Loss of control

The gyroglider was being towed in alternate directions along a strip. There was a 10 knot wind component along the strip direction and the temperature was 34 degrees Celsius. During one downwind towing sequence the wind speed increased. The pilot signalled for a higher towing speed, but as the vehicle driver had been instructed to observe a limit of 80 kph, he did not increase speed further. The gyroglider subsequently landed heavily and overturned. The high density altitude conditions, coupled with the gusting tailwind and aircraft weight approaching the maximum permissible, required a towing airspeed higher than normal. Towing speed was limited by fixed ground speed limits.

A low level aerobatic display was being conducted over the lake. Towards the end of the display the pilot performed four snap rolls followed by a steep climb and stall turn. Although the display was to be conducted not below 500 feet agl the aircraft was recovered from the last snap roll at an estimated 150 feet agl. Despite this low recovery height the pilot persisted with the climb and stall turn manoeuvre. While attempting to recover from the subsequent dive he stalled the aircraft at too low a height to avoid impacting the water.

During the landing roll the aircraft suddenly veered to the left. The pilot took corrective action but the nose gear collapsed and the nose section of the aircraft struck the strip surface. Although the strip was in regular use it was not being inspected. It was constructed on a dry lake-bed and the combination of no rain and regular use caused a soft patch to develop about 430 metres from the threshold. When the aircraft entered this area the nosewheel progressively turned left until it reached the stop. The sideload now imposed was too great and caused the noseleg bearing to fail.

The aircraft was attempting a take off from Northam Airfield at the time of the accident. The student pilot was flying the aircraft and another student was acting as wingtip walker. The wingtip walker inadvertently held the left wing up against aileron control input from the pilot. When the wingtip walker released the wing, the aircraft rolled rapidly to the left. The wingtip, which was fitted with a combination metal tie-down point and skid, collided with the ground, the skid dug in and the aircraft ground looped. This accident was not the subject of an on-site investigation.

Because the external load could not be released electrically, the pilot landed on snow to allow an assistant to release the load manually. After the load was released, the assistant had moved to the pilot's window to discuss the next load when the rear of the left skid began to sink into the snow. The pilot attempted to correct the situation but the main rotor struck the ground and the aircraft rolled over. The helicopter was not fitted with any load spreading devices for operations in snow. Although the pilot had tested the load bearing capacity of the snow, the technique did not provide sufficient indication that the snow could not support the aircraft. An intermittent electrical malfunction is believed to have caused the cargo hook failure.

Circumstances:

The solo student pilot was conducting left-hand circuits on runway 27 in a westerly wind of about 15 knots. When he transmitted his "base" call on VHF frequency 119.1, he neither heard nor saw another aircraft in the circuit. During the landing roll he realised he was on a collision course with a Piper PA28 which had landed on runway 36. He applied brakes and veered left while attempting to avoid a collision. At the runway intersection both aircraft missed each other by about one metre. After the near-miss the student applied full power for a go-around but his aircraft veered further left. As he attempted to steer back on to runway 27, the left side of the horizontal stabiliser struck the airfield boundary fence. The pilot of the Piper PA28 was conducting an Instrument Flight Rules flight via Avalon. The PA28 was equipped with only one VHF radio. The pilot said that while still in the Avalon control zone he called Geelong on 119.1 to advise his ETA. He said he was told the wind was westerly but could not recall being advised of traffic. He then returned to Avalon tower frequency. Geelong Airport personnel said the pilot was advised that the duty runway was runway 27 and that there was a Cessna 152 operating in the circuit. As 119.1 is not recorded it was not possible to check exactly what was said. Passing Avalon control zone boundary (approximately nine kilometres north of Geelong) the pilot selected the Melbourne area frequency 124.9 and remained on 124.9 for the arrival at Geelong. Flight Service advised of following traffic also destined for Geelong. The PA28 joined on downwind for a right circuit for runway 36. On the downwind leg, the pilot saw a Cessna to the left and about 400 feet below. He thought this aircraft was in transit whereas it was actually on the base leg for runway 27. He had no further sighting of the Cessna until established on the landing roll, at which time the PA28 passenger gave warning of a possible collision.

Recommendations:

It is recommended that the Civil Aviation Authority clarifies the practice of using 119.1, particularly at Authorised Landing Areas, and produces relevant documentation for pilots.

Circumstances:

The pilot had owned the gyrocopter for some time but had flown it infrequently due to engine tuning problems. On previous flights, the pilot had flown from a larger strip near Innisfail. Since then, he had enhanced the engine instrument cluster to better monitor the performance of the turbocharged engine. The pilot's intention was to test the new instrument installation at the smaller Deeral strip before proceeding to the larger strip for further flying practice. He had planned to make six runs along the 500 metre long strip without becoming airborne, with a 15-knot crosswind. On the fifth run, the witness noticed that full power was applied for much longer than on the previous runs. The aircraft accelerated to flying speed and became airborne. At a height of about six feet above the strip, the pilot appeared to experience some difficulty with the crosswind. The gyrocopter banked and yawed to the right, it then dived into the ground, and cartwheeled forward before coming to rest in a drain.

Significant Factors:

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

1. The pilot was inexperienced.

2. The wind conditions were unsuitable for the operation attempted by the pilot.

3. The pilot lost control of the aircraft due to crosswind and turbulence.

Recommendations:

In this accident the pilot may not have been injured as seriously if he had been using a harness which prevented him from sliding forward underneath and out of the harness. A five or six point harness with a crotch strap would have held the pilot in his seat where the surrounding structure would have offered more protection.

1. It is recommended that the Sport Rotorcraft Association of Australia should disseminate information to its members on the advantages of using seat belts with additional mounting points.

On return to Moorabbin from the training area the pilot attempted two crosswind touch-and-go landings on Runway 31 right using 20 degrees of flap and normal approach speeds. The first was successful. On the second approach the aircraft touched down well into the runway and he had difficulty keeping the aircraft straight during the landing roll. After a ground roll of about 250 metres the pilot decided to make the landing a full stop because he thought that there was insufficient runway remaining for a touch-and-go. In reality there was still about 600 metres of runway available for a go-around. As the aircraft slowed down the pilot had increasing difficulty keeping the aircraft straight. With the wind of 250 degrees gusting from 12 to 19 knots, the aircraft veered left. He decided to try to bring the aircraft to a controlled stop on the grass with the intention of taxiing back on to the runway. A short distance after leaving the sealed runway the nosewheel sank in soft damp ground and the aircraft slowly tipped up on to its right wing tip before settling back on to its wheels. During his previous training the pilot had completed one lesson in crosswind landings with an instructor. However the gusty crosswind conditions on the day of the accident were more severe than he had encountered before and he was unaware that the grass surface was soft. This accident was not the subject of a formal on scene investigation.

Circumstances:

The aircraft was being used for a pleasure flight for the owner and some friends. The Captain calculated the landing distances required for both runway 28 and 10, based on weather reports obtained at briefing, which indicated a strong northerly wind component. An updated report received some 30 minutes before descent confirmed the wind as 290 degrees at 7 knots. Approaching the island and becoming visual, the crew noted the windsock near the western end of the runway to be indicating a slight headwind component in the 10 direction and decided on a straight in approach to runway 10, to avoid an approaching squall/shower. The aircraft touched down firmly a short distance beyond the threshold. Speed brakes were immediately extended and wheel braking applied. About four seconds later the Captain called for the drag chute to be deployed. Although the co-pilot correctly activated the handle, it became obvious that the chute had not deployed as no increase in retardation occurred. When the Captain realised that the aircraft could not be stopped on the runway remaining, he attempted to turn the aircraft towards a clear grass area to the right. However, the aircraft was aquaplaning on the wet surface and did not respond to steering inputs for some distance. The aircraft left the bitumen tracking to the right. It collided with a gable marker, passed through a fence, continued down an embankment, across a road, through a second fence and came to rest approximately 90 metres from the runway end and 70 metres to the right of the extended centreline. The left main and nose gear legs were torn off. Witnesses to the accident said that when the aircraft landed, the runway was very wet, and the wind was westerly at 5 to 10 knots. It was determined that the Captain had made some miscalculations in his pre-flight assessments. He had noted the landing distance available as being the same for both runways, whereas runway 28 has a reduced length due to terrain clearance requirements on the approach. Under the conditions both forecast and prevailing, and using the criteria applicable at the time for an aircraft fitted with an alternate means of retardation, i.e. drag chute, the landing distances required for both runways were greater than the landing distances available. The Captain had also evidently applied incorrect techniques during the landing. He had not attempted to deploy the drag chute immediately the nosewheel was on the ground and had not applied unmodulated pressure to the anti-skid braking system. These measures are required by the manufacturer to obtain maximum performance. It was found that the drag chute canister lid had been sealed with tank sealant and painted over. The latch assembly had operated but the drogue chute spring was insufficiently strong to break the seal. When the sealant was prised away from around the lid, the system operated normally. This error had not been found during a check of the aircraft immediately following repainting. The lid had the appearance of an oblong radio antenna and was not marked in any distinguishing manner. The problem should also have been noticed during a subsequent inspection of the drag chute for moisture. The inspection is required every 90 days if the drag chute has not been deployed and requires the removal of the lid and drogue chute in order to feel the main chute for moisture. The condition of the sealant would indicate that this had not been carried out.

Significant Factors:

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

1. Inadequate pre-flight planning and preparation by the flight crew. The runway distance required was in excess of the distance available on either runway.

2. Adverse runway and weather conditions - wet surface and downwind component.

3. Improper sealing of drag chute canister.

4. Inadequate maintenance of the drag chute system. 5. Improper operation of wheel brakes.

Recommendations:

1. It is recommended that where a drag chute is fitted, the Civil Aviation Authority considers requiring some type of appropriate marking be applied to the canister lid to clearly identify its purpose.

The student pilot was attempting a full stop landing while under instruction. The wind was light and variable with occasional gusts producing 6 knots of crosswind from the left on runway 23. The approach, flare and touchdown were reported to be uneventful. About two seconds after touchdown the aircraft was hit by a wind gust and swung suddenly to the left. The student pilot immediately applied full right aileron which pitched the aircraft on to the right wingtip. It then pivotted heavily onto the nose gear which collapsed. The aircraft skidded to a halt on the sealed surface.