A Cessna 152, VH-XPG, was sequenced for landing on runway 12 at the same time as a Boeing 747, VH-EBY, was sequenced for runway 15. A separation breakdown occurred when both aircraft converged towards their respective runways and the Cessna 152 was instructed to go around.

The approach radar controller had previously co-ordinated the landing of XPG on the non-duty runway 12. The aircraft's position in the landing sequence had not been determined, but would be close to that of EBY. From the aerodrome controller (ADC) position, XPG was radar observed just inside 4 NM final for runway 12 as the pilot of EBY contacted the tower at 6 NM final for runway 15. XPG was not on tower frequency; the expectation being that the aircraft would sequenced (by approach) to land behind EBY.

With EBY at approximately 2 NM final, XPG was continuing the approach at approximately 1 NM final and the pilot was not yet in contact on the tower frequency. An attempt was made to establish whether the pilot of XPG was on the tower frequency, and this proved negative. Instructions were then issued to the approach controller to send XPG around immediately. Traffic advice was issued to the pilot of EBY as the pilot of XPG made the missed approach.

The approach controller did not ensure that separation was maintained between EBY and XPG when the latter was cleared to leave the western VFR route on a visual approach for runway 12.

The approach controller should have arranged for the provision of visual separation by the ADC or issued instructions to establish and maintain lateral separation between the two aircraft prior to radar separation reducing to less than the standard of 3 NM.

The controller did not appreciate the implications for maintenance of separation when he cleared the pilot of XPG to track for final for runway 12 and to make a visual approach. The controller became distracted with other traffic considerations and did not maintain an adequate scan of the radar display. The flow controller had been advised of the inclusion of XPG in the traffic sequence.

The flow controller was satisfied that XPG could be included in the traffic sequence without detriment to other aircraft; subject to the approach controller providing final sequencing. The approach controller did not ensure that adequate separation and sequencing was applied between the two aircraft.

Cairns ATS is developing amended flow/sequencing instructions which will include procedures for aircraft arriving to either runway 15 or12, or the runways concurrently.

This was the first occasion on which the pilot had sprayed the sugar cane paddock. A briefing and an area map were obtained from the property owner. The pilot conducted a power line inspection and found three lines, all that had been brought to his attention. During the first spray run he noticed sparks at the propeller as an unseen set of three wires was cut. He returned to the take-off point and found that only the propeller had been damaged. The wires struck had not been seen at all. The relevant poles were hidden in trees on each side of the paddock.

The aircraft was conducting an ILS approach to Townsville, which was under the influence of Cyclone Justin, centred about 180 km north. Weather conditions for the approach were a strong, gusting crosswind, moderate to severe turbulence, and heavy rain.

At the start of the approach the aircraft was high on the glideslope. As the approach progressed the aircraft descended until it was well below the glideslope. The first officer called the flying pilot's attention to the rate of descent, which was up to 3,000 ft/min. A short time later, when the aircraft was at 780 ft above ground level, about 500 ft below the glideslope, and with a descent rate of 2,000 ft/min, the first officer called for a go-around. The captain applied power, and the descent was stopped at about 700 ft above ground.

The aerodrome controller cleared the aircraft to climb to 3,500 ft for a further approach. However, the aircraft levelled initially at 4,000 ft before a descent to 3,500 ft was carried out. The aircraft landed off the second approach, conducted using the autopilot coupled to the ILS.

Following the take-off with 850 L of chemical for another spray task, the engine began to vibrate and lose power. The pilot dumped the load and conducted a forced landing into a paddock about 4 km from the departure airstrip. During the landing one main landing gear leg was torn off, the wings were creased, and the propeller was bent rearwards. After an examination of the engine the pilot found that the number 6 cylinder had cracked between the spark plug holes.

The helicopter was in a steady cruise at 80 kts at 1,500 ft above ground level when the pilot heard a loud bang. He immediately initiated auto-rotation and believed that there had been a failure of the tail rotor drive. The pilot attempted a landing in the nearest clear area but the nature and slope of the terrain coupled with some rotation of the helicopter resulted in it rolling over and sustaining severe damage during the landing.

Examination of the helicopter revealed that the intermediate flex plate failed. This flex plate consists of the front and rear yokes plus the flex plate itself, all joined by four bolts. The examination found that one of the two front lugs was missing. The adjoining flex plate lug was present and bent forward. The bolt joining the missing front yoke lug to the adjoining flex plate lug was also not present. Neither the bolt nor the front yoke lug were found at the accident site.

The hole in the flex plate lug, opposite the missing front yoke lug, was worn and enlarged suggesting that, after the bolt was liberated, the shaft's axis of rotation changed. Such an event would have led to failure of the tail rotor drive and given the symptoms described by the pilot.

The pilot had conducted a brief pleasure flight. He intended to land to the west on a 330 m grass airstrip on his own property. The strip ran east west with a 12.5 degree upslope to the west. He estimated the wind components to be 5 kt headwind and 15 kt crosswind. However, on short final, the aircraft encountered moderate turbulence and windshear. The pilot elected to overshoot, but because of the steep upslope, this required a turn north or south. He advised that from past experience in PNG, having landed on many bush strips, he would normally have turned into wind during an overshoot into a one-way uphill airstrip. However, on this occasion he inadvertently turned downwind and encountered more windshear and loss of airspeed.

With the aircraft facing downwind and very low in airspeed, he elected to land straight ahead in the paddock. During the latter part of the landing roll the aircraft nosewheel collided with a rock and the aircraft overturned. 

The pilot subsequently advised that the aircraft had recently undergone a complete overhaul and that had not contributed to the accident.

After completing pre-take-off checks in the northern runup bay for runway 29, the pilot of the Cessna 180 began taxying to the runway 29R holding point. As the aircraft moved forward and turned left onto taxiway K5 he saw a Piper Seneca to his right, in very close proximity, taxying along K5. The pilot of the Cessna braked sharply, however the nose of the aircraft pitched down, resulting in the propeller of the Cessna striking the left tailplane of the Seneca.

Weather conditions were fine, with no obstacles to visibility. Because of the high nose attitude of the aircraft and associated obstruction by the instrument panel, the pilot of the Cessna 180 did not see the approaching Seneca as he left the holding bay. When he did see the Seneca, he had insufficient time to prevent a collision.

The pilot reported that on departure from Coconut Island when he retracted the gear he heard an abnormal clunk. The gear unlocked light extinguished, but the pilot noticed that the aircraft was 10 knots slower in cruise indicating that the gear doors were not fully closed. On arrival at Horn Island the gear was selected down and there was no down indication for the left main gear. The pilot recycled the gear twice, changed gear indicator globes, tried sideslipping, and followed all procedures set out in the Emergency Checklist for failure of the main gear. A 500 ft flight over the airport and inspection from the ground confirmed all three wheels were extended but it could not be confirmed if they were locked. The pilot commenced an approach to runway 08 after emergency services were in place. After touchdown the left gear collapsed, and the aircraft came to rest off the left side of the runway but within the flight strip. The left gear retraction rod had failed during gear retraction at Coconut Island.

The flight was being conducted as a command check of the handling pilot, who occupied the left control seat. The pilot in command was the non-handling pilot. During an asymmetric circuit, with the left propeller feathered, the landing gear was lowered on mid-base at a height of about 600-700 ft. Because of the aircraft configuration, primary attention was given to the approach path while awaiting the build-up of the landing gear down-line hydraulic pressure.

At about 400-500 ft, the hydraulic landing gear lever was returned to the neutral position after both pilots confirmed the landing gear down-line pressure was above 500 PSI. The landing gear latch lever was then moved from the spring lock to the positive lock position without having first monitored the green landing gear light. The handling pilot called for the final flap setting (3/4 flap) as the aircraft descended below the 300 ft commit height, below which a go-around would not be attempted. Having made the final flap selection, the non-handling pilot then checked the green light, and the landing gear down-line pressure for 500 PSI minimum.

He noticed that the red unsafe landing gear light was illuminated but had experienced this situation before, with a red light showing and the landing gear warning horn sounding (the warning horn on this occasion was not operating). He assumed that the problem was due to a micro switch and felt that a safe landing could be made if the landing gear pressure was kept above 500 PSI, and the brakes used gently. The decision was made to continue to land after visually checking that the right landing gear was down. A lack of time and the state of the left sliding cockpit window did not allow for a visual check of the left landing gear.

Consideration was given to raising the latch lever and moving the hydraulic lever to "crack" the landing gear, and then selecting down again to re-lock. However, the aircraft was approaching the threshold, and the pressure was above 500 PSI with the landing gear hydraulic lever in neutral. On touchdown, the pilot in command observed the pressure at 500 PSI and immediately pushed the hydraulic lever down to keep the pressure up. This enabled the aircraft to roll the length of the runway, slowing to walking pace. During the final roll out, the flaps were selected up, resulting in the right landing gear very slowly retracting. As this occurred, the handling pilot closed the right mixture control. The propeller was almost stationary as the aircraft settle onto one blade.

A post-flight inspection found that the right landing gear spade lock had been locked out before the landing gear had completed the extension cycle. This action prevented the hook on the extension jack from engaging the spade lock and closing the micro switch. The action of retracting the flaps whilst the landing gear hydraulic selector was down, allowed hydraulic pressure to bleed from the landing gear down line, resulting in inadvertent retraction.

FACTUAL INFORMATION

A Boeing 767 (B767) aircraft departed Perth for Melbourne on climb to the flight planned level of flight level (FL) 370. The aircraft was being controlled by Melbourne Sector 1. This position was a procedural control position which used flight progress strips (FPSs) to manage aircraft separation. A number of FPSs were required for each aircraft under control. The FPSs designated the planned route of an aircraft.

After reporting at RERON, a position southeast of Perth, the crew requested a change of level to FL330. The change of level was approved by the Sector 1 controller. The controller annotated the new level of FL330 on the B767's FPSs.

While the Sector 1 controller was receiving coordination on three other aircraft from Perth Flight Service the crew of the B767 requested a change of level to FL350. The Sector 1 controller approved the change of level and then completed the coordination. The controller did not annotate the B767's RUFLE position FPS, the last FPS for the aircraft, with the amended level. This FPS indicated that the B767 was to operate at FL330.

The Sector 1 controller transferred the B767 to Perth Flight Service (FS) to maintain communications via High Frequency (HF) radio. The FS operator passed the B767's RIDLE position to the Sector 1 controller after the crew reported at that position. The aircraft's level of FL350 was reported to, and correctly read back by the Sector 1 controller.

The Sector 1 controller was then relieved at the position by another controller. The two controllers conducted a handover/takeover of the position. The relieved controller could not remember conducting a final check of the FPSs, as was his normal practice, before leaving the position.

The crew of the B767 reported to the new Sector 1 controller that the aircraft was now back on Very High Frequency (VHF) radio and was at position ROMPA at FL350 at 54 (time 1754 UTC). The Sector 1 controller coordinated the position report to Adelaide Sector 4 but read the level of FL330 from the RUFLE FPS. The Adelaide Sector 4 controller read back and annotated the B767 FPS with FL330. During this coordination sequence the Sector 1 controller was interrupted by a transmission from another aircraft.

The crew of the B767 subsequently transferred to Adelaide Sector 4 and reported at RUFLE at FL350. There was no breakdown of separation.

Sector 1 was combined with Sector 5. Traffic was light and less than normally experienced at the position for the time of day. The first controller had worked until 1300 ESuT that morning and then returned for the evening "Doggo" shift at 2300. He had two hours sleep in the afternoon and felt rested. He operated the position from approximately 0300 to 0445.

ANALYSIS

There were two opportunities to correct the error after the relieving controller assumed responsibility for the position. The first being when that controller started operating at the position and the second when the crew of the B767 reported at ROMPA at FL350. However, the incorrect annotation on the RUFLE FPS was not detected.

The reason for these errors not being detected or why the first controller did not annotate the RUFLE FPS could not be ascertained. It was probable that the physiological effects due to the early time of day and the low level of activity combined to reduce the controllers' vigilance and/or use of standard practices.

SIGNIFICANT FACTORS

1. The Sector 1 controller did not annotate all the B767 FPSs with the approved level of FL350.

2. The relieving controller did not detect the error in the RUFLE FPS during or after the handover/takeover.