On 27 March 2013, a Raytheon B200, registered VH-ZCO, was being operated on an aero-medical flight from Darwin to Port Keats, Northern Territory. On board the aircraft were the pilot and two flight nurses.

In preparation for landing at Port Keats the pilot selected the gear down. The left and right main landing gear down indication lights did not illuminate, while the nose landing gear down indication light (green) illuminated. The pilot elected to return to Darwin and advised air traffic control.

The pilot reported that on landing, the right main landing gear wheel touched down first and when the left landing gear wheel touched down the pilot felt the left side of the aircraft start to sink. The pilot shut down the left engine and feathered the left propeller, then shut down the right engine and feathered the right propeller. The left wing then contacted the runway, and the aircraft skidded to a stop, at about 1551. The pilot and flight nurses evacuated the aircraft via the overwing exit. The aircraft sustained minor damage, while the pilot and flight nurses were not injured.

The operator determined that during the last overhaul of the left main landing gear, a washer was not installed, which resulted in the landing gear contacting the aircraft structure preventing the landing gear from locking in the down and locked position.

The Civil Aviation Safety Authority (CASA) conducted an investigation into the accident and found that there was no conclusive way to determine when the washer installation error occurred. CASA also established that this error was an isolated event.

The manufacturer was informed of the accident and determined that the missing washer would not have led to the failure of the landing gear to lock down. They believed that it was more likely that the drag brace was not installed or rigged correctly when installed on ZCO or that another landing gear assembly or maintenance error occurred, causing the circuit breaker to trip, resulting in the accident.

As a result of this occurrence, the aircraft operator has advised the ATSB that they are taking the following safety actions:

• A medical bag that was located near the overwing emergency exit was relocated.
• All B200 aircraft were inspected. The main landing gear on one aircraft was found not to be correctly assembled and this was rectified before further flight.
• A safety bulletin was issued to all staff to inform them of the accident.
• The training and checking department were to review the part within the proficiency check about this type of landing and ensure it is reiterated at the next base check.

Aviation Short investigation Bulletin Issue 22

In March 2013, the Australian Transport Safety Bureau (ATSB) received a request from the Civil Aviation Safety Authority (CASA) to assist with the non-destructive testing (NDT) and metallurgical examination of a wing spar bolt from a Beechcraft Model 35 (Bonanza) aircraft. The bolt had been removed for inspection as part of compliance activities with airworthiness directive AD/BEECH 35/67 and was reported as showing crack indications during preliminary NDT.

The ATSB was requested to examine the bolt with a view to confirming (or otherwise) the suspected cracking, and to provide commentary as to the likely contributing factors should the cracking be confirmed. To facilitate the work and provide for the issuing of a public report on conclusion of activities, the ATSB initiated an External Investigation under the provisions of the Transport Safety Investigation Act 2003.

Subsequently, the ATSB's non-destructive inspection of the bolt using both Magnetic Particle (MPI) and Fluorescent Dye Penetrant (DPI) techniques failed to reveal any indications of the reported cracking. To verify the NDT findings, the ATSB offered to conduct destructive metallurgical sectioning and metallographic examination, and in preparation for this, the wing spar bolt was returned to CASA and subsequently to the owner for re-examination to confirm the original findings.

In September 2013, following no further requests or confirmation of follow-up work, the ATSB discontinued the investigation in accordance with the provisions of section 21 (2) of the Transport Safety Investigation Act 2003.

On the evening of 22 February 2013, the crew of a Regional Express Saab 340B aircraft, registered VH-ZRL, were conducting a scheduled passenger service from Sydney to Taree, New South Wales.

During the approach to Taree, the crew monitored the weather conditions, with the crosswind initially observed as 50 kt when at about 6,000 ft, although it decreased as the aircraft descended.

At about 700 800 ft above ground level (AGL), the crew became visual with the runway. The crew assessed the approach and determined that it was suitable for landing. At that time, the crew reported that the wind was fluctuating and light rain was experienced.

At about 1904, the aircraft touched down. Immediately after, the crew reported that the aircraft was subjected to a wind gust, which caused the left wing to lift slightly and the aircraft to weathercock to the left, into wind. Reverse thrust had been selected after touchdown.

The aircraft veered left toward the runway edge and the captain assumed control of the aircraft. He applied right rudder, but the aircraft did not respond. As the aircraft’s airspeed decreased, the captain also applied right brake, with no effect. He then simultaneously commenced nose wheel steering using the tiller. As the captain believed that the nose wheel steering was ineffective, he elected to apply asymmetric thrust by reducing the amount of reverse thrust on the left engine and increasing reverse thrust on the right engine. The aircraft commenced moving to the right. The aircraft slowed and was taxied to the parking area.

After shutdown, using a torch, the FO then conducted a post flight inspection, with nil damage found.

The next day, the aircraft returned to Sydney, at which time maintenance personnel conducted an inspection of the aircraft and observed damage to the left propeller blades. All four blades had sustained stone damage predominantly on the back (reverse) of the blades.

Weather can behave in an unpredictable manner, particularly when unfavourable conditions exist. While this incident highlights the adverse effects weather can have on aircraft operations, it also emphasises the impact of complacency and interruptions/distractions.

Aviation Short Investigations Bulletin - Issue 31

On 22 March 2013, circuits were being conducted to both runway 31 left (31L) and 31 right (31R) at Moorabbin Airport, Victoria. The aircraft in the two circuits were operating on different frequencies and being controlled by different air traffic controllers under the visual flight rules (VFR).

At about 1625 Eastern Daylight-saving Time, a Cessna 172S aircraft, registered VH‑EWX (EWX), entered the Moorabbin control zone from the south-east and was instructed to track for base as number 1 in the landing sequence for runway 31R. Another aircraft, a Piper PA-44 (Warrior) aircraft, had been instructed to follow EWX as number 2 and a Piper PA‑28 aircraft, registered VH‑TXH (TXH), was number 3. A number of aircraft were operating to the west of Moorabbin in the circuit for runway 31L.

As EWX approached base, at about 1626, the pilot became aware of TXH in his 2 o’clock position, tracking contrary to the runway 31R circuit pattern. TXH was observed to pass under the nose of EWX, about 100 to 150 m in front and about 50 ft below. To avoid the other aircraft and to keep it in sight, the pilot of EWX turned to track behind and subsequently follow TXH. As the pilot executed this manoeuvre, Moorabbin Tower broadcast a safety alert.

TXH crossed the runway centreline for both runway 31R and 31L before joining final for runway 31R from the west. Both aircraft subsequently landed without further incident.

While pilots conduct a pre-flight inspection of their aircraft to determine airworthiness, this incident highlights the importance of pilots also assessing their own status. Personal minimums should be considered prior to flight, as well as the impact of stressors such as being unfamiliar with operations from a particular runway or the need to change aircraft due to an unserviceability.

Aviation Short investigation Bulletin Issue 22

The pilot commenced the landing flare at about 10 ft above the runway, during which time a bird struck the left wing. The aircraft yawed slightly left and the left wing dropped; the pilot applied opposite aileron to maintain wings level. The aircraft then drifted to the right of the runway into an adjacent paddock and the left wing struck a bull. The aircraft landed in the paddock. The aircraft sustained substantial damage from the bull strike and one passenger received minor injuries. The bull was put down as a result of the injuries sustained from the strike.

While the risk of wildlife strikes represents an ongoing challenge, and will always be present, this accident highlights the need to be aware of the hazards that may potentially exist within the vicinity of the runway and the benefits of overflying to alarm wildlife.

Aviation Short Investigation Bulletin - Issue 19

Response to Inquest Findings

The Coroner’s Court of Queensland, without holding an inquest, recently made findings into a 2013 fatal accident involving a Cessna T210N aircraft near Roma Airport.

The ATSB summary explains that on 25 March 2013, the pilot of a Cessna T210N aircraft and a passenger took off from Roma airport to the north about 30 minutes before dawn. The aircraft crashed descending in a left turn about 2 km north-west of the airport. There was no indication of any mechanical defects in the aircraft, however the pilot was not qualified to fly at night.

The Coroner adopted the Sequence of Events as set out in the Australian Transport Safety Bureau final report in relation to how the accident occurred and incorporated into his findings those of the ATSB regarding the likelihood of pilot spatial disorientation.

The Coroner stated:

Unfortunately for reasons that are currently unknown [the pilot] decided to take-off in darkness only 30 minutes from first light. The ATSB considers he suffered from the well-known phenomenon of spatial disorientation and the plane crashed into the ground causing his death and that of his passenger.

Safety message

This accident reinforces the need for day visual flight rules pilots to consider the minimum visual conditions for flight, including the relevant weather information and usable daylight. In this case, if the pilot had delayed the departure by 30 minutes, the flight would most likely have progressed safely in daylight conditions.

There are numerous airports in Australia, including Roma, that have an abundance of ground lighting in one take-off direction but not another. This accident highlights the potential benefits of night visual flight rules and instrument-rated pilots considering the location of ground lighting when planning night operations.

Finally, the benefit of crash-activated emergency locator transmitters that include global positioning system-based location information, thereby providing for a timely emergency response in the event of an accident, is emphasised.

Inquests are separate to ATSB investigations

The Coroner formulated his findings and recommendations independently of the ATSB. The ATSB cannot speak for the Coroners findings. However, the ATSB supports the coronial process and in the interests of ensuring that safety information is made available to the broadest audience the ATSB is making this publication.

The Coroner's report is expected to be made available from the Coroner's Court of Queensland. Contact details are available at: www.courts.qld.gov.au/courts. Queries regarding the Coroner's findings should be directed to the Coroner's Court at Brisbane.

On 20 February 2013, the pilot of a Cessna 310 aircraft, registered VH‑TWN (TWN), arrived at Wagga Wagga Airport to conduct a freight charter flight to Albury and Corowa, New South Wales.

In preparation for the flight, the pilot reviewed the applicable weather forecasts and Notice to Airmen (NOTAM) on a computer. At that time, another company employee initiated a conversation with the pilot. The pilot completed his pre-flight preparations and the aircraft departed at 0730 for Albury.

Prior to 0800, four workers at the Corowa aerodrome commenced laying unserviceability cross markers on runway 05/23. The runway had been declared closed from 0800 to 1800 due to works in progress (WIP); runway 14/32 remained open.

At about 0810, TWN departed Albury for Corowa. When 19 NM and 10 NM from Corowa, the pilot reported broadcasting an inbound call on the common traffic advisory frequency (CTAF). The pilot broadcast additional calls on the CTAF advising he was on base and final for runway 23.

The workers at Corowa were in the process of placing the last unserviceability cross marker near the runway 05 threshold, when they observed TWN on final approach for runway 23. The workers vehicle was also positioned on the runway. The workers and vehicle vacated the runway.

At about 0825, TWN landed on runway 23. Immediately after landing, when about 90-120 m along the runway, the pilot observed an unserviceability cross marker on the ground.

The workers were monitoring the CTAF on a hand held radio, but no broadcasts from TWN were reportedly heard.

This incident demonstrates the importance of maintaining a high level of vigilance, even when conducting familiar tasks; and the unexpected nature of distractions and the impact they can have on pre-flight preparations.

Aviation Short Investigation Bulletin - Issue 19

What happened

At about 1207 on 21 March 2013, a Robinson Helicopter Company R44 helicopter (R44), registered VH-HWQ, landed at a grassed area adjacent to a function centre at Bulli Tops, New South Wales. Shortly after landing, the helicopter was observed to simultaneously lift off, yaw right through 180° and drift towards nearby trees. The helicopter struck branches of the trees before descending, impacting the ground nose low and rolling onto its right side. A short time after coming to rest a fire started and engulfed the helicopter. The pilot and three passengers were fatally injured.

What the ATSB found

The circumstances of this accident were consistent with the helicopter lifting off following a deliberate or inadvertent collective input. The helicopter’s main rotor blades subsequently contacted nearby trees resulting in a loss of control and impact with the ground. The impact sequence resulted in a substantial fuel leak that was followed by an intense fire. This accident was similar to two other relatively recent fatal accidents in Australia involving R44s fitted with all-aluminium fuel tanks in which there was a fatal post-impact fire (PIF) following an otherwise survivable impact. Statistical analysis of helicopter accidents that occurred in Australia and the United States (US) between 1993 and 2013 identified a significantly higher proportion of PIF involving R44s than for other similar helicopter types. That analysis also identified that, despite the introduction of requirements for newly certificated helicopters to have an improved crash-resistant fuel system (CRFS) some 20 years previously, several helicopter types were still being manufactured without a CRFS and that many of the existing civil helicopter fleet were similarly not fitted with a CRFS.

What's been done as a result

Following this accident the Civil Aviation Safety Authority (CASA) took action to increase compliance with the helicopter manufacturer’s Service Bulletin 78B (SB-78B), requiring the fitment of bladder-type fuel tanks and other fuel system improvements. While recognising the action taken by CASA, due to concern that a significant number of Australian owners and operators had at that stage not taken steps to comply with the service bulletin, and were very unlikely to be able to do so by the required date of 30 April 2013, the ATSB released safety recommendation AO-2013-055-SR-001 to CASA that further action be taken. In response CASA released airworthiness directive AD/R44/23 requiring all owners of R44 helicopters in Australia to comply with SB-78B by the required date. Several other national airworthiness authorities (the South African Civil Aviation Authority, the Civil Aviation Authority of New Zealand and the European Aviation Safety Agency) subsequently mandated compliance with SB-78B. At the time of publishing this report the State of Design and Manufacture of the R44 helicopter had not mandated compliance with SB-78B.

The ATSB has issued a safety recommendation to the US Federal Aviation Administration (FAA) that they take action to ensure all R44 operators and owners comply with the manufacturer's Service Bulletin SB-78B and fit bladder-type tanks to improve resistance to post-impact fuel leaks. In addition, the ATSB also recommend that the FAA and European Aviation Safety Agency take action to increase the number of existing and newly-manufactured helicopters that are fitted with a crash-resistant fuel system.

Safety message

This accident highlights the catastrophic consequences of fuel-fed post-impact fire and that the most effective defence is to prevent the fire from occurring at impact by containing the fuel on board, preventing ignition, or both. In that context, the ATSB strongly encourages the fitment of a crash-resistant fuel system where possible.

On 19 March 2013 at about 1016 Eastern Daylight-saving Time, the pilot of a Cessna 172S aircraft, registered VH‑EUH (EUH), made a 10 NM inbound broadcast on the Point Cook CTAF advising that he intended to track overhead Point Cook for Avalon at 2,500 ft. The pilot was also monitoring the Melbourne Centre frequency

At about the same time, a Piper PA‑44‑180 aircraft, registered VH‑TYS (TYS), became airborne at Point Cook, for an IFR training flight. The pilot under training was flying under the hood and the instructing pilot was making all radio calls to Melbourne Centre and broadcasts on the CTAF. The flight crew of TYS did not hear the 10 NM CTAF broadcast made by EUH.

As TYS tracked southbound about 3 NM east of Point Cook and passing about 2,000 ft on climb to 3,000 ft, the instructing pilot deselected the CTAF. The pilot flying then turned right to track in a northerly direction, in anticipation of an airways clearance to enter Melbourne controlled airspace.

At about the same time, as EUH passed abeam Point Cook to the north-west, the pilot broadcast that he was leaving 2,500 ft for 4,500 ft.

At 1022, as TYS was levelling off at 3,000 ft about 1 NM west of Point Cook and in uncontrolled airspace, the instructing pilot looked to the right and observed a C172 in their 2 o’clock position about 100 m away at the same level. He called ‘taking over’ and immediately pushed the control column forward to descend below the traffic. The C172 flew about 50 to 100 ft above and about 9 to 12 m behind TYS. The instructing pilot then climbed the aircraft to 3,000 ft and the flight continued with no further incident.

The pilot of EUH reported that he did not see TYS.

A pilot of another aircraft operating in the Point Cook circuit at the time reported hearing a broadcast by EUH on the CTAF.

The ATSB often receives reports from pilots that another aircraft is flying too close to them in uncontrolled airspace. Three quarters of these reports involve pilots flying within 10 NM of a non-towered aerodrome. As a result, the ATSB has highlighted safety around non-towered aerodromes as one of its SafetyWatch priorities.

The ATSB publication A pilot’s guide to staying safe in the vicinity of non-towered aerodromes, AR‑2008‑044(1), noted that over 200 occurrences between 2003 and 2008 were found where pilots flying within 10 NM of a non-towered aerodrome may not have been broadcasting or maintaining a continuous listening watch on the CTAF.

Broadcasting on and monitoring the CTAF are key ways for pilots to establish traffic awareness, in the vicinity of non-towered aerodromes. The ATSB’s Limitations of the See-and-Avoid Principle study has shown that the effectiveness of a search for other traffic is eight times greater under alerted see-and-avoid circumstances, when a radio is used effectively in combination with a visual lookout, than when just un-alerted, when no radio is used.

Aviation Short Investigation Bulletin Issue 20

On the evening of the incident there were six aircraft in the circuit, including two Cessna 172 aircraft (C172). Both aircraft were engaged in flying training, one a dual flight (dual C172) and the other solo (solo C172).

The pilot of the solo C172 was instructed to follow the preceding aircraft, the dual C172. As the solo C172 approached the position where the pilot normally turned from downwind onto base, the pilot looked to the left and identified what he thought were the flashing lights of the aircraft he had been instructed to follow. The turn brought the solo C172 onto a base leg inside that of the dual C172.

Approaching the position where he was to turn onto final, the pilot of the solo C172 again misidentified the aircraft he had been instructed to follow. As the pilot of the solo C172 levelled out on final, ATC queried whether he still had the aircraft he had been instructed to follow in sight. Before he could answer, the instructor pilot of the dual C172 transmitted he was descending. After acknowledging the dual C172, ATC instructed the pilot of the solo C172 to go-around.

As a result of this occurrence, the operator of the solo C172 has advised the ATSB that they have implemented a night-flying checklist to record details briefed to students on expected flight conditions and traffic densities. Also, as a result of this occurrence, the operator of the dual C172 has implemented a procedure to liaise with other training organisations at Moorabbin to determine the number of aircraft programmed for night circuits.

A review conducted by the ATSB found that most of the midair collisions in Australia had occurred in the circuit area, and a high proportion of those on the final approach or the base-to-final turn. Though the review noted that there was a wide variety of contributing factors in the collisions with no dominant factors, the circumstances of a majority of the collisions were consistent with the inherent difficulties in sighting aircraft in time to avoid a collision.

Aviation Short investigation Bulletin Issue 22