The pilot reported that he had an electrical failure whilst enroute to Albany. He elected to continue the flight on battery power. The pilot reported the night landing at Albany was normal but that the nosewheel had collapsed during the landing role and the aircraft had slid to a stop on its nose.

An engineer who inspected the aircraft reported that the aircraft had suffered a heavy landing damaging both the nosewheel retraction/extension rod and the rear, lower fuselage tie down point. The nosewheel had collapsed because the retraction/extension rod had failed in overload.

It is possible the pilot, deprived of normal cockpit illumination by low battery power, misjudged the approach and allowed the aircraft to land heavily.

After engine start, with the engines idling, and his feet resting on the brakes, the pilot turned his attention to the inside of the cabin to complete some checks. A short time later the pilot realised that the aircraft was moving. He reduced the power and applied the brakes but before the aircraft was brought to a stop, the left propeller hit a tyre that was being used as a marker at the edge of the parking bay.

The pilot shut the engines down and inspected the left propeller. He could find only very slight damage so decided to run the engine. He ran the engine through a range from idle to 2300 RPM and noted no vibration. He then decided the aircraft was fit to fly back to Moorabbin.

The return flight to Moorabbin was without incident. After landing the pilot experienced vibration from the left engine. Subsequent engineering inspection revealed the following damage:

• One blade bent one degree at the 32 inch station. Blade circlip out of its groove and the groove damaged with rolled edges.
• One blade bent one degree at the 30 inch station and twisted two degrees.
• One blade bent two degrees at the 30 inch station. Blade circlip out of its groove and the groove damaged with rolled edges.
• All circlips, blade preload shims, shim plates and shim carriers damaged beyond repair. There was no damage to the hubs or pitch change mechanisms.
• In addition, some counterbalance weight retaining screws had broken, allowing liberation of the weights.

FACTUAL INFORMATION

During the descent, the second officer was the pilot flying from the right seat. The pilot in command was in the left seat, and he was monitoring and performing support duties including communication with air traffic control (ATC). The co-pilot was monitoring the approach and assisting with support duties.

The aircraft had been cleared by the Cairns Sector Controller for descent to 7,000 ft tracking inbound on the Cairns VOR 153 radial. After communications were transferred to Cairns Approach, the aircraft was cleared to continue descent to 6,500 ft. The controller told the crew to expect a straight-in approach to runway 33, and to report when in visual meteorological conditions (VMC).

At 32 DME the pilot in command requested further descent "as per the DME steps." The controller then issued a clearance "from two zero DME descend to three thousand not below the DME steps." The clearance was correctly acknowledged. (The clearance required the aircraft to remain at 6,500 ft, the last cleared altitude, until reaching 20 DME.)

The pilot in command said that after receiving a clearance to descend to 3,000 ft "not below the DME steps", he had set 5,400 ft in the altitude-select window and permitted the second officer to commence the descent in VMC. The pilot in command stated that the aircraft was maintained in VMC, but because he could not see the runway, he instructed the second officer to return the aircraft to 6,400 ft. ATC also issued a climb requirement at the same time. The pilot in command stated that at no time was the aircraft in instrument meteorological conditions.

The co-pilot had been absent from the flight deck when the clearance to descend to 3,000 ft was issued. When he returned he noted that the altitude alert window had been set to 5,400 ft, and he queried the flight engineer. The flight engineer replied that they had been cleared for a visual approach. The co-pilot was satisfied with the situation as the aircraft was in VMC. The flight engineer later said that he had some difficulty hearing the flight deck conversation and monitoring the radio transmissions at the same time.

At the time of the occurrence, the DME arrival procedure specified a lowest safe altitude of 6,400 ft from 32 DME to 20 DME and 5,500 ft from 20 DME to 16 DME. In this instance, the crew had been instructed to remain at 6,500 ft until 20 DME and then descend in accordance with the remainder of the DME Arrival procedure.

The radar data showed that the aircraft left 6,500 ft on descent at 33 NM, passed through the lowest safe altitude of 6,400 ft at 32 NM, and levelled at 5,600 ft at 29 NM. This altitude was maintained to 25 NM when the aircraft climbed to 6,500 ft.

When the aircraft was at 25 NM, the approach controller noticed that the transponder altitude readout indicated 5,700 ft. This placed the aircraft below the minimum safe altitude for the step of 6,400 ft and the controller instructed the crew to climb to 6,500 ft, which was carried out. When the crew subsequently reported "visual" approximately 30 seconds later, the aircraft was cleared to descend from 6,500 ft to 2,500 ft. The co-pilot resumed his position in the right seat when the aircraft was descending through 4,000 ft.

ANALYSIS

Crew resource management (CRM)

The first officer was absent from the flight deck during a period when crucial descent clearance information was received. The flight engineer was not adequately monitoring the situation as the exchanges between the pilot in command and the second officer were not clearly audible.

DME arrival

There have been reported occurrences where an error was made by the crew in reading and applying the DME arrival procedure such that a descent was initiated to the sector level one step too early, thereby descending below the lowest safe altitude. In this occurrence the aircraft followed a descent profile which was consistent with this error; specifically, the aircraft was descended towards 5,500 ft, which was the lowest level for the next sector.

SIGNIFICANT FACTORS

1. The crew misinterpreted the clearance and initiated a descent below their cleared level.

2. The altitude alert window was incorrectly set to 5,400 ft.

3. The co-pilot was absent from the cockpit when the clearance to descend to 3,000 ft was issued and was told incorrectly that the aircraft was cleared for a visual approach.

4. The aircraft descended below the lowest safe altitude before the crew reported visual.

SAFETY ACTION

The Bureau of Air Safety Investigation is currently investigating a perceived safety deficiency that has been identified as a result of this and a number of similar occurrences. The deficiency relates to the presentation of distance and descent altitudes on DME/GPS arrival charts that may be misinterpreted by flight crew.

Any recommendation issued as a result of this investigation will be published in the Bureau's Quarterly Safety Deficiency Report.

The aircraft was engaged in a powerline inspection. The crew had identified a downed powerline. During an approach to land, to carry out a closer inspection, the helicopter collided with a second powerline that was still in place. It crashed in a near vertical attitude.

Wreckage inspection indicated that one main rotor blade had made solid contact with the powerline.

The pilot indicated, before his injuries took full affect, that he had forgotten about the second line. He has been unable to provide any further information.

The pilot reported that the engine lost power shortly after take-off and he landed the aircraft in a ploughed field. During the latter stages of the approach, he saw smoke coming from the engine compartment. The aircraft subsequently burnt out.

The pilot was conducting a local flight in weather conditions which were fine, but with a gusty 20-25 kts south-easterly wind blowing.

On return a normal approach for landing was made at 85 kts, with the touchdown at 80 kts. About 250 metres into the landing roll a wind gust, combined with the aircraft canard design and undulation in the airstrip surface, caused the aircraft nose to pitch up through 45 degrees, and become airborne again.

Before the pilot could take recovery action the aircraft stalled and impacted the airstrip in a steep nose down attitude. It then bounced and skipped across the ground on its nose for about 28 metres before tipping over onto its back.

The aircraft had touched down, following the third circuit, when it began to yaw right into the crosswind. The pilot applied full left rudder and some power, but the aircraft did not respond. The aircraft continued to yaw right, and the left-wing tip touched the ground. The pilot closed the throttle, but the aircraft continued off the runway and on to the grass flight strip. The left wing struck a runway distance-to-run marker before the aircraft came to a stop.

It was reported that there was a five knot crosswind from the right at the time of the landing.

Shortly after take-off an EICAS message 'flap Disagree' was indicated. The crew took appropriate action and the flight was continued.

During climb out at FL205 a loud bang was heard accompanied by fluctuating right engine instrument indications and a yaw effect. The right engine was shut down and the aircraft returned to land at Melbourne.

For the flap problem the rectification consisted of replacement of the trailing edge flap bypass valve.

For the engine malfunction the engine was changed.

Significant Factors

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

1 Defective trailing edge bypass valve.

2 Right engine malfunction, reason undetermined.

The pilot was engaged in circuit training at the time of the accident. He reported that, during the circuit conducted prior to the accident, the controls felt stiff although they appeared to be working correctly.

Following touchdown, with the tail down and the pilot holding the stick back, the left wing started to dip. The pilot initiated a go-round and applied full power. The aircraft began to veer to the left and the pilot was unable to correct the turn with either rudder or ailerons. The aircraft crashed inverted, 60 metres to the left of the centre line, still with full power applied.

The crosswind at the time of the accident was approximately 8 knots from the left. The reason for the reported stiffness in the controls was not determined.

Enroute the pilot encountered unforecast fog and low cloud and decided to carry out a precautionary landing. Rain had fallen on the surrounding countryside, causing the pilot to have doubts over the surface condition of paddocks in the area. Hence, an unopened, new section of the Hume highway was selected. Low runs were made over the area to check the surface condition, which appeared suitable. A section about 1200 metres long was selected.

A normal landing was achieved and as the aircraft slowed down it unexpectedly entered a 30 centimetre deep track across the highway surface. The undetected track had been left in the surface to allow vehicles to cross the constructed area. As a result of entering this area the nose and right main gear legs collapsed.

Significant Factors

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

1. The pilot encountered weather conditions precluding further flight in visual conditions and therefore necessitating a precautionary landing.

2. The area selected for the precautionary landing contained a hazard (a 30 centimetre deep track) which the pilot did not see during a precautionary search from the air prior to landing.