Abstract

At about 1328 on Saturday 5 February 2011, scheduled XPT (Express Passenger Train) ST24, travelling from Melbourne to Sydney, passed signal 09-6 at Henty while it was displaying a Stop (red) indication, an event commonly referred to as a Signal Passed at Danger (SPAD). The train stopped about 95 m past signal 09-6 with the front of the leading power car on the Yankee Road level crossing. The investigation concluded that notwithstanding a reported issue with the brakes on the leading power car, the driver of train ST24 did not apply sufficient braking effort to enable train ST24 to be stopped before passing the Up-home signal (09-6) at Henty.

At 1305 Eastern Daylight-saving Time on 1 February 2011, a breakdown of separation occurred 22 km south of Williamtown (Newcastle Airport), New South Wales between a Boeing B737-7Q8 (737), registered VH-VBK, and an Israel Aircraft Industries Ltd Westwind 1124 (WW24) aircraft, registered VH-AJG. Both aircraft were in communication with and under the jurisdiction of Department of Defence (DoD) air traffic controllers based at Williamtown.

Separation between the aircraft reduced to 0.7 NM (1.3 km) on radar and 400 ft vertically when the required separation standard was 3 NM (5.6 km) or 1,000 ft. The vertical separation achieved was as a result of the 737 flight crew responding in accordance with a resolution advisory provided by their aircraft's traffic alert and collision avoidance system.

The investigation identified a series of errors by the Williamtown Approach controllers involving separation assurance, coordination and communication, and compromised separation recovery.

The investigation also identified three safety issues. The DoD advised that they reviewed and amended Williamtown procedures, introduced compromised separation recovery techniques training and trialled use of the conflict alerting function in the Australian Defence Air Traffic System at Williamtown.

On 31 January 2011, an Airbus A320-232 aircraft, registered VH-VQN (VQN), was taxiing for runway 29 at Darwin Airport, Northern Territory on a scheduled passenger service to Sydney, New South Wales.

The crew required a clearance to cross runway 11/29 in order to access the main taxiway for runway 29. On reaching the runway holding point, the crew received a clearance from air traffic control to cross the runway.  Prior to crossing, the crew checked the runway and approach paths for traffic. The pilot in command (PIC) stated that they were clear to the left, but the copilot noted that there was an aircraft lined up and stopped on runway 11. Soon after, the copilot observed the aircraft commence its take-off roll. He advised the PIC, who immediately stopped the aircraft. VQN had taxied past the holding point, but was short of the runway, resulting in a runway incursion.

Shortly after, they observed a Cessna 404 aircraft, registered VH-UOP (UOP), on a scheduled passenger service from Darwin to Snake Bay, Northern Territory take off on runway 11. A breakdown of runway separation occurred.

Air traffic control had provided the instruction for VQN to cross the runway based on the expectation that UOP would have commenced the take-off soon after receiving a take-off clearance.

Runway incursions are recognised as an ongoing safety concern for the aviation industry and have been cited in numerous accidents world-wide. This incident emphasises the need for controllers to remain vigilant in monitoring and scanning the runway and highlights the significance of pilots conducting a thorough visual inspection of the runway and approach paths prior to entering or crossing any runway, even if a clearance from air traffic control has been provided.

After a number of dual circuits, the pilot was authorized to carry out solo circuits with touch and go landings. After the first touchdown the pilot applied full power then selected the flap to 10 degrees. The aircraft entered a rapid turn to the left, and the pilot abandoned the take-off. The aircraft slid sideways off the strip and the nosewheel was broken off. The pilot was carrying out her first solo period of touch and go landings. After applying full power she noticed that the aircraft was accelerating more quickly than when she had been under dual instruction. The pilot had previously required forward pressure on the control column while retrimming the aircraft. On this occasion she had not had time to retrim and the investigation revealed that the aircraft had been "wheelbarrowing" on the nosewheel when directional control was lost.

The pilot held in the circuit area at his destination for about 10 minutes before carrying out a normal landing. He recalls checking that the landing gear indicated down and locked before landing. However, when the nosewheel was lowered onto the runway, the noseleg collapsed. The aircraft skidded on its nose for about 150 metres before coming to rest on the runway. The nosegear indicator still showed a green light after the aircraft came to rest. The cause of the nosegear collapse could not be determined. The false safe indication of the nosegear was possibly caused by a foreign object under the downlock microswitch.

The pilot advised that he was taxying towards the take-off threshold of the ALA, using the grassed area alongside the gravel strip. He noticed an anthill about 30 centimetres high in front of the aircraft, but while turning to avoid the obstruction the left mainwheel struck the anthill. The gear leg broke at its attachment point to the wing, resulting in substantial damage to the wing and the left flap.

A spray run was being flown along the boundary of a paddock. One tree infringed the run and the trainee elected to apply rudder to direct the aircraft past the tree. Incorrect rudder was applied and the instructor took over but the left wing struck the tree. The instructor was able to maintain control although one metre of wing and the aileron had been torn off. He landed the aircraft in the adjoining paddock without further damage.

The pilot and passengers were on the return leg of a flight begun earlier that day. The weather forecast the pilot had obtained included reference to a frontal passage, which would be followed by low cloud, rain and thunderstorm activity. The flight evidently proceeded normally for about two hours, by which time the aircraft was to the south-west of Tamworth. At this point, the pilot reported that he was returning to Tamworth, however, this transmission finished abruptly and nothing further was heard from the aircraft. The wreckage was subsequently located two days later, close to the planned track. The aircraft had struck a ridge 2200 feet above mean sea level, while banked steeply to the right and descending. No defect was subsequently found with the aircraft which might have contributed to the development of the occurrence. At the time of the accident weather conditions in the area were poor, with layers of thick cloud and an embedded cumulo nimbus or large cumulus present. The pilot did not hold an instrument rating, and had only limited experience on the type and on relatively high performance aircraft in general. It was probable that the aircraft was cruising between cloud layers when the pilot noticed deteriorating conditions ahead. While attempting to turn away from these conditions, the pilot probably inadvertently entered the cloud. Control of the aircraft was then lost when the pilot was confronted with a lack of visual reference in turbulent conditions.

The aircraft had been parked in a hangar and not flown for six months until the day before the accident. After landing on that occasion the pilot noticed that the airspeed indication was slow to return to read zero. The next day the pilot believed the airspeed took longer than usual to reach the normal cruise indication. When on final, with an indicated airspeed of 80 kt the stall warning light illuminated, the aircraft stalled and struck the ground. Prior to the second flight the pilot had attempted to clear the pitot/static system by blowing into the pitot tube. Inspection of the static system found evidence of a blockage by an insect nest. The blockage was in such a position that it would not have been visible during a preflight inspection.

The pilot had hired the aircraft in order to maintain currency on the type. After an uneventful flight in the training area he returned to the circuit and carried out a normal approach. However, shortly after touchdown the aircraft swerved to the left and the pilot was unable to regain directional control. The aircraft ran off the side of the runway and the nosegear collapsed. It was discovered that the elevator trim had been set almost fully nose down, and the rudder trim was set almost fully nose left at the time of the accident. The nosewheel had contacted the runway at about the same time as the mainwheels, and it was likely that the subsequent loss of control was the result of the aircraft "wheel-barrowing" on the nosewheel. The pilot, who had only limited experience on the type, had believed that the aircraft had been correctly trimmed prior to touchdown.