. However, at the point of rotation the noise returned, louder than previously, and the pilot suspected that there was a fault in the left engine. As it was apparent that the aircraft would enter cloud shortly after becoming airborne, the pilot made a decision to abandon the takeoff. The aircraft touched down approximately 550 metres from the end of the runway, and during the application of heavy braking the aircraft aquaplaned along the wet runway. After crossing the threshold it continued through the boundary fence, across a road, then came to rest in an adjoining paddock. A length of the cargo restraint webbing was found hanging out of the cabin door, allowing it to flap against the side of the fuselage. Canberra Runway 12/30 has a known drainage problem during rain periods, and other aircraft have also experienced aquaplaning following abandoned takeoffs.

The pilot held a Student Licence as issued by the AUF. During a landing approach the aircraft overshot the intended touchdown point. It subsequently ran off the end of the strip and collided with a tree. It was reported that the student was not being supervised by an instructor at the time of the accident. The reason he apparently misjudged the approach was not determined.

During the course of the day's activities, the pilot had landed at the strip on 24 occasions. The surface was wet and landings had been made with a quartering tailwind. On each occasion the pilot had stopped the aircraft about 100 metres short of a cattle yard at the end of the strip. The pilot was making his first approach after changing operations to another paddock. The aircraft touched down about 100 metres beyond the previous touchdown area. However, the pilot continued with the landing and despite heavy braking he was unable to prevent the aircraft colliding with the fence of the cattle yard. It was reported that while the aircraft was on approach the wind strength increased to about 15 knots.

After a lesson of simulated instrument flying and some stall revision, the student was carrying out a practice forced landing at Wallacia Airstrip. He did not hear the instruction to go around and the aircraft touched down. At this point, the instrument hood, which he was still wearing, fell down over his eyes. As he moved the hood, he displaced his headphones. He heard the instructor say "full power", so he retracted flap and then applied full power. The instructor, realising the aircraft was too far along the strip to successfully clear the trees on the climb out, took over, closed the throttle and applied full braking. The grass was wet and the aircraft overran the strip and struck a fence. The nosegear collapsed.

The pilot had intended to carry out a scenic flight which would include aerial photography of a property at Merrijig. An enroute landing was not planned, but the pilot subsequently advised that one of his passengers became unwell and a decision was made to land at a grass strip near the property. Take-off from this strip was commenced about 90 minutes later, and the acceleration was reported to be slower than expected. The aircraft was pulled into the air near the end of the strip, but it then descended, ran through two fences and collided with some disused farm machinery. It came to rest in a nearby river bed. Prior to the attempted take-off, the pilot had made calculations from the performance charts in the aircraft. However, the strip was 100 metres shorter than estimated, and the pilot also incorrectly assessed the take-off weight of the aircraft. Based on the corrected figures, the charts indicated that about 1030 metres would have been required for take-off. The strip being used was only 550 metres in length and, although it had a downslope, it was covered in grass some 20 centimetres high. The long grass had slowed the rate of acceleration of the aircraft and flying speed could not be obtained under the conditions.

When the aircraft had reached a height of about 300 feet agl the winch motor lost power. The pilot released the launch cable and attempted to land straight ahead but the aircraft overshot the end of the landing area and collided with trees. It was considered that at the time of the winch failure, sufficient strip length remained to permit the aircraft to land safely. However, the pilot had not deployed the dive brakes early enough to prevent the overshoot. The reason for the loss of power from the winch motor was not established, and subsequent operations were reported to be normal. This accident was not the subject of an on-scene investigation.

Circumstances:

The pilot had landed at the 800 metre long strip previously. The strip had an uphill slope to the west. When he arrived in the circuit area the pilot said the windsock indicated a 10 - 12 knot easterly and he noted another aircraft landing into the west. Taking into consideration the landing direction of the other aircraft and the uphill slope, the pilot decided to land into the west. The aircraft touched down about halfway along the strip. The pilot considered that the aircraft would not stop in the remaining distance, so he applied full power to go around. The aircraft just cleared a fence at the end of the strip but then descended and struck a second fence about 190 metres further on. It then veered left and eventually came to a stop some 400 metres beyond the end of the strip.

The aircraft was being operated from a strip which had been cleared in a hay paddock. The pilot was aware that the strip was of marginal length and had therefore reduced the load to be carried. On take-off, the aircraft accelerated normally to about 40 knots but the performance then appeared to stagnate. The pilot attempted to dump the load, but only partial dumping was achieved before the right main gear struck a fence post as the aircraft became airborne. The impact displaced the gear, however the aircraft remained under control and the pilot diverted the aircraft to a more suitable aerodrome. The right main gear became completely dislodged during the landing. A subsequent inspection of the strip revealed that it had a soft sandy surface, covered with short and thick grass. Heavy rain had fallen in the area during the night and early morning, and the grass was very wet at the time of the take-off. When calculating the load he could safely carry from the strip, the pilot had not appreciated the degree to which the surface conditions would affect the take-off performance.

Circumstances:

The pilot intended to conduct spreading operations on nearby sugar cane fields. During the latter part of the first take-off of the morning, the aircraft failed to lift off as anticipated and entered a sugar cane field at the end of the airstrip. The pilot discontinued the take-off, but the aircraft was substantially damaged when it ran into a ditch, in which lay several disused telegraph poles. The pilot reported the aircraft encountered an isolated tailwind gust during the take-off. He said he attempted to dump the load but was unsuccessful due to the damp condition of the fertiliser.

Significant Factors:

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

1. The aircraft encountered an isolated tailwind gust during the critical stage of the take-off.
2. The load did not dump due to its damp condition.