At time 1831, 3 minutes after departure, a clearance was issued to the pilot of   VH-AJJ to track via Savoy and planned route with a climb to FL310.

No separation standard, i.e. 10 minutes or 1000 feet in altitude, was established between VH-AJJ and VH-JJQ.

At time 1839, VH-JJQ reported passing T84C at 1839, FL270, estimating Curtin at 1934. This transmission was made on the Perth Sector 2 (134.5) frequency.

At time 1843.5, the pilot of VH-AJJ reported maintaining FL310 and requested a higher level. VH-AJJ was now vertically separated from VH-JJQ.

The Controller was preoccupied with a separation problem in the vicinity of Karratha and did not fully assess the situation between VH-JJQ and VH-AJJ. It was also moderately busy at the time and a number of transmissions took place around the time of the incident. As a consequence of the workload, the Controller took the advice of the Sector 2 Controller who advised her to assign VH-AJJ FL310 due to SIA7220.

The Sector 2 Controller also entered a time when VH-AJJ would leave lateral conflict with SIA7220 on the flight progress strip for the Sector 1 Controller. This led the Sector 1 Controller to think that the Sector 2 Controller had looked at the entire scenario and offered a solution that would separate all the conflicting traffic.

The Sector 1 controller then issued a clearance to the pilot of VH-AJJ to climb through the level of VH-JJQ without fully assessing the traffic situation.

Factual Information

During cruise at FL250 in instrument meteorological conditions with light to moderate icing, the crew reported that the aircraft yawed to the left and the left engine ran down to about 4% torque then recovered in about 2 seconds. About 1 minute later the same problem occurred to the right engine. The pilot requested a descent to FL180 and disconnected the autopilot to hand fly the aircraft. About 30 seconds later both engines almost simultaneously suffered the same problem again. The crew carried out checks for erratic engine behaviour and requested a descent into Sydney for a precautionary landing. The remainder of the flight was uneventful.

Extensive ground checks revealed that neither engine had sustained damage as a result of the event. Flight Data Recorder information indicated that the first event occurred on the left engine when the torque fell to 26.4% with a loss of 1.8% RPM which recovered in about 4 seconds. One minute 24 seconds later the left engine again suffered a torque loss to 18.6% with a loss of 3% RPM recovering in about 3 seconds. About 30 seconds later the right engine suffered a similar event. Torque dropped to 18.7% with an RPM loss of 3.8% recovering in 3 seconds. These events occurred at FL250, and no further events were recorded.  Propeller and engine anti-icing were on at the time and continuous ignition was selected.

Information from the Bureau of Meteorology indicated that the aircraft was in light rain at the time and the water droplets were probably supercooled.

Analyses

Visual inspection of the aircraft revealed that both engines had an into-wind step where the inlet cowl fairs with the spinner (the engine cowl protrudes below the line of the spinner). The step on the left engine was more pronounced than the right. The manufacturer is of the opinion that an into-wind step in this location can result in the formation of ice which can interfere with inlet airflow and subsequently lead to ice ingestion. To rectify this problem the manufacturer has raised modifications and maintenance instructions.

Power recovery under these conditions is dependent on a fully serviceable ignition system. Either auto re-ignition or, if that system is unserviceable, continuous ignition must be selected.

The operator's Minimum Equipment List (MEL) provides for the aircraft to be dispatched with the auto re-ignition system inoperative. The system is then placarded inoperative and a procedure testing the continuous ignition system is carried out. This procedure requires observation of the flight deck lights for the L-IGN and R-IGN to ensure they illuminate. However, this procedure does not guarantee that the respective engine ignitors are operating.

CONCLUSION

Significant Factors

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

1. The aircraft encountered an area of supercooled rain.
2. Both engines have into-wind steps at the inlet cowl to spinner fairing which allowed the formation and probable ingestion of ice.
3. Engine power recovery was effected by the ignition system.

SAFETY ACTION

As a result of this investigation, it was determined that the integrity of the ignition system is paramount for instantaneous power recovery to the engine.

The Bureau has made the following recommendation R950102:

The Bureau of Air Safety Investigation recommends that the Civil Aviation Safety Authority amend all Jetstream J 4100 Minimum Equipment Lists to include an audible test of the engine ignitors to ensure correct operation prior to despatch with the auto re-ignition system inoperative.

At the time of taxi out, for a runway 03 take-off, ATIS Delta was current. This advised the surface wind was from 090 degrees, with a wind speed of 20 kts, gusting to 30 kts. The crew arrangements were that the first officer would fly the aircraft from the right hand seat.

Take-off clearance was given to the aircraft and then the tower controller advised the crew that the crosswind was 22 kts. On the take-off roll rotation was commenced as normal. However, the captain sensed the rotation rate then increased and put the palms of his hands on the wheel to try and reduce the rotation.

A brief tail skid strike occurred during lift off. After take-off the tail skid retracted normally. Crew radio discussion with maintenance staff followed and it was considered safe to continue with the flight.

Company policy was that first officers are subject to limitations on the strength of crosswind allowed for them to perform a take-off. In the first year of operations the first officer was limited to 15 kts. The first officer flying the aircraft had been approved to take-off with 20 kts of crosswind.

The captain reported that he had looked at the windsock and assessed the wind strength and considered it did not exceed 20 kts at the time of take-off. Following the incident, it was not possible to determine whether the crosswind had exceeded 20 kts. However, senior company flight personnel considered that the tower report of 22 kts crosswind should have been used for the captain's decision on who should have done the take-off.

Significant Factors

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

1. Significant crosswind component present during the take-off.

2. The captain probably made a judgement error in allowing the first officer to do the take-off.

3. An excessive rotation rate occurred during the take-off.

VH-NMA was en route from Perth to Meekatharra at 27,000 feet (FL270) and had passed position Mount Magnet at time 0810 and was estimating Meekatharra at 0831.

VH-FMQ departed Readys for Perth at time 0801 and was estimating Mount Magnet at 0819 and had planned at FL260.

In addition, VH-LBX was en route between Peakhill Mine and Perth. This aircraft had planned via Meekatharra (estimate 0825) and Mount Magnet (estimate 0848). VH-LBX was issued with a requirement to Reach FL240 by Meekatharra to facilitate separation with the other traffic.

At time 0813.5 a clearance was issued to the pilot of VH-FMQ to transit via planned route, to climb to FL220, and to expect higher levels at Mount Magnet.

At time 0816 an instruction was passed to the pilot of VH-NMA to leave control area on descent with a requirement to reach FL230 by time 0820. This was done to ensure separation with VH-LBX.

The pilot of VH-NMA queried the requirement and was told it was due to traffic. VH-NMA then commenced descent.

At time 0819.5, the pilot of VH-NMA reported leaving FL230 and requested the traffic.

The Perth Sector 4 Controller advised the pilot of VH-NMA that he could expect a short delay at FL230. The pilot queried this, stating he had just left FL220. The Sector 4 Controller then told the pilot of VH-NMA to report leaving FL210.

At time 0821, the pilot of VH-FMQ reported passing over Mount Magnet at time 0819, maintaining FL220.

The aircraft were now established on opposite sides of a Navaid and adequately separated.

The Sector 4 Controller had predetermined how to separate the aircraft involved, but gave the pilot of VH-NMA an

instruction to leave control area on descent, instead of limiting decent to FL230 to remain separated from VH-FMQ.

Prior to issuing the descent clearance, the Controller did not advise the pilot of VH-NMA of the plan to enable him to descend into Meekatharra without experiencing extensive delays. Had this been done it is likely the pilot of VH-NMA would have realised the error when he was given descent below FL230.

VH-FMQ passed over Mount Magnet at time 0819 which was the time that NMA reported leaving FL230, so although separation existed, the Controller was unaware of the fact.

The Controller was experienced and, at the time was also performing Team Leader duties.

A review of the flight strips indicated that no times of passing between the aircraft were recorded on the flight progress strips and other details missing indicated that the Controller was not performing at the required technical level at the time.

The traffic levels in Sector 4 when it is busy, particularly in the vicinity of Mount Magnet, may warrant a separate flight progress board bay designator for Mount Magnet. This would make it much easier to visualise conflictions than the current method where the Mount Magnet position is located adjacent to the Mount Singleton designator.

Safety Action

The Civil Aviation Authority are reviewing the possible use of a Mount Magnet designator on the flight progress board.

VH-TFB was inbound to Sydney from Canberra and had been instructed to descend to 5,000ft for an approach to runway 16R. At the same time, VH-WMY was inbound to Bankstown from the north, maintaining 3,000ft. VH-TFB was subsequently observed by radar to descend to 3,200ft, about 1 NM from VH-WMY. The pilot of VH-TFB was given traffic on the other aircraft and instructed to immediately turn left and climb to 5,000ft. This instruction was complied with promptly. The pilot of VH-WMY was visual between cloud layers and became aware of VH-TFB as it turned and climbed.

The pilot of VH-TFB later reported having been distracted whilst flying through a line of thunderstorms, associated with heavy rain and turbulence, and had inadvertently descended below his assigned altitude.

The pilot had been engaged in fire spotting. On returning to land he assessed the wind conditions, via the windsock and smoke drift, and proceeded to land into wind. On touchdown a wind gust caused the aircraft to drift to the right where it encountered soft soil. The aircraft veered further to the right until the leading edge of the right wing impacted the windsock pole.

Significant Factors

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

1. The aircraft encountered a wind gust on touchdown.

2. The aircraft encountered soft ground on the landing roll when it veered to the right.

The pilot had been engaged in sheep spotting and was returning to refuel when the engine lost power about 2km from the airstrip at a height of 500 feet. The aircraft was landed on a gravel road, but directional control was lost in the loose gravel, and the wings contacted some low scrub. When the nosewheel was lowered to the ground, the aircraft veered to the left, and came to rest on the propeller spinner, the nosewheel, and the right wingtip.

The fuel tanks were subsequently drained on site and yielded approximately 45 litres of fuel from the right tank. The fuel had drained from the left tank to the right tank because of the aircraft's attitude. The pilot said he had been airborne for 3.5 hours and using the consumption rate of 45 litres per hour, had calculated that he should have had 48 litres of fuel remaining when the engine lost power. However, he had not flown a Cessna 182A before, had not read the flight manual, and was unaware of the unusable fuel quantity. He had been flying a later model which had less unusable fuel.

The flight manual shows that the unusable fuel quantity is 37.7 litres, and useable fuel quantity is 208 litres. The pilot stated that the fuel selector was selected to both tanks (left and right) for the duration of the flight. During the flight the aircraft was turned frequently, and the direction of turn was predominantly to the left. This may have caused fuel to drain from the right wing to the left and allowed air into the system when the quantity fell below the lowest useable level.

The pilot of VH-CYT landed the aircraft on runway 35. On the landing roll he asked the tower for clearance to turn left into runway 12/30. Because another aircraft, VH-CSZ, was about to land on runway 12 the air traffic controller told the pilot of VH-CYT "negative, continue through the intersection without delay".

The pilot of VH-CYT misunderstood the instruction and turned left into runway 12/30. VH-CSZ had already been cleared for a touch-and-go landing on runway 12 and was already on the ground when VH-CYT turned left. The controller issued instructions to both aircraft to stop. They both came to rest on the runway, with about 350 metres space between them.

Significant Factor

The following factor was considered relevant to the development of the incident:

1. The pilot of VH-CYT misunderstood the instruction given by the tower controller.

The duty runways were 17 left (17L) and 17 right (17R). On arrival VH-USH joined upwind and made a full right hand circuit for 17R. VH-EOT was operating on circuits on 17L.

VH-USH was next observed on final for runway 13R. The air traffic controller for the 17R circuit told the pilot that if he could not land on 17R he should go around.

In response the pilot of VH-USH said he would be landing on 13R. The controller assessed that this could be safely achieved as VH-EOT was expected to be clear of the runway intersection by the time VH-USH touched down. VH-USH landed on 13R.

The pilot of VH-USH had been to Moorabbin only once before and this was a long time ago. During the right hand circuit, he inadvertently lined up on final on 13R. He realised his mistake late on the approach, about when the controller called. The other aircraft had been in sight, and he knew it would be clear of his landing path. The controller's instruction reference landing runway 17R was misunderstood in that the pilot thought he was allowed to continue landing on 13R.

Significant Factors

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

1 The pilot of VH-USH misidentified runway 13R as runway 17R.

2 The pilot of VH-USH misunderstood the instruction from the controller to go around if he could not land on 17R.

3 The pilot was not familiar with Moorabbin.

The crew of VH-YSB had flight planned for an examination flight test to be conducted in accordance with Japanese Civil Air Board procedures which required a practice instrument landing system (ILS) approach to a minimum of 200 ft above aerodrome elevation.  They had briefed for a left turn from the runway 35 minima at Canberra.

Due to equipment limitations at Canberra, air traffic control (ATC) had instituted a system of slot times for any pilot requesting a practice ILS.  The pilot of VH-YSB had obtained approval for such a practice ILS and had also advised ATC that he would be carrying out a Category One ILS.  As ATC had no special instructions relating to the words 'Category One' in the notification of a Category One ILS at Canberra, no further action was taken by them in relation to that part of the flight plan advice.  Their expectation was for VH-YSB to carry out a standard ILS to the normal published decision height of 330 ft above the aerodrome elevation. As far as ATC were concerned, this was the only minimum for this approach and the instructions issued to aircraft were based on the use of this minimum.

The Canberra runway 35 ILS is not approved for Category One operations. The Category One ILS is designed for landings in extremely poor weather conditions and requires additional ground facilities which are not yet provided in Australia.

The crew of VH-YSB were cleared for final by Canberra Approach and were instructed to contact the tower for further instructions, which they did.

VH-ILL had completed a solo training exercise to the north of Canberra and was being processed by the aerodrome controller (ADC) for a right circuit to runway 30.

The ADC was under training and being supervised by an appropriately rated training officer.  The pilot of VH-YSB requested a left break and left circuit from the ILS.  The ADC decided that because of the traffic situation, such a procedure was not appropriate and issued instructions for VH-YSB to make a right break at the minima and then conduct a left circuit for a landing on runway 30.  There was some confusion between ATC and the crew of VH-YSB at this point but a correct readback of the instructions was obtained.

The ADC had been assessing the situation in relation to a landing sequence between VH-YSB and VH-ILL.  He decided that VH-ILL would be number one and issued instructions to achieve this sequence.  Consequently, he re-issued the break instruction to VH-YSB but in so doing included the words 'at the minima or when ready'.  This was misinterpreted by the pilot as an additional approval to continue to a minimum of 200 ft as required by the company's examination procedures.

The ADC decided to add a further requirement for VH-YSB to remain south of the field at all times in the break as this would add an additional safety buffer between the two aircraft.  Although this instruction was issued, no readback was obtained from the pilot and the crew do not believe they received such an instruction.  Examination of the automatic voice recording indicates that the pilot and ADC were probably transmitting at the same time and did not receive each other's message.

VH-ILL had continued an approach to runway 30 in accordance with ATC instructions.  As VH-ILL was on final approach VH-YSB had commenced its go-around from a 200 ft and, realising that he would be unable to make a left circuit for runway 30, the pilot levelled the aircraft wings to overfly runway 30.  His intention was to make a right circuit contrary to the instructions from ATC.  The pilot believed that this was the safest course of action he could perform from his position and that this action would enable him to comply, as near as possible, with the last ATC instruction.

The ADC training officer realised that VH-YSB was not going to remain clear of the flight path of VH-ILL and immediately gave traffic information on VH-ILL to the crew of VH-YSB.  Because VH-ILL was crossing the threshold with a landing clearance and VH-YSB was climbing and seen to be above VH-ILL, the training officer decided that no further action was necessary to prevent a collision and re-cleared VH-YSB for a right base to runway 30.

The aircraft passed within 150-300 ft of each other.

The training manual in use by the flying school states that such flight tests will descend to 200 ft before commencing a break.  However, ATC instructions only refer to the published minima, in this case 330 ft.

The go-around instruction given by ATC was designed to be commenced by 330 ft and would provide sufficient room for a safe left circuit to runway 30. Both ATC and the crew of VH-YSB agree that the position of the aircraft at the commencement of the break did not permit a safe execution of this manoeuvre.

The phrase used by the ADC, 'at the minima or when ready', was designed to allow a pilot to commence the break earlier than the minima if an easier transition to downwind leg was required.  However, in this occurrence it only served to reinforce the pilot's belief that he could continue to 200 ft.

Findings

1. The flying training school's advice to ATC of a Category One ILS approach had no meaning to the controllers.
2. There were no ATC instructions referring to runway 35 ILS approach minima below 330 ft.
3. The Canberra runway 35 ILS approach is not approved for Category One operations.
4. The crew of VH-YSB continued below the published minima for the approach being used.
5. The company training manuals used by the crew of VH-YSB specify a Decision Height of 200 ft for this particular examination.
6. The company training manuals used by the crew of VH-YSB had been accepted by the Civil Aviation Authority.
7. The go-around instructions issued by ATC were not able to be safely complied with from 200 ft.
8. The phraseologies used by ATC in issuing overshoot instructions were confusing to the crew of VH-YSB.
9. The ATC requirement for VH-YSB to remain south of the airfield in the right break was not received by the crew of VH-YSB.
10. The ADC was unable to provide adequate visual separation.
11. A breakdown in separation standards occurred.

Significant factor

The implications of the notification of a CAT 1 ILS by the flying training school, had not been disseminated to ATC.

Safety Action

As a result of the investigation:

1. ATS management at Canberra reviewed and amended the phraseologies in use at Canberra for overshoot instructions in similar circumstances.
2. The flying training school has reviewed and amended its notification requirements for ILS training flights.