Hudson 587 [HS748] was proceeding on a flight from East Sale to East Sale via Dubbo at Flight Level [FL] 170. While under the control of Melbourne Sector 2 the pilot requested a climb to FL190 and a diversion east of track for weather avoidance. The request was approved by air traffic control who then co-ordinated the changes with Sydney Flight Information Service [FIS] 6 as the track would take the aircraft outside controlled airspace [OCTA] for 8nm before entering Sydney Sector 6 airspace.

Some confusion arose as to which FIS position was responsible for the airspace because officers were still unfamiliar with recent boundary changes. The FIS 6 position was the wrong position to which to direct the co-ordination as FIS 2 had responsibility for that portion of airspace. The FIS 6 operator misjudged the actual track of Hudson 587 believing that the aircraft would remain in controlled airspace and, as such, the Melbourne Sector 2 controller would co-ordinate directly with the Sydney Sector 6 controller. On that basis the FIS 6 operator decided that no further action by him was required.

The Melbourne Sector 2 controller, although co-ordinating with the wrong FIS, instructed Hudson 587 to call Sydney on the correct frequency, which the crew did. The FIS 2 operator heard the call but was not expecting the aircraft as no co-ordination had been received by him. He immediately commenced co-ordination checks with Melbourne Sector 2, FIS 6 and Sydney Sector 6 to establish the current status of Hudson 587. Finally, Sydney Sector 6 issued an airways clearance for Hudson 587, but, as the aircraft was only OCTA for approximately three minutes, the clearance was not issued in time to prevent Hudson 587 penetrating controlled airspace without a clearance.

Significant Factors

1. The co-ordination procedures for the revised airspace boundaries were not adequately documented.

2. The Melbourne Sector 2 controller co-ordinated with the wrong FIS operator.

3. The FIS 6 operator miscalculated the track of Hudson 587.

4. The FIS 6 operator did not co-ordinate the position of Hudson 587 after accepting the report from Melbourne Sector 2.

5. There was no breakdown in separation.

Circumstances

The Canberra air traffic control approach and departures functions were being performed by one controller because of the low traffic density. VH-ILL departed Canberra for the local training areas and intended to transit at 4,000 feet which was the normal altitude for such transit. The approach/departures controller had a flight progress strip and notated this altitude on the strip in the normal manner.

The pilot of VH-ILL then requested a climb to 5,000 feet which was approved as there was no conflicting traffic. The flight progress strip was annotated correctly with this change.

At this time air traffic levels were increasing and it was decided to separate the approach and departures functions. During this transition, control of VH-ILL was taken over by the oncoming departures controller who was given the flight progress strip. The approach controller then replaced this conflict alert tool with another, a red plastic rectangle referred to as a "shrimp boat", which was placed on the radar screen to indicate that there was traffic en route to the training areas. However the controller did not notate an altitude on this shrimp boat.

VH-TAH was arriving at Canberra from Sydney and the approach controller was radar vectoring that aircraft for an approach to runway 35. During this vectoring process the controller descended VH-TAH to 5,000 feet without providing horizontal separation with VH-ILL. The radar screens at Canberra do not show Secondary Surveillance Radar [SSR] Mode C altitude readout, and the controller evidently forgot the height of VH-ILL.

The aircraft came within half a nautical mile and 300 feet of each other. The required separation standard is five nautical miles or 1,000 feet.

Significant Factors

1.The approach controller gave up his main conflict alert reminder when he passed the flight progress strip to the oncoming departures controller.

2.The approach controller did not notate the altitude assigned to VH-ILL on the red shrimp boat.

3. SSR Mode C altitude information is not available at Canberra.

Safety Action

Deficiencies were identified during this investigation and appropriate safety recommendations are being formulated.

The right engine failed on descent into Devonport. The engine was shut down and the aircraft landed without incident.

The engine was disassembled, and it was found that the gas generator second stage cooling plate had disintegrated. Extensive foreign object damage had affected the remaining components of the gas generator turbine.

Failure of the second stage cooling plate was a problem known to the manufacturer. A modified plate of improved durability had been introduced by SB72-352. The failed unit was of pre-modification status. As well as progressive introduction of the improved plates into the fleet when the engines are overhauled, the area is subject to regular borescope inspections.

The pilot said that after he had reported ready for take-off at the holding point for runway 11 centre, he was told that there would be a 5-minute delay in obtaining an airways clearance. After about 10 minutes he was advised that he could depart Bankstown, remaining outside controlled airspace (OCTA). He decided to proceed because he was obstructing other traffic.

The aircraft was observed to track directly through the centre of restricted area R505 which was activated. Mode C radar readout showed the aircraft on climb to 3000 feet, confirming that the pilot had penetrated the restricted area and the control area without clearance.

The pilot said he was unfamiliar with Sydney airspace boundaries and had Jeppesen charts for reference. He said in hindsight he should not have departed under the circumstances but decided to do so as he felt he was impeding other traffic on the ground at Bankstown.

At 1155 hrs VH-CEB reported inbound at the 2RN reporting point on the circuit training frequency 123.6 Mhz. The pilot was instructed to call on 132.8. He was then told to enter the circuit on crosswind for runway 29. Approximately two minutes later the pilot was asked for his aircraft type. He reported that he was an Arrow and that he was on crosswind. At that point the Aerodrome Controller (ADC) responsible for the training circuit informed the other ADC that VH-CEB was infringing the circuit and was at approximately 1000 feet.

VH-CEB was then instructed to turn left and enter right crosswind. The pilot replied that he was already on crosswind and that he was unfamiliar with Bankstown. VH-CEB was then instructed to overfly midfield and join for a right circuit on crosswind. The pilot of VH-IAD, a PA38 which was in the training circuit at the time, advised later that VH-CEB had come in close proximity to him.

The pilot of VH-CEB stated that this was only his second visit to Bankstown.

Significant Factors

1. The pilot of VH-CEB was unfamiliar with circuit procedures at Bankstown and misunderstood ATIS information.

As the aircraft became airborne at Adelaide Airport, air traffic controllers observed a tread separating from a main landing gear tyre.

The pilot was advised and confirmed an abnormal landing gear indication. Most of the tread of a main gear tyre was found on the runway and emergency services were placed on full alert.

The aircraft was operated clear of the circuit to reduce landing weight and to allow emergency services to be made ready. Later, after an inspection fly-past was carried out, the aircraft landed safely.

There have been other tread losses from the same type of re-treaded tyre. As a result, the operator has reduced the number of times this type of tyre will be re-treaded and has also stopped the purchase of this type of tyre.

The pilot reported that Melbourne Control had instructed him to call Melbourne on 126.0 Mhz at Yass, which he did. He was not aware at the time that this frequency was in fact a Melbourne Flight Information Service (FIS) frequency. The aircraft was at Flight Level 180, in controlled airspace. As a result, communications between ATC and the aircraft were disrupted, during which time the aircraft commenced descent without a clearance. The pilot should have called Melbourne Control on 126.6 MHz.

It was determined that the correct frequency was passed to the flight crew.

On selecting gear down at 130 kts, two loud bangs were heard from the vicinity of the right hand wing root. The nose gear down indicator light was illuminated but no lights were present for the main gear and the landing gear motor was still running. Emergency extension procedures were carried out with no change to the indications. On landing, the left main gear collapsed.

Engineering examination has not been able to determine the cause of the landing gear failure.

The aircraft was being radar vectored, heading 105 degrees, for an approach to land on runway 34 at Melbourne Airport. The Air Traffic Controller issued an instruction for the pilot to turn onto heading 080. In response the crew read back 010, but the controller did not detect this error.

Observing the aircraft on a near north track the controller asked the pilot to confirm heading 080. In response the crew said "affirmative," instead of reading back the assigned heading. Suspecting a compass failure the controller told the crew to turn right, intending to stop the turn when the aircraft was on an easterly heading. This turn was not made.

Following further communications, the aircraft was radar vectored and positioned for a visual approach on runway 34. A normal landing followed.

Significant Factors

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

1. The crew misunderstood the heading given to them by the approach controller.
2. The controller did not detect the error in the crew read back of the new heading.
3. When asked to confirm heading 080 the crew incorrectly replied "affirmative," instead of stating the actual heading.

The aircraft had been cleared for a visual approach to runway 23 at Adelaide via the Quarry turning point, with a request to maintain best possible speed on descent due to following traffic. Subsequently, the aircraft was observed to overfly Quarry towards the aerodrome at RAAF Edinburgh and was vectored, by air traffic control, to join the final approach path.

The crew of the aircraft advised that they were aware of their mistake and suggested that a higher-than-normal descent speed had caused them to overshoot the turning point.

There was no confliction with any other aircraft.