Runway excursion

Circumstances:

The aircraft was conducting spraying operations. The pilot reported that the aircraft failed to remain airborne after encountering a severe "willy willy" at the liftoff stage of the take-off. He initially dumped part of the load, then dumped the remainder as the aircraft was making contact with the ground. An area of long grass and thistles then prevented the aircraft from becoming airborne. As a result, one main landing gear was torn off and the other damaged.

The takeoff was carried out downhill, at maximum gross weight, on a 570 metre agricultural strip with a load of superphosphate. When the aircraft had not become airborne with 60 metres of strip remaining, the pilot commenced dumping the load. However, the aircraft overran the strip before becoming airborne and flew very low over the surface of a farm dam. The landing gear impacted the earthen dam wall and the left maingear assembly detached from the airframe. The aircraft continued descending down a gully, through scrub, before settling into rocks. It then slewed around and came to rest upright. As the pilot vacated the wreckage, a fire erupted in the engine bay. The aircraft was subsequently destroyed by fire. An inspection of the wreckage did not reveal any fault that may have contributed to the occurrence. From a witness's description of the combined noise of the engine and propeller during the takeoff roll, it is probable that the pilot attempted the take off without the propeller in the full fine pitch position. Examination of the wreckage found the pitch control setting in the mid-range position.

Circumstances:

The pilot with considerable rotary wing but limited fixed wing experience, was conducting a flight to an airstrip which he had previously inspected by motor vehicle. The airstrip is aligned 080 degrees magnetic, approximately 870 metres long, and is located on the northern side of a tree enclosed paddock. On arrival, and without further assessment of the airstrip characteristics, the pilot joined the circuit for a landing to the east into a slight headwind. During final approach he lined-up to the right of the airstrip until alerted by the front seat passenger. The pilot then realigned the aircraft with the actual strip while continuing the approach. Despite being high he did not consider going around. Crossing the threshold the pilot estimated his height as 50 feet above ground level with an airspeed of 90 knots. The aircraft bounced on initial landing and did not settle until almost 400 metres beyond the threshold. During the landing roll and with only 250 metres remaining, the pilot considered but then disregarded going around. He applied heavy braking causing the main wheels to lock-up. The aircraft skidded and overran the strip before entering a three metre wide track of soft soil, with a slight rise of firm ground on the far side, which partially dislodged the landing gear. It then continued for a further nine metres before coming to rest ten metres to the right of the airstrip centreline, on a heading of 115 degrees magnetic. The aircraft Flight Manual landing weight chart indicates that the airstrip length was adequate.

Significant Factors:

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

1. The pilot failed to perform an adequate pre-landing inspection of the airstrip.

2. The pilot carried out an inaccurate approach to land.

3. The pilot failed to carry out a go around.

4. Insufficient stopping distance remained following touchdown.

In order to avoid thunderstorms in the immediate vicinity, the pilot requested take-off from a runway direction giving a slight downwind component. Light rain was falling at the time, but increased in intensity shortly after the aircraft commenced to roll. The initial stage of the take-off run was normal, but the aircraft then failed to accelerate. The take-off was abandoned at about 65 knots Indicated Air Speed, however braking effectiveness was reduced because of the wet runway conditions. A ground loop was attempted, the nosegear subsequently became detached and the aircraft slid sideways into the aerodrome boundary fence. No fault or defect was subsequently found with the aircraft engines, propellers or braking system which might have contributed to the development of the accident. A detailed engineering study revealed that under the existing conditions the wind velocity, rainfall rate and runway slope combined to prevent normal drainage off the runway. As a result, water tended to pool on the runway to a greater depth than anticipated. Quantitative estimates indicated that under these conditions, the rate of acceleration of an aircraft could be reduced by up to 50 percent. When the pilot abandoned the take-off attempt and applied the brakes, the depth of water present was such that the aircraft commenced to aquaplane.

On arrival in the circuit area, the pilot assessed the wind to be from the south-west at 10 knots. He elected to land downwind, as the strip sloped slightly uphill to the north-east. Touchdown occurred about halfway along the strip, and the pilot was unable to bring the aircraft to a stop in the distance remaining. The aircraft collided with a fence and came to rest 60 metres beyond the end of the strip. The strip was undulating, with the slope in the landing direction varying from 2 up to 1.5 down. The average upslope was in the order of 1 , and the pilot evidently misjudged the effect this slope would have on a landing in downwind conditions. The aircraft crossed the threshold slightly higher than the pilot desired, and it floated for a considerable distance under the influence of the tailwind. After touchdown, the pilot was reluctant to carry out a go-around because of the slope.

Following a local flight the pilot positioned the glider to join the circuit for a landing on the grass strip 24. The wind velocity was reported as 240 to 280 degrees at 10-15 knots with occasional gusts to 18 knots. After lining up on final approach, the pilot inadvertently raised the landing gear instead of extending the air brakes. As the approach continued it became apparent the glider would overshoot the runway. The glider was banked to the right to remain within the confines of the aerodrome. The right wing tip struck the ground and the glider ground looped.

Circumstances:

The pilot reported that he had planned to fly a triangular course from Cunderdin to Cunderdin. After spending over 3.5 hours, in difficult weather conditions, to get to his first turning point the pilot elected to return direct to Cunderdin. When he arrived back at Cunderdin, the pilot spent 45 minutes in the local area before returning to land. The pilot decided to land well into the shorter of the two runways, to reduce the effort required to move the glider into a hangar however, he had forgotten that the wheel brake was not working. The aircraft touched down over halfway down the 1200 metre runway. With 300 metres to run, the pilot became concerned at the slow rate of deceleration, and it was at this point he remembered the unserviceable wheel brake. Although he believed it would not be necessary the pilot decided he would intentionally ground loop the aircraft when there was 50 metres to run if it was not slowing adequately. The aircraft's speed was still close to 20 knots, when there was 50 metres to run, and the pilot was forced to attempt a ground loop. The ground loop attempt only succeeded in altering the direction of travel and the aircraft stopped after crossing a ditch and hitting a fence. The pilot advised that he did not think to use the airbrake to slow the aircraft once it was on the runway.

Circumstances:

The pilot intended to land on a small knoll in the centre of a large, cleared area in heavily timbered country. During the flare to land over a large depression, the pilot noticed a lack of power accompanied by the Low Rotor RPM Warning Horn. He lowered the collective control and wound the throttle to maximum in an attempt to regain rotor RPM. In doing so, he oversped the engine and rotor, and subsequently overshot the landing site. He was convinced that he had a genuine power problem and elected to land in a gully beyond the knoll. The tail rotor struck ground in the steeply sloping gully, resulting in the tail boom being cut off by the main rotor. The cabin came to rest on a heap of storm debris. During later investigation, the engine was ground run successfully. A small fuel leak existed at the carburettor, but this did not affect the fuel supply to the engine. The pilot had not received any training in ridge line operations. He had made his approach using visual cues only, which can result in a steep final approach accompanied by a high rate of closure. In addition, the pilot was unaware of the local wind velocity, and the aircraft was probably subject to local airflow effects. While attempting to compensate for these, it is probable that the pilot over-pitched the main rotor blades leading to a temporary reduction in main rotor RPM. He subsequently misread the symptoms as an engine malfunction.

Significant Factors:

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

1. The pilot was inexperienced in ridge line operations.

2. The pilot did not maintain adequate rotor RPM during the latter stages of the approach.

3. The pilot considered that the engine had failed

 4. The aircraft was force landed on unsuitable terrain.

Circumstances:

The pilot arrived in the area of his destination about sunset but was unable to locate the station airstrip. After a short search he found another strip with some buildings nearby and decided to land to ascertain his location. An aerial inspection of the strip was completed. However, the pilot reports that when the aircraft was on final approach, he noticed that what he had assumed was low scrub near the threshold was in fact 10 metres high trees. He adjusted the approach and touched down further down the strip than had been planned. The strip surface was loose, and maximum braking could not be applied. The aircraft overran the strip and collided with rocks and a dirt bank which resulted in the left main and nose landing gear legs collapsing. The strip was approximately 800 metres in length.

The aircraft touched down about 300 metres after the threshold of the 1200 metre long strip, which sloped uphill. When the pilot realised that the aircraft would not stop before the end of the strip, heavy braking was applied. The aircraft overran the strip and the nose gear strut collapsed in the rough terrain. The pilot subsequently advised that had he initiated braking earlier the aircraft would have stopped in the remaining lenght. He had believed that there was more strip length available than was actually the case and it was considered probable that he had been deceived by the slope of the strip.