On rotation for take-off the crew heard a noise. As landing gear retraction was normal and the aircraft continued to operate normally the flight was continued. The aircraft had reached about 220km from Darwin when the crew were advised by a company ground engineer that a section of main gear tyre tread had been found on the runway. The Captain briefed the crew for a possible emergency landing and the flight continued to Brisbane where emergency services were put on standby.

A safe landing was made and the aircraft taxied to a parking bay where investigation revealed that the right hand inboard tyre tread had separated, causing damage to the landing gear door clamp. The tyre was a level 6 retread (having been re-treaded 6 times), the occurrence being similar to earlier problems with this make of tyre. The company removed all re-treaded tyres above the level 4 retread status for inspection.

Simultaneous runway operations were in progress at Sydney when VH-MJH was cleared to land on runway 34, with a requirement to hold short of runway 07. After the aircraft had landed the aerodrome controller (ADC) instructed the pilot to take the first available taxiway to the right. This was taxiway 'Hotel', located about 238m from the runway 07 simops lights. VH-RMN, a Boeing 727 which was lined up on runway 07 was then cleared for take-off. VH-MJH was then observed to have passed the taxiway and was told to hold short of runway 07. The aircraft continued rolling and when the ADC became uncertain that the aircraft was going to stop before runway 07, he instructed the aircraft to stop.

The aircraft did not stop, and the ADC then cancelled the take-off clearance for VH-RMN which was now rolling for take-off. Another aircraft was sent around from a 2-mile final approach for runway 07. VH-MJH came to a stop mid-way between the stop lights (holding point) and the edge of runway 07. After VH-RMN had stopped VH-MJH was cleared to cross runway 07 and vacated runway 34 on taxiway Bravo 6. The first officer was the pilot flying VH-MJH until after the aircraft had touched down. The captain then took the controls during the landing roll, and the first officer turned his attention to the after landing checks. The captain stated that he had not heard the transmissions to stop.

It was not until he noticed that the first officer was transmitting that he realised that he was not monitoring the tower frequency. After he had received a landing clearance, he had intended to deselect the company frequency and had inadvertently deselected the tower frequency. The first officer had subsequently acknowledged the transmissions from the tower and was not aware that the captain was not monitoring the tower transmissions. The first officer realised that the captain was not following the towers instructions when the aircraft passed the taxiway and he instructed the captain to stop using both verbal and visual signals. By this time the aircraft was nearing the runway intersection.

The captain misidentified the position of taxiway Hotel due to the position of a large mound of earth which had previously been located south of runway 07, but which was now located north of runway 07. This gave him a false impression as to the location of the taxiway and was not aware that he was approaching the runway until after it was too late to stop before the holding point lights.

Significant factors

1. The captain inadvertently deselected the tower frequency just prior to taking control from the first officer.

2. After handing control of the aircraft to the captain, the first officer diverted his attention to the after landing checks.

3. There was a breakdown in crew co-ordination procedures.

The student was making a practice glide approach to land, with the throttle in the closed position. Sink developed late on the approach with the airspeed reducing, and full power was applied. The aircraft touched down about two metres short of the sealed surface in a soft area. As the aircraft rolled forward the wheels contacted a 'step' at the start of the sealed area. The contact with the 'step' collapsed the main gear legs and the aircraft slid to a stop.

Significant Factors

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

1. The pilot under supervision misjudged the approach.

2. The instructor was late in assessing the situation and did not ensure power was applied in time to correct the sink rate and descent path.

The nose gear collapsed on touchdown. The repair organisation was unable to find any mechanical fault that would have allowed the nose gear to collapse. Later advice was received that during a crosswind landing, the pilot allowed the aircraft to touch down on the nosewheel while the aircraft was yawing to the right.

Qantas 10 was one of four south-east bound aircraft estimating overhead Curtin reporting point at approximately 0000 WST. Lauder Air 2 was north-west bound and estimating Curtin at approximately 0100 WST. Several other aircraft were also due to enter the airspace around Curtin during this period. Lauder Air 2 was maintaining FL350 (35,000 feet). Qantas 10 was maintaining FL310 and had requested FL370. The duty Air Traffic Controller (ATC) cleared Qantas 10 to climb to FL330, at Curtin, with an expectation that a clearance to FL370 would be available later. The complexity of the traffic situation required the duty ATC to co-ordinate traffic with Melbourne Sector and to make a number of calculations associated with the "time of passing" between Qantas 10 and other aircraft.

During this process the ATC, incorrectly, wrote the "time of passing" between Qantas 10 and another aircraft on the Lauder Air 2 flight strip. The correct "time of passing" between Qantas 10 and Lauder Air 2 was 0029 but the duty ATC wrote 0047 on the Lauder Air flight strip. A "time of passing" of 0047 was also entered on Qantas 10's flight strip. Following advice from Melbourne, at 0026, that Qantas 10 would be accepted at FL370 the duty ATC checked the "time of passing" written on the flight strip (0047) to ensure that sufficient time for the climb was available, (ten minutes for the climb and ten minutes for the buffer), and cleared Qantas 10 to climb to FL370. As Qantas 10 commenced climbing the crew observed the lights of Lauder Air 2 directly ahead. Qantas 10 stopped its climb at FL340 and reported the situation to the duty ATC who then instructed Qantas 10 to descend again to FL330. Lauder Air 2 passed directly overhead and 1500 feet above Qantas 10.

The investigation determined that the duty ATC, who was assessed as very experienced and competent, had also made other procedural errors during his time at the console. Evidence was available which indicated that the errors were probably the result of accumulated fatigue brought on by a lack of sleep and disrupted sleep patterns, a lack of adequate rest breaks over both the long and the short term and pressure caused by the additional tasks associated with his position as a Team Leader.

The aircraft was on a test flight following maintenance. The pilot called Cairns Approach for clearance and a clearance instruction was issued. However, no acknowledgement of the clearance was received, and the aircraft did not appear on radar when expected. When further attempts to contact the aircraft failed, search and rescue action was initiated. Approximately 40 minutes after radio contact with the aircraft was lost, the pilot telephoned Cairns Tower advising that the aircraft had suffered a communications system failure (including the transponder) and that he had landed at Cairns after following the loss of radio procedures.

Investigation revealed that there had been a failure of the Cairns Approach primary radar around the time communications with the aircraft were lost. Cairns Approach was not aware of the failure and saw neither a primary, nor a secondary return from the aircraft on the radar displays. The Cairns Tower controllers were conducting a visual search in the expected approach sector of the aircraft and did not see it land. Primary returns are represented by a small cross which appears in the centre of the circular symbol representing the aircraft. The disappearance of this cross was the only indication to the controllers that the primary radar had failed.

The size of the cross is such that its disappearance might not be noticed unless close attention was being given to that particular part of the radar display.

Then factors considered relevant to the development of this occurrence were:

1. The aircraft suffered a communications system failure which included the transponder.

2. There was a failure of the Cairns Approach primary radar of which the controllers were not immediately aware.

Safety Action

A SADN was submitted shortly after the incident concerning the primary radar failure and recommending the fitting of an alarm system to alert controllers of a primary radar failure.

The pilot reported that during cruise he experienced a loss of engine power associated with rough engine operation. He carried out a precautionary search and landed in a paddock. After landing, the engine was test run and could not be faulted. The pilot, having assessed that the available take-off length and surface conditions were adequate, elected to fly the aircraft from the paddock. The aircraft became airborne later than expected and struck a fence. A landing was made in the paddock immediately past the fence.

The crew of VH-NSD received an amended clearance on the flight from Townsville to Mackay, which required tracking over Proserpine. They experienced difficulties receiving the Proserpine VOR (VHF OMNI Range), in that the aircraft indications on both receivers were not indicating a steady reading. The pilots averaged the indications, but when they transferred to the Mackay VOR, they found that their aircraft was on the 300 degree radial and not the 311 degree radial as cleared by air traffic control.

The aircraft was then cleared to continue inbound on the 300 degree radial. Another aircraft was outbound on the 285 degree radial at the time and a breakdown in separation had occurred. The aircraft were estimated to have come within 8nm (15km) of each other.

The crew of VH-NSD did not report their inability to navigate accurately using the Proserpine VOR. This would have allowed air traffic control to use another means of separation other than confining the aircraft to radials. Mackay Air Traffic Control reported that the Proserpine VOR has not been reported as unserviceable by any other aircraft prior to or after this occurrence.

Two aircraft had departed runway 35, and VH-SLW had commenced a take-off. On reaching about 50 knots the pilot noticed the lights of VH-JMZ on final approach for runway 17 at about 200 feet above ground level. The pilot of VH-SLW stated that he expected the pilot of VH-JMZ to carry out a missed approach, and although his immediate reaction was to abort the take-off, he decided to continue as the aircraft was accelerating rapidly and going too fast to safely vacate the runway.

The pilot of VH-JMZ executed a short field landing and stopped short of the runway 08 intersection. VH-SLW became airborne and passed over the top of VH-JMZ at about 90 knots and 80 feet above the runway. The pilot of VH-JMZ acknowledged a taxiing call from VH-SLW when he was mid downwind for runway 17, but the pilot of VH-SLW did not hear this acknowledgement and was unaware of the presence of VH-JMZ. The second pilot in VH-SLW was not monitoring radio transmissions at the time.

The orientation of the aircraft prior to entering the runway was such that the pilots in VH-SLW were unable to see the downwind leg of runway 17 before they lined up. A review of the ATS tape recordings show that the pilot of VH-SLW did not make a radio transmission to advise traffic that he was lining up on runway 35 or that he was beginning his take-off roll. While on downwind for runway 17, the pilot of VH-JMZ had communicated with Cessna 210 VH-APU which was departing from runway 35, so that separation could be maintained with this aircraft. Once VH-APU was clear the pilot of VH-JMZ continued his approach, with the expectation that the runway would not be occupied

 After advising VH-SLW that he was mid downwind, the pilot of VH-JMZ did not transmit his position in the circuit. Just before landing he questioned the actions of the pilot of VH-SLW. The pilot of VH-JMZ reported that when he first saw VH-SLW on the runway he thought the aircraft was back-tracking and would vacate the runway but then realised that the aircraft was in fact taking off towards him. He believed that he was committed to land and could not carry out an overshoot once below 400 feet. He was aware that VH-SLW was occupying the runway when he landed.

Significant Factors

During the landing and take-off sequence of VH-JMZ and VH-SLW, the pilots placed their respective aircraft in a risk of collision situation.

Safety Action

Deficiencies identified during this investigation, including operational practices at uncontrolled aerodromes, are being analysed in conjunction with other occurrences in order to formulate appropriate safety actions.

The pilot requested, from Sydney Flight Service International, the NOTAM status of R674. The Flight Service Officer (FSO) checked the status using the FISOR system and advised that the area was not active. R674 is a military restricted area and is active on a 24-hour basis, any change to this status is advised by NOTAM. When the FSO checked the system, he received a message which indicated that there were no current NOTAMs for R674.

The correct interpretation of this message is that the area would still be active. Apparently the FSO, who was not familiar with the normal status of the restricted area, assumed that if no NOTAMs were current for the area, then it was not active. He should have advised the pilot that there were no current NOTAMs for R674. Significant factors 1. The Flight Service Officer made an incorrect interpretation of the message on the FISOR system.