The Aviation Short Investigation Bulletin covers a range of the ATSB’s short investigations and highlights valuable safety lessons for pilots, operators and safety managers.
Released periodically, the Bulletin provides a summary of the less-complex factual investigation reports conducted by the ATSB. The results, based on information supplied by organisations or individuals involved in the occurrence, detail the facts behind the event, as well as any safety actions undertaken. The Bulletin also highlights important Safety Messages for the broader aviation community, drawing on earlier ATSB investigations and research.
The Aviation Short Investigation Bulletin, Issue19 features nine safety investigations:
Pilot pressure and the layout of a non-towered aerodrome contributed to an airspace incident between a Beech 1900C and an Aerospatiale AS350 B2 helicopter, according to an ATSB investigation.
The incident occurred on 6 September 2012 at Newman Aerodrome in Western Australia. The Beech had made all required radio broadcasts and was on its take-off roll when the pilot saw the Aerospatiale helicopter unexpectedly enter the runway strip and take off parallel to the runway. The pilot of the Beech believed the paths of the two aircraft could cross if they both became airborne and, although his airplane was by this time moving at about 222 km/hr, he aborted the take-off. As the aircraft slowed, he saw the helicopter turn right and cross the runway about 200 m in front of the Beech and about 200 ft above ground level.
The pilot of the helicopter only became aware of the Beech when he heard the Beech’s co-pilot broadcasted that he was aborting the take-off. The Aerospatiale pilot made all required radio broadcasts but heard only one garbled transmission which may have been the Beech’s ‘rolling’ call.
New hangars had recently been built at Newman, which obscured the view from the GA apron to the threshold of the runway.
The pilot of the helicopter later explained that he had received word that a person at a survey site had been injured and required immediate evacuation. Feeling pressure to get to the injured person, he had turned right across the runway when the normal procedures required him to turn left.
At and around non-towered aerodromes, pilots are responsible for making themselves aware of nearby aircraft and maintaining separation. However, new hangars had recently been built at Newman, which obscured the view from the GA apron to the threshold of the runway. The hangars were also thought to be responsible for blocking radio transmissions between aircraft on the GA apron and those on the threshold of runway.
In response to this incident, the airfield operator is seeking to have a warning included in the aviation information publication for Newman. This warning describes the possible shielding effects from the aircraft hangars and requires adherence to specific procedures for helicopter arrivals and departures.
A study by the National Aeronautics and Space Administration (NASA) has found that perceived or actual pressure can contribute significantly to degradation in human performance and behaviour. The study recommended that pilots be particularly cautious if distraction or time pressure are encountered during the pre-flight or taxi phases of a flight.
The ATSB’s investigation into the engine failure of a Cirrus SR22 aircraft shows why it’s vital to always follow the aircraft manufacturer’s operating guidance.
During a flight from Emerald, Queensland to Dubbo, NSW on 21 November 2012, the engine indications on the Cirrus SR22 were showing a gradual loss of oil pressure. Despite the pilot’s operating handbook advising the pilot to promptly land the aircraft to find the cause of the oil pressure loss, he decided to monitor the situation after contacting the maintenance organisation for advice.
The oil pressure continued to drop and eventually the engine failed when the aircraft was 11 minutes from Dubbo, near Gilgandra. The pilot was not able to land at the Gilgandra airport and elected to deploy the ballistic parachute system fitted to the aircraft. The aircraft landed upright in a paddock and fortunately, the pilot and the passenger escaped with minor injuries.
The pilot commented that the oil pressure indication dropped very gradually, giving a false sense of security. Three or four weeks previously, the aircraft’s engine temperature probe had failed. As the engine cylinder head temperature and oil temperature indications remained in the normal range, the pilot thought that the low oil pressure may have indicated another faulty probe.
The aircraft had flown only around 4 hours following a 100 hour maintenance check. When the pilot conducted the pre-flight check for the accident flight, he noted that the oil level was below 5 quarts and 1 L of oil was added to the engine. The pilot’s operating handbook notes that the engine should not be operated with less than 6 quarts of oil and 7 quarts is recommended for extended flights.
The ATSB is urging port managers and operators to consider all the risks associated with operations within their ports following the foundering of a ship at Christmas Island in 2012.
On the morning of 8 January 2012, one of the permanent mooring lines holding the general cargo ship Tycoon in position at Flying Fish Cove, Christmas Island, came free from its anchor. As a result, the ship moved forward and closer to the nearby terminal rock face, eventually hitting the rock face as the weather and sea conditions deteriorated.
Despite attempts to move it away, Tycoon continued to pound against the rock face. Eventually, the ship’s engine room began to flood through a tear in the hull. Shortly afterwards, the crew safely abandoned the ship.
The next day, Tycoon suffered a catastrophic failure of its hull and the contents of the ship’s number two cargo hold, about 260 tonnes of bagged phosphate, were exposed to the sea. The ship continued to be pounded by the sea and swell and, over the following months, it broke up. The wreck was eventually removed by salvors on 26 July 2012.
The ATSB investigation found that the shackle connecting the port’s mooring line to its anchor chain had failed. As well, Tycoon’s master did not advise shore authorities of his concern about the deteriorating conditions or that the mooring line had come free. He also did not make proper use of the ship’s main engine or mooring lines in an attempt to keep the ship in position after the mooring line came free.
...the ship’s engine room began to flood through a tear in the hull.
In addition, it was found that there had been no risk assessment undertaken by successive port managers with respect to the use of the inner moorings and that there was little guidance provided to the masters of ships intending to moor in Flying Fish Cove. The managers of the port had not implemented an effective inspection and maintenance program and therefore were not aware of the deteriorated condition of the mooring line shackle.
As a result of the accident, the port operator has commenced replacing and upgrading the mooring equipment. They are also developing a Port Handbook which will be provided to the master of each ship and are facilitating safety training workshops that will be a forum through which the risks posed to the port and its operations can be assessed.
The ATSB investigation report advises port authorities to have procedures and contingency plans in place to deal with foreseeable emergencies. In addition, it is vital that there be effective maintenance and inspection regimes to ensure the good order of equipment and facilities.
An unmanned airship was on a test flight in Keysborough, Victoria when its remote-pilot lost control before the aircraft flew into the controlled airspace of Moorabbin Airport.
The incident occurred on 28 October 2012, when a team comprising a pilot, observer and software engineer were conducting a test flight of the airship. The aircraft, weighing less than 8 kg, consisted of a 10 m long balloon with a gondola suspended below and was remotely controlled by the pilot using a portable radio-controlled transmitter. The crew planned to fly the airship below 200 ft and within 200 m of their location to ensure it remained clear of the Moorabbin Class D control area.
Shortly after take-off, the crew noticed that the airship’s nose was tilting up due to its rearward centre of gravity. The pilot corrected the tilt but a minute later, when the aircraft was at about 130 ft off the ground, he realised that he could not turn it to the left, although it still could turn right.
The pilot attempted unsuccessfully to contact the Moorabbin control tower by radio to advise them of the situation.
The pilot tried to land the airship, but the rearward centre of gravity resulted in it climbing. The airship’s elevator (or height) controls were also not responding. As it climbed through 200 ft above the ground, the pilot realised he had lost total control of the airship, He reduced the engine power, but the airship continued to climb and fly in a north-westerly direction toward the Moorabbin Airport.
The pilot attempted unsuccessfully to contact the Moorabbin control tower by radio to advise them of the situation. He and the software engineer then got in a car with the portable radio-controlled transmitter to follow the airship by road. The observer remained at Keysborough and contacted the Moorabbin control tower and emergency services via telephone.
The air traffic controllers at Moorabbin spotted the airship around 4 km to the south-east at about 1,000 ft above the ground. This was also confirmed by the pilot of an aircraft flying in the Moorabbin circuit.
Thirty minutes later, the airship landed on the roof of a commercial building, sustaining minor damage.
Data provided to the ATSB by the airship operator indicated that the airship reached a height of 1,930 ft and, at its closest, was 5 km from Moorabbin Airport.
The airship operators have advised the ATSB that they will take a number of measures to prevent similar incidents. This includes developing a pre-flight checklist and change management process to consider risks when changes are made to hardware or processes. They will also be locating a suitable site for flight testing away from populated areas.
There are regulations that set out the requirements for the operation of unmanned aircraft (including airships); however, the size of the airship’s balloon meant that it did not have to be registered, and it was not subject to airworthiness and flight crew qualification requirements.
The Civil Aviation Safety Authority is currently working to provide more comprehensive guidance on the regulatory requirements and approval processes for the commercial operation of unmanned aircraft systems in Australia. The guidance will consider the long-term integration of unmanned aircraft systems into normal aviation operations in all classes of airspace.
Aircraft passengers are being reminded to fasten their seatbelts at all times while seated after a Virgin Boeing 737 encountered wake turbulence.
The incident occurred on 13 September 2012 when the aircraft, carrying 132 passengers, was en route from Bali to Brisbane. While in cruise, the 737’s crew spotted an aircraft above, approaching from the opposite direction. The aircraft passed about 0.9 Nautical Miles to the left and 1,400 ft above.
About one minute later, the 737 experienced cobblestone-like turbulence. It then rolled slightly to the right and then suddenly to the left to an angle of about 40°. The crew managed to arrest the roll and straighten the aircraft. The incident occurred as a result of wake turbulence from an Airbus A380 aircraft.
A wake turbulence encounter can be a surprising experience for both the crew and passengers...
Fortunately all the aircraft’s passengers were seated at the time of the incident and there were no reported injuries. The flight continued without further incident.
Pilots receive six-monthly jet upset simulator training to prepare them for situations when an aircraft experiences pitch or roll conditions greater than normal. Both the captain and the first officer of the 737 had received their training within the past two months—the captain’s training took place within the week before the incident. They both reported that the training was invaluable, with the first officer remarking that his response to the wake turbulence had been instinctive and that the incident was similar to that experienced in the simulator.
A wake turbulence encounter can be a surprising experience for both the crew and passengers and usually results in induced rolling or pitch moments. A safety bulletin published by the ATSB, Staying Safe against In-flight Turbulence, noted that almost all turbulence injuries involve people who are not properly seated and do not have their seat belt fastened. This incident is a timely reminder to have your seat belt fastened, even when the seat belt sign is turned off, so that injuries during a turbulence encounter can be minimised.
A fatal accident near Hallston, Victoria has illustrated the dangers of partial power loss after take-off in single-engine aircraft — a problem that the ATSB has been emphasising to the aviation community.
The accident occurred on 1 May 2012, when the pilot of a Piper PA25 was conducting agricultural operations from a local airstrip near Hallston. Shortly after take-off, the aircraft crashed near the base of a gully and was destroyed by fire. The pilot, the only person on board, died in the accident.
...partial power loss is actually a more complex situation than a complete failure, and can be much harder to manage.
The damage sustained during the impact and ensuing fire prevented the ATSB investigation from identifying specific reasons for the aircraft’s loss of power. ATSB General Manager Strategic Capability, Mr Julian Walsh, says that partial power loss is actually a more complex situation than a complete failure, and can be much harder to manage.
"The pilot is in a situation where the engine is still providing some power, but it may be unreliable, and the available power level might be difficult to assess," Mr Walsh says.
"As a result, pilots are uncertain about their aircraft's capabilities, and what their options are— a situation that can turn into disaster very easily."
A number of resources are available to help pilots prepare themselves for a partial power loss. One of the booklets in the ATSB’s Avoidable Accidents series, Managing partial power loss after take-off in a single-engine aircraft, provides information and strategies for dealing with such a situation if it arises.
The swift actions of a jet’s flight crew following a shattered windshield in flight has shown how good flight planning can make all the difference.
On 15 January 2013, a Cessna Citation 750 was carrying two flight crew and five passengers from Faleolo, Samoa to Sydney, Australia. The aircraft levelled off at 45,000 feet, when its system reported a problem with the windshield heating system.
The windshields were laminated glass with outer, middle and inner panes of glass. The pilot found that the windshield was warm to the touch, but the only advice the checklist gave was to leave icing conditions as soon as practical.
The cabin was prepared for a possible ditching, with the passengers directed by the flight crew to don their life vests and review the safety briefing card.
Two minutes later, the outer ply of the windshield shattered with a loud bang. Cracks spread across the entire surface of the left pane.
The flight crew switched off both the left and right windshield heat switches, and completed the emergency depressurisation checklist. They donned their oxygen masks and deployed the passenger oxygen masks.
The pilots commenced an immediate descent along with a turn towards Nadi International Airport, Fiji, which was one of the planned alternate airports. The pilot declared a mayday which was acknowledged by Nadi radio. Once the descent was established, a flight crew member ensured the passengers were on oxygen and briefed them on the situation. The cabin was prepared for a possible ditching, with the passengers directed by the flight crew to don their life vests and review the safety briefing card.
During the descent, the windshield cracking did not progress further. The cabin did not depressurise, and once they were at 14,000 feet and with the cabin altitude stabilised, the passengers were directed to remove their oxygen masks. The flight continued to Nadi without further incident. There were no injuries to passengers or crew.
The ATSB investigation found that the windshield had likely been affected by moisture seeping into the heating equipment, degrading the electrical connections. The manufacturer has taken measures to the address the issue.
While the failure of the windshield did not result in a depressurisation, the precautions taken by the flight crew to descend to a lower altitude and diversion to the alternate airport highlighted the importance of good flight planning.
A runway accident involving a Cessna T210 reinforces the need for pilots to take extreme care when using unsealed runways.
The accident happened on 30 December 2012 when the Cessna, with a pilot and five passengers on board, was taking off from Cape Leveque airfield in WA. Cape Leveque is an unlicensed airfield managed by a tourist operator. It comprises a 972 m long and 40 m wide strip of compacted soil. There had been rain on the strip during the previous days and an early shower on the day of the accident. The airfield is monitored for serviceability and was deemed suitable on the day of the flight; however, after the accident an inspection of the airstrip revealed that there had been a substantial washout on the edge of the strip. The managers closed the airstrip for grading and repair.
Early in the take-off, the Cessna veered to the left. The pilot tried to straighten the aircraft with rudder and continue with the take-off, but ended up about a metre left of the runway centre line. About halfway down the runway the aircraft veered sharply to the left again. The pilot again tried to correct the veer, but the aircraft did not respond. He slowed the aircraft before the left wing clipped trees along the edge of the airstrip, making the aircraft swing almost 90 degrees before the right wing struck the ground. The nose-wheel collapsed in the soft sand on the edge of the airstrip resulting in the propeller striking the ground. One of the passengers sustained minor injuries and the aircraft was substantially damaged.
After the accident, the pilot of the second aircraft inspected the airstrip and reported substantial washout on the edge of the strip inside the cone markers.
As a result of this accident, the aircraft operator has reinforced the need for their pilots to:
keep the nosewheel on the centreline of the runway at all times
use the right rudder during take-off
where possible avoid loose dirt and rough areas on the side of the runway
close the throttle immediately, if the take-off needs to be rejected
A go-around is always a viable option when pilots experience any problems during landing. The ATSB emphasised this point after a pilot, partially blinded by glare, opted to continue his landing, and as a result his aircraft departed the runway and travelled through two fences before coming to a stop.
The accident occurred on 23 August 2012, at Urapunga in the Northern Territory. The aircraft was a Cessna 210N, carrying the pilot and two passengers on a charter flight. While the aircraft was descending, the sun created a glare on the windscreen that greatly restricted visibility.
The pilot was wearing non-polarised sunglasses, which helped only slightly. The aircraft’s sun visors were not effective because the sun was low on the horizon. Nevertheless, the pilot thought he could identify the runway through the glare and saw what he thought was the runway centreline, so he continued his approach.
The pilot reported intermittent sun glare during descent...
As the aircraft floated down above the runway, the pilot was unsure of the amount of runway that had been used. The aircraft touched down and the pilot applied heavy breaking in short bursts. The aircraft slowed a little on the runway’s gravel surface before leaving the end of the runway, and travelling through two fences.
The aircraft came to rest on the right side of the fuselage, right wing and right horizontal stabiliser. The pilot received minor injuries from barbed wire while he was evacuating from the aircraft.
There are several studies by the US Federal Aviation Administration and the ATSB on overruns and the value of being prepared to go around.
