The instructor was embarking on an introductory flight with a prospective student. The wind on the duty runway was outside the aircraft limits so the instructor elected to use a different runway where the crosswind was within the aircraft limits. As the tail was raised off the ground the student applied incorrect aileron input for the crosswind and the right wing lifted, causing the aircraft to ground loop off the runway. Before the instructor could regain control, the aircraft hit trees at the edge of the airport boundary.

Before spraying a field cultivated with tomatoes, the pilot made a ground inspection to note the position of powerlines and other obstacles. Not long before departing on the spraying job, he was asked to spray an additional block in the same vicinity.

He completed spraying the first paddock without incident and moved onto the next block where he conducted an aerial inspection for obstacles. He noted that the same powerline crossed this block as well as the previous cultivation. He did not notice that one of the three wires was hanging lower than the other two. During his last spray run, which co-incided with the centre of a span, the helicopter collided with the lower wire and plunged into the ground.

The helicopter was dropping incendiary bombs, from 100 feet above ground level, as part of a controlled bush burn. Prior to take-off the pilot had placed his flying jacket between the rear of the pilot's seat and the incendiary delivery machine.

During an incendiary dispatch run the exit chute became detached from the incendiary machine body allowing ignited bombs to fall inside the aircraft. One of these bombs set fire to the pilot's jacket and this along, with the burning incendiaries, filled the cabin with dense black smoke.

Despite the fact that the passengers opened their doors the dense smoke prevented the pilot from seeing anything either inside or outside the helicopter. He elected to land the aircraft immediately so the crew could extinguish the fire.

During the unsighted landing in dense scrub the helicopter collided with a number of trees.

It was reported that the clamp attaching the exit chute to the machine body had been secured normally prior to departure. The clamp design relied on friction only, to keep the chute in place. It is probable that natural helicopter vibration was sufficient to overcome the friction allowing the chute to separate. Once the chute separated, ignited incendiary balls were free to roll around inside the aircraft and set fire to the jacket.

The design of the incendiary machine did not include any means of restricting the movement of the incendiary balls should they fall out of the machine. It was believed that the balls, which were only armed after they had entered the delivery system, could not escape.

For the same reasons it was not believed that flammable material might be in danger if it was stored near the machine and consequently there were no restrictions and no placards prohibiting such storage.

Safety Action

Immediately following the accident, the Bureau of Air Safety Investigation advised the owner of the incendiary equipment that the following modifications would improve the safety of the system.

1. A clearly visible placard should be fitted to the incendiary machine indicating that objects should not be stored in its vicinity.

2. The chute attachment should be redesigned to make it more positive.

3. A fail-safe system be designed to catch loose incendiaries. It is suggested that a metal tray, with sides, located under the dispensing machine would probably meet all requirements.

The operator withdrew all similar incendiary dispensing devices from operations until the defects had been corrected. Redesign and modification of the devices has been completed, and the machines have been returned to service.

While conducting joy flights a misunderstanding made the pilot believe that a commercial requirement necessitated landing in the 25 direction, which had a 2 degree downhill slope. The first approach for landing was high, and a go-around was initiated from about 100 feet above ground level. The pilot reported that during the overshoot the aircraft performance was poor, failing to climb satisfactorily and passed close to the tops of a group of trees.

The next approach was still high and at a speed slightly faster than the published approach speed for the prevailing conditions. The aircraft floated for a distance after flaring and touched down late. Being reluctant to attempt another go-around, the pilot tried to stop the aircraft before the end of the airstrip, but it overran and continued down a steep slope, coming to rest in a ditch.

Witness reports indicate that although the wind at the time of the occurrence was described as a variable gusty crosswind, a certain amount of downwind component had previously been noticed.

Take-off was rejected when the pilot realised that the aircraft could only be turned to the left due to malfunction of the right brake assembly. Subsequent investigation revealed that the right brake torque plate had failed.

Metallurgical examination found that the torque plate had failed due to a fatigue fracture at one of the thru-bolt holes. The initiation and propagation of the fatigue crack had resulted from the lack of sufficient torque on the centre thru-bolt.

VH-IDZ was enroute Darwin to Kalkgurung, tracking via Victoria River Downs, tracking 174 degrees at the correct cruising level of 9500 feet. About 16km north of Victoria River Downs the pilot observed another aircraft pass directly under him in the opposite direction with a vertical separation of 100-200 feet.

The other aircraft, VH-AZO, was enroute from Tanami to Darwin via Victoria River Downs tracking 007 degrees and also cruising correctly at 9500 feet.

Changes made to Australian airspace, which replaced the quadrantal cruising levels with hemisphere cruising levels, allows opposing VFR traffic within the same hemisphere to operate at the same altitude.

The pilot reported that he made an approach to land on runway 32 at Corowa. He estimated the wind to be 320/20 with gusts to 35 kts. Final approach was made with full flap at 70-80 kts and wind gusts were encountered on final approach. The Pilot's Operating Handbook for the aircraft type recommends an approach speed of 65-75 kts with full flap and 70-80 kts with flaps up.

On touchdown the aircraft ballooned. The pilot advised that he continued to apply back pressure to the elevator and the aircraft landed again very heavily.

Significant Factors

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

1. Gusting wind conditions.

2. Approach speed too high.

3. The pilot did not take appropriate corrective actions after the aircraft ballooned after initial touchdown.

During take-off the crew noticed a small surge on the right engine torque indicator, with no noticeable power change. Shortly after lift-off, as the landing gear was retracting, the right engine torque suddenly increased to 107%. The power lever, although extremely stiff to move, was eventually retarded until the torque was reduced to 85%. By this time the auto coarsen system had commanded the propeller RPM to zero and the engine was shut down. The flight continued to Orange where an uneventful single engine landing was carried out.

Subsequent investigation revealed the right engine Beta tube had failed where it entered the Propeller Control Unit (PCU). The remains of the tube were jammed in the PCU, which was stiff to operate at the power lever input shaft.

Investigation by the manufacturer attributed the failure to localised pick up and seizure of the PCU Beta Sleeve to the Beta Tube Unit Sleeve, resulting from a reduction below the minimum diametrical clearance between the two components. This was due to an incorrectly formed undercut in the Beta Rack during manufacture, which prevented satisfactory location between the two components, and subsequent distortion of the sleeve.

The manufacturer has instigated an inspection requirement for Beta Racks from the same batch number and advised that future batches will be examined prior to assembly.

The pilot was taking his friends for a local flight. He commenced a take-off on runway 09 which has a gravel surface and is 423 metres long. When about two thirds of the way down the runway, the pilot realised the aircraft would probably overrun the end of the runway and collide with the boundary fence. He attempted to brake but realised it was too late, so he then attempted to fly the aircraft over the fence for a landing straight ahead in an adjoining paddock. However, the aircraft collided with the fence. After the accident, the pilot realised he had attempted to take off with a 15-knot tailwind. He believed that he read the windsock back to front.

VH-CZI was a substitute aircraft for VH-CZC which had been originally planned to operate the flight Sydney to Canberra.  Because no modification message had been originated, the Canberra aerodrome controller (ADC) was neither expecting a call from, nor held a flight progress strip (FPS) for, VH-CZI.

The Canberra approach (APP) controller, located in the Melbourne Area Approach Control Centre (AACC) since

July 1994 attempted a voice co-ordinated hand-off of VH-CZI to the ADC at approximately 30 nautical miles (NM) from Canberra.  The ADC was busy on another task at the time, so he instructed APP to standby.  APP terminated the Canberra call and dealt with other traffic co-ordination.  Although the hand-off of VH-CZI was not completed, the FPS was annotated as though the co-ordination had been completed, without restrictions imposed by the ADC.  APP continued processing VH-CZI for a visual right circuit for runway 35 at Canberra in the normal manner.  About this time there was a change of ADC personnel and neither the uncompleted co-ordination exchange nor the presence of VH-CZI entering the circuit area were noted.

APP then transferred VH-CZI to the Canberra ADC frequency, but the aircraft had a minor radio problem during the transfer which did not significantly affect the actual frequency transfer.  Subsequently, the first communication from the aircraft to the ADC was in the nature of a radio communications check, rather than a normal base report and was insufficient to cause any concern.  The call could have had its origins from the aircraft located anywhere within VHF range of the ADC frequency such as would occur from an aircraft within approximately 200 NM if overflying at high level. The initial radio check call was then followed by a call which alerted the ADC that VH-CZI was in fact on right base for Canberra runway 35.  Until that time, neither the former nor latter ADC had been aware of VH-CZI.

Hard copy departure (DEP) messages are required to be originated for all regular public transport (RPT) flights. Sometimes the DEP messages are delayed to the extent that voice co-ordination occurs first due to the short flight time involved between Sydney and Canberra.  On this occasion, a modification (CHG) message, advising of the aircraft substitution, should have been generated when first advice was received.  But this was not done, presumably because of either the short flight time intervals or the intention to include the CHG information in the DEP message. It is standard operating procedure (SOP) for APP to co-ordinate estimated times of arrival (ETA) to the ADC for all arriving aircraft with a flight time of 30 minutes or less, unless a hard copy message has been generated.

The SOPs also prescribe that inbound aircraft are transferred from APP to ADC at about 40 NM, where aircraft normally become visible on the ADCs non labelled radar display. In the prevailing visual conditions APP was required to obtain any restrictions for further descent for inbound aircraft from the ADC.  At the time of the incident, there was no standard phraseology indicating absence of a descent restriction.  This situation has since been rectified by the Civil Aviation Authority.

New technology radar facilities with jurisdictional label displays are programmed for commissioning in the Canberra control tower early in 1995. Provision of new radar facilities will not remove the necessity for failsafe transfer of jurisdiction SOPs between APP and ADC because of the requirements for the ADC to maintain continuous visual surveillance of circuit traffic.

CONCLUSIONS

Findings

1. A modification message advising of the aircraft substitution was not originated.
2. The approach controller terminated the co-ordination call and then incorrectly notated the flight progress strips to indicate that transfer of jurisdiction was completed.
3. Neither the uncompleted co-ordination nor the presence of the aircraft entering the circuit area were detected during the transfer of responsibilities between the aerodrome controllers.
4. The first communication from VH-CZI to Canberra tower was insufficient to alert the controller to the presence of the aircraft in the circuit area.
5. The standard operating procedures prescribed for jurisdiction transfers were not failsafe.

SIGNIFICANT FACTORS

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

1. There were inadequate back-up procedures to prevent degradation of system safety levels caused by delays or omissions in generating hard copy modification and departure messages.
2. The existing control tower radar display facilities and co-ordination procedures were inadequate to alert the controller/s to the inbound aircraft.

SAFETY ACTION

As a result of this investigation the Civil Aviation Authority has introduced standard phraseology for co-ordination exchanges where descent restrictions have not been imposed.

As a result of this investigation, the Bureau established that pending system changes by the Civil Aviation Authority would provide fail safe back-up procedures to prevent similar occurrences caused by delays or omissions in generating hard copy modification and departure messages.  The outcomes of the system changes would be monitored for effectiveness by both organisations.