Shortly after take-off, the pilot advised ATS that aircraft operation was abnormal and he was returning to Port Lincoln. The pilot requested emergency services be placed on standby as the aircraft had a hydraulic problem and he was unable to extend the landing gear normally. After successfully carrying out a manual extension of the landing gear the aircraft was landed safely. A maintenance investigation revealed a cracked flared fitting in the hydraulic system, which allowed the system fluid contents to be lost. The fitting was changed and the aircraft returned to service. The fitting is the subject of a Defect Report to CASA.

The Departures North controller was controlling a Beechcraft Super Kingair B200C, radio callsign Alpha-Mike-Mike, and a British Aerospace BAe146 radio callsign Echo-Whiskey-Mike. Both aircraft had departed Sydney to the south-east. The crew of the Kingair were flying a radar departure, on a heading of 120 degrees, maintaining 5,000 ft. The crew of the BAe146 were flying a runway 16L COOKS ONE standard instrument departure (SID).

The Departures North controller confused the callsigns of the two aircraft and, although intending to turn the B200C, mistakenly instructed the crew of the BAe146 to turn left onto a heading of 350 degrees. The BAe146 was then cleared to leave 5,000 ft on climb to flight level 240. The combination of both instructions placed the BAe146 in the Approach South/Director controller's airspace and in potential conflict with a Boeing B737 on left downwind for runway 25 that had been assigned descent to 5,000 ft.

Both the Approach South controller and the Departures North controller recognised that the aircraft were in conflict as soon as the BAe146 started to turn onto the assigned heading and issued remedial instructions to both crews.

The required separation standard was either 1,000 ft vertically or 3 NM horizontally. Analysis of the radar data indicates that the B737 did not descend below 5,500 ft and that the BAe146 did not climb above 4,600 ft. The vertical difference of 900 ft occurred while the aircraft were less than 3NM apart and there was consequently an infringement of the separation standards.

The crew of the BAe146 sighted the B737 and were able to maintain visual separation.

The investigation revealed that the Departures North controller had worked six extra shifts on overtime or emergency duty in the previous 7 weeks, including an overtime shift the previous day. Fatigue was considered to be a contributory factor.

LOCAL SAFETY ACTION

Air Traffic Control Management at Sydney made two recommendations as a result of this incident:

"Recommendation 1. That strategies be put in place to limit the amount of overtime or extra duties worked by terminal control unit (TCU) staff. Should the present measures be withdrawn, other measures will be necessary".

"Recommendation 2. That the mode of operation, 16 Departures/25 Arrivals, be reviewed so as to permit two outbound radials to the north for different performance aircraft".

BASI SAFETY ACTION

As a result of this investigation and a number of similar occurrences, the Bureau of Air Safety Investigation conducted an investigation of systemic issues at the Sydney terminal control unit and issued report B98/90 on 18 August 1998. Nine recommendations were made in the report. The following two recommendations are considered relevant to this investigation.

R980159

The Bureau of Air Safety Investigation recommends that Airservices Australia reassess the human factor hazard analysis for both Stage One and Stage Two of the long-term operating plan (LTOP) safety cases so that the mitigating strategies applied to identified hazards adequately allow for the fundamental limitations of human performance. In reassessing this hazard analysis, BASI recommends that Airservices Australia seek the assistance of human performance expertise.

R980160

The Bureau of Air Safety Investigation recommends that Airservices Australia consider restructuring the current roster operating in the Sydney TCU to ensure that contemporary fatigue management research is translated into meaningful duty hour regulations. In any restructure of the roster, BASI recommends that Airservices Australia expand its absentee management program to include individuals who expose themselves to the risks of fatigue by participating in excessive amounts of overtime and/or emergency duty.

The aerodrome controller (ADC) at Perth tower had cleared the Boeing 737 to line up on runway 21. An Airservices Australia car was accompanying the airfield mower cutting grass at the runway's edge, approximately midway along the runway. The ADC was aware that the car was just within the flight strip but he was not aware of the existence of the mower. Only after he cleared the 737 to take off and it had begun rolling, did he become aware of the mower and its close proximity to the runway. He instructed the pilot of the 737 to cancel the take-off.

The surface movement controller (SMC), who had not heard the take-off clearance, became aware of impending confliction when the aircraft began rolling. He instructed the car to vacate the flight strip. The aircraft stopped approximately 600 m before the original position of the mower having rolled approximately 750 m. The mower was a small blue vehicle and was approximately 1500 m from the tower and would have been difficult to see from the tower. The ADC had taken over the position approximately 10 minutes prior to the incident. He reported that he could not recall being advised about the mower during the handover so the ADC was unaware of the mower's existence.

However, the "runway occupied" strip had been placed in the ADC's departure runway designator console but because the ADC did not post the aircraft's flight strip on the console before clearing the aircraft for take-off, he did not note that the mower's operation near runway. The manual of air traffic services (MATS) details a requirement that an aircraft not be issued with a take-off clearance until its flight strip has been placed under the "runway occupied" strip at the ADC console and the runway has been vacated. When the ADC issued the take-off clearance, he had assumed that the SMC had ensured that the runway was vacated although he had not coordinated with the SMC to ensure that such was the case.

The tower coordinator normally supervised the operations within the tower but he was pre-occupied at the time recording information for the automatic terminal information service (ATIS). He had, therefore, not noticed the incident developing until the aircraft had begun its take-off run. He reported that he then called to the ADC to stop the aircraft because there was a vehicle on the runway.

LOCAL SAFETY ACTION

Airservices Australia has issued a local instruction highlighting the necessity of full handover procedures and a requirement to address escort vehicles with their callsign and escorted company on all radio communications and during tower coordination.

When the pilot of VH-SWT requested start approval and clearance at 0535 EST, the callsign was not that which had been flight planned. Processing of the new callsign and the allocation of a transponder code, along with other arrivals and departures, delayed the departure of SWT for about 20 minutes. The aircraft was to depart from runway 01 at the taxiway A7 intersection.

At 0557, at B747 aircraft landed on runway 19. At this time, the high intensity runway edge lights, as well as the runway centreline lighting, were selected for runway 19. The B747 was still on the runway but south of the A7 intersection when SWT was cleared to line up. Because of this, the runway 19 high intensity edge lights were left on as were the runway 19 centreline lights. (The high intensity edge lighting and the centreline lighting cannot be selected for both runway 01 and runway 19 at the same time.) This meant that the only runway lighting illuminated for runway 01 was the white omnidirectional runway edge lighting. The green taxiway centreline lights were on.

These extended from taxiway A7 to the runway 01 centreline. When SWT was issued with a transponder code and cleared for an immediate departure, the aircraft was at the holding point at A7. The pilot read back the incorrect code and was again given the correct code. To enter the code into the transponder, he had to lean across the cockpit to the right side of the instrument panel. He did this as the aircraft entered the runway. When he looked forward again, he saw a line of white lights directly ahead and commenced the takeoff roll. Almost immediately, he heard a noise from the left side of the aircraft and rejected the take-off. 

The left propeller had struck one of the high intensity runway edge lights. The propeller was damaged and the light housing destroyed. It appears that when the pilot leaned across the cockpit to enter the transponder code, he veered left of the taxiway lights leading to the runway centreline and then assumed that the omnidirectional edge lighting depicted the runway centreline. As a result of this incident, Airservices Australia has written to the airport operator proposing that the lighting system be modified so that the centreline lights for runways 01 and 19 are omni-directional.

A letter supporting this proposal has been sent from BASI Brisbane Field Office to Brisbane Airport Corporation Limited. The operator is issuing a memo to all pilots advising them of the incident and the runway lighting arrangements which can apply when one runway is being used for arrivals and the other for departures.

The pilot of the Piper Seminole reported that he was involved in a near-miss with another aircraft while conducting a practice instrument approach to the Yarrowee navigation aid. As the Seminole was approaching Yarrowee, the pilot established communications with the pilot of a VFR Cessna 177RG conducting Airwork over the aid. After each pilot had advised the other of his intentions, the pilot of the Seminole understood that the Cessna was concluding its Airwork and departing the area for Ballarat. Subsequently, during the inbound turn of the instrument approach, the pilot of the Seminole reported seeing the Cessna very close to his aircraft and initiated a rapid descent to maintain separation.

The pilot of the Cessna later reported that he had the Seminole in sight at all times and did not believe that there was a breakdown in separation. He was unable to recall the details of the communications between the aircraft and could not explain why the pilot of the Seminole understood that the Cessna had departed the area.

In the absence of any independent corroboration, such as radar tapes, of either of the two conflicting versions of events, the following is a likely scenario. Based on his communication with the pilot of the Cessna, the pilot of the Seminole believed that his aircraft was the only aircraft in the area. When the Seminole pilot suddenly observed an aircraft close to his own, he may not have had sufficient time to assess the relative flightpaths and thus believed that a collision was imminent. The investigation was unable to determine if the Cessna pilot informed the pilot of the Seminole that he was still in the area and that he was maintaining visual separation.

SAFETY ACTION

The Bureau of Air Safety Investigation is currently investigating a perceived safety deficiency that has been identified as a result of this and similar occurrences. This deficiency involves the lack of a published requirement for aircraft conducting airwork over a navigation aid not associated with an airport to alert other aircraft prior to arriving overhead the aid. This requirement would provide the opportunity for aircraft to arrange mutual separation.

Any recommendation issued as a result of this investigation will be published in the Bureau's Quarterly Safety Deficiency Report.

The pilot of an amphibious Cessna 206 had been chartered to fly two passengers from an aircraft landing area at Warnervale to Berowa Waters on the Hawkesbury River.

A gusty 20 kt westerly wind was blowing in the Warnervale area at the time of aircraft departure. The pilot recalls being concerned about making an approach into Berowa Waters and encountered turbulent and uncomfortable weather conditions enroute.

After making a normal approach to the landing area, the pilot closed the throttle and flared the aircraft. As the floats touched the water, the aircraft tipped forward and the nose of the aircraft dived under water, which caused the windscreen to shatter. Water flooded the cabin and the aircraft came to rest inverted. The pilot and the two passengers were not seriously injured and evacuated the submerged cabin through the door on the left side of the aircraft.

Immediately following this occurrence, the pilot observed that the float mounted landing gear was in the extended position and not correctly positioned for a water landing. He cannot recall any actions specific to the landing gear following the departure from Warnervale or on arrival at Berowa Waters.

Following recovery of the aircraft to dry land, the landing gear selector was observed to be in the neutral position.

The pilot of an arriving aircraft requested that emergency services be placed on standby, as his aircraft was experiencing engine surging in the right engine and he did not expect to make a normal approach. A short time later the aircraft made an uneventful landing and taxied to the general aviation terminal accompanied by a fire tender. An investigation was subsequently carried out by a maintenance organisation with no fault found. This included draining and testing 20 litres of fuel from both main tanks. No contamination problem that may have attributed to the engine surging could be identified. After engine ground runs to verify operations were within limits, the aircraft was returned to service.

The pilot advised Flight Service (FS) that the engine had failed, and he was attempting a landing at the Mittagong airstrip. The aircraft subsequently landed approximately 2 km short of the airstrip damaging the left-wing tip and landing gear during the rollout. The pilot advised FS of the situation and that there were nil injuries. The initial maintenance investigation discovered that the crankshaft accessory drive gear positioning dowel had sheared. This in turn had ceased the drive to all the engine accessories and the camshaft, resulting in the engine stopping. The initial reason for the failure of the dowel could not be positively determined. 

Subsequent to the initial investigation, a detailed failure analysis of the failed engine components was carried out. This examination revealed that a significant factor in the failure of the crankshaft gear/crankshaft attachment had been a manufacturing irregularity on the bearing surface of the head of the attaching bolt. The manufacturing irregularity resulted in a reduced clamping force, between the gear and the crankshaft, being established during assembly. The loss of the clamping force had allowed relative movement between the gear and the crankshaft mounted gear positioning dowel. This eventually led to the fatigue failure of the dowel and the loss of integrity of the accessory gear drive assembly.

The pilot of FDP had been instructed to taxy to the holding point at taxiway A2 for departure. The Surface Movement Controller then diverted his attention to other traffic. The Aerodrome Controller then noticed that FDP was holding at the intersection of runway 15 and taxiway A3 , partially inside the holding point.

The pilot advised that the aircraft was slightly inside the holding point and asked for approval to conduct engine checks in that position. As there was no immediate traffic, the aircraft was cleared onto the runway. The pilot reported that he did not see the holding point marking until he had passed over it. He added that the marking did not extend across the full width of the taxiway, and felt that this contributed to the incident. In addition, he had not operated into Cairns for more than 2 years, so he was not completely familiar with the aerodrome layout.

The comments by the pilot on the holding point marking were discussed with the local Airservices manager and the airport owner. Both these agencies indicated that there had been other instances of pilot confusion concerning taxiway markings in the same area. It was agreed that Airservices would arrange for a 'Caution' note to be inserted in the En-route Supplement advising pilots to exercise caution when approaching the taxiway A3 holding point. The airport owner was completing arrangements to repaint the holding point marking to extend the full width of the taxiway, and to repaint the holding point and frequency information on the associated gable marker.

The aircraft was being prepared for a freight flight with newspapers included as part of a standard load for this service. Normally the newspaper publisher informed the operator of the weight of the consignment and the newspapers would arrive at the airport in sufficient time to ensure an on time departure. However, on this occasion, the consignment was delayed. The duty manager decided to delay the flight's departure to await the arrival of the newspapers.

The aircraft's upper deck and Compartment 1 of the lower deck had been loaded, and the manager intended to load the newspapers in the rear compartment of the lower deck in which 670 kg of weight allowance was available. The duty manager had the newspapers weighed and found them to be heavier than normal at a weight of 1,070 kg. He reported that he had informed the captain that the consignment was 400 kg overweight but the captain later stated that he had not been told of the discrepancy. The newspapers were loaded and the aircraft departed 20 minutes later than its scheduled departure time. The loading crew at the destination opened Compartment 1 and noted the Universal Loading Device (ULD) tag as showing the weight of an item of cargo as 87 kg.

The crew did not believe this figure and checked the weight at 277 kg. The loading crew then opened the rear compartment and noted a ULD tag showing a cargo weight of 607 kg. They again checked the weight and found 1,172 kg of newspapers and 78 kg of other freight. The net effect of these discrepancies was that the aircraft was heavier than its maximum zero fuel weight limit and that the centre of gravity was aft of its computed position, although within limits. The flight crew reported that the flight was normal and free from any noticeable abnormalities in aircraft performance or handling.

Since the occurrence, the operator has replaced the ULD tags with new "user friendly" tags designed to reduce the probability of error. The reason the crew were unaware of the excess load could not be determined.