Collision with terrain

What happened

On 27 March 2014 the pilot of a Robinson R22 helicopter, registered VH-HRX, departed from Mullapunyah station, Northern Territory, for a short flight to the north-west. About 10 minutes after departure the pilot radioed that the drive v‑belts had failed and the station owner, in another R22, saw the helicopter enter a steep descent.

Soon after, the station owner found the helicopter complete and upright in a relatively clear area. The pilot of VH-HRX, who was laying a few metres from the helicopter, had sustained a serious head injury. The station owner tended the casualty and alerted emergency services at Borroloola of the accident, as well as personnel at the station homestead. Station personnel accessed the accident site over the rough terrain and started to transport the injured pilot on the back of a utility vehicle. The casualty was later transferred to a Bell 206 Jetranger helicopter for transfer to Macarthur River Mine. An aeromedical service then transported the injured pilot to Darwin where he was hospitalised for a number of weeks.

What the ATSB found

During the initial engine start/clutch engagement process following an extended period of static belt stretching, one or both rotor drive v-belts were displaced on the lower sheave with consequent increase in v-belt slack. Although the pilot, who was not qualified to conduct such maintenance, adjusted the clutch actuator to correct the excessive v‑belt slack, the v-belt displacement went undetected. While being operated in that abnormal configuration, one of the belts weakened and failed with consequent failure of the remaining belt, loss of drive to the rotors, and a forced landing.

Although Robinson Helicopter Company Safety Notice SN-33 provided guidance to pilots on how to stretch new v-belts statically, it did not specifically warn pilots that this process can increase the risk of belt displacement during the subsequent start.

Safety message

This accident highlights that in addition to having a good working knowledge of Robinson Helicopter Company Safety Notice SN-33, R22 pilots and engineers should be especially aware that, if the rotors do not turn within 5 seconds after clutch engagement, it is critical to perform the shutdown procedure and check the slack and position of the v-belts on both the lower and upper sheaves, before flight.

Pilots and operators of helicopters should also consider the residual risk of their operation and the benefit of occupants wearing helmets to reduce the risk of head injury in the event of an emergency landing.

On 22 March 2014, the pilot of a Robinson R22 helicopter, registered VH-YPS, was conducting aerial mustering on a property about 28 km east of Fitzroy Crossing aerodrome, Western Australia. The pilot had refuelled the helicopter from a jerry can and then secured the empty can in the passenger seat using the seatbelt.

At about 1530 Western Standard Time, the pilot manoeuvred the helicopter to the rear of a mob of cattle. From about 300 ft above ground level (AGL), the pilot conducted a balanced descending turn.

When at about 10 ft AGL, he applied right pedal and as he raised collective to climb away, a gust of wind blew through the left door opening and dislodged the jerry can from the seatbelt. The can became wedged between the seat and the cyclic control. The pilot applied forward cyclic, and the nose of the helicopter lowered. As he then attempted to apply aft cyclic to raise the nose, he realised the cyclic was jammed. With the low nose attitude and minimal height above the ground, the pilot used collective in an attempt to flare the helicopter. The front of the landing skids collided with the ground and the helicopter rotated forwards. The main rotor blades chopped through the tail boom and the helicopter continued rotating forwards and bounced back up to about 50 ft AGL before coming to rest inverted.

The pilot reported that the impact dislodged the top of the front dashboard and struck his helmet. He was uninjured and the helicopter sustained substantial damage.

This incident highlights the importance of ensuring all items are securely stowed. It also provides a timely reminder to pilots of the benefits of safety equipment such as a helmet.

Aviation Short Investigations Bulletin - Issue 30

At about 0700 Eastern Standard Time[1] on Sunday 2 March 2014, the pilot of an amateur-built Van’s Aircraft RV-6, two-seat aeroplane, registered VH-ZMH and operated in the ‘Experimental’ category, took off from Gatton Airpark, a privately operated airstrip located about 4 km south-west of Gatton township, Queensland. The pilot conducted about 20 minutes of local area flying in the aircraft prior to returning to the airpark with no indications of any technical problems or issues with the aircraft or its systems. The aircraft was then seen to be operating at a low level over the airstrip.

A number of nearby witnesses described seeing the aircraft flying at about 20‑50 ft above the airstrip at a speed higher than that required for a normal landing or missed approach. Those witnesses also heard the aircraft and described the engine sound as ‘normal’. The aircraft was then observed to climb at a nose-up pitch attitude of about 10‑20° and commence a left roll.

The aircraft then lost height and collided with terrain at a high rate of descent. The aircraft was destroyed and the pilot was fatally injured.

Pilot information

The pilot held a Civil Aviation Safety Authority (CASA) student pilot licence and a Recreation Aviation Australia Incorporated pilot certificate. The pilot did not hold qualifications that entitled him to fly the aircraft as pilot in command.

The CASA Civil Aircraft Register indicated that the aircraft was registered to another person; however, it was likely that accident pilot had purchased and flown the aircraft for several years prior to the accident.

Recorded data

Images from security surveillance recordings from commercial premises adjacent to the airpark captured the aircraft shortly before its impact with terrain. These images showed the aircraft descending at a high rate of descent in a right‑wing low attitude immediately prior to colliding with terrain.

Wreckage examination

Examination of the aircraft wreckage identified no mechanical issues or faults with the aircraft that may have contributed to the accident. Ground impact marks showed that the aircraft’s right wing initially collided with terrain followed by the main landing gear wheels (Figure 1). The distance between the wheel marks was greater than the normal static dimension between the wheels, which indicated a significant downward load during the impact sequence.

The ground impact marks and the witness reports were consistent with the pilot performing a low‑level ‘roll’ aerobatic manoeuvre at a height from which recovery to normal flight was not completed before the aircraft collided with terrain.

Figure 1: Ground impact marks showing the impact sequence

Data gathered in support of the investigation is being analysed in terms of the scope of any continuing investigation. That analysis is anticipated for completion in June 2014.

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The information contained in this web update is released in accordance with section 25 of the Transport Safety Investigation Act 2003 and is derived from the initial investigation of the occurrence. Readers are cautioned that new evidence will become available as the investigation progresses that will enhance the ATSB's understanding of the accident as outlined in this web update. As such, no analysis or findings are included in this update.

On 22 February 2014, the pilot of a Robinson R44 helicopter, registered VH-UGR, was conducting aerial agricultural operations on a property near Yass, New South Wales.

After successfully completing five loads of spraying, the helicopter was refuelled and reloaded with chemical for the next flight. The wind at the time was light and variable but favouring a southerly direction and the pilot manoeuvred the helicopter to take off towards the south. During the take-off, when at about 3 ft above ground level (AGL), the pilot reported that the helicopter was not climbing as expected and he thought that the wind had veered to a more westerly direction.

He commenced a right pedal turn towards the west, and down the slope, in an attempt to gain translational lift. The pilot reported that the wind had actually turned more easterly, and the helicopter therefore had a tailwind.

The low rotor revolutions per minute (RRPM) warning horn sounded and the pilot jettisoned the chemical load. The helicopter was then about 5 ft AGL, and the pilot was attempting to gain lift, and concentrating on keeping the helicopter straight in order to keep the landing skids level. He sighted a dry creek bed ahead and attempted to gain altitude prior to crossing it.

The helicopter was about 40-50 m beyond where the load had been jettisoned, and the pilot was focused on gaining lift, when the left skid contacted the ground, and the helicopter rolled over.

This incident highlights the importance of assessing options in case of reduced aircraft performance on take-off.

Aviation Short Investigations Bulletin - Issue 29

On 23 February 2014, a Hughes 269C helicopter, registered VH-HAK, was parked on a property about 55 km north-east of Launceston, Tasmania, beside a dam. The pilot had shut the helicopter down in that position about a week earlier, aware that it was low on fuel.

At about 0700 Eastern Daylight-savings Time (EDT), the pilot prepared for a short 200 m flight to reposition the helicopter to the other side of the dam, for refuelling. He conducted fuel drains, with no contaminants found.

The helicopter took off and climbed to about 20 ft above ground level. When about three quarters of the way across the dam, the engine stopped due to fuel exhaustion. The pilot conducted a forced landing onto the edge of the dam, with part of the helicopter sinking into the water and mud. The main rotor blades collided with the embankment resulting in substantial damage.

While experience and familiarity with operations are invaluable, they can also lead to complacency. It is therefore important that pilots with experience, familiarity and comfort with the aircraft and location, continue to do all checks thoroughly.

Aviation Short Investigations Bulletin - Issue 29

On 18 February, 2014 an instructor from a local flying school at Moorabbin Airport, Victoria, conducted a trial instructional flight (TIF) in a Cessna 150, registered VH-RXM.

As the aircraft taxied to the runway holding point, ATC advised of a 3-4 knots tailwind on the duty runway, 35 Left (L).  Although the wind was now southerly, the instructor was satisfied it was still acceptable to safely depart on this runway.

The flight was intended to give the student a “hands-on” experience at flying an aircraft. During the take-off, the student slowly advanced the throttle to attain full power, and then applied back pressure to the control column during the rotation and initial climb. These actions were monitored by the instructor. To enhance the “flight experience” for the student, the instructor had minimal input. He did however, maintain full control of the rudder pedals, and took control of the throttle lever once the student had applied full power.

During the initial climb, the student continued to apply back pressure to the control column resulting in a reduction in optimal airspeed, and a higher than normal aircraft nose attitude. As the instructor attempted to rectify the aircraft’s profile, the right wing dropped and the aircraft began to descend.

The instructor’s efforts to recover the aircraft to a normal climb attitude were not successful, and the right side of the aircraft struck the ground. The aircraft bounced, then came to a halt on its left side.

The instructor and student egressed through the right door. They both sustained minor injuries.  The aircraft was substantially damaged.

As a ‘Safety Action’, the flying school have changed their procedure in regard to trial instructional flights.

Instructors will now complete the take-off and initial climb to a height of 300 ft.

Aviation Short Investigations Bulletin - Issue 31

At about 0700 WST on 4 February, 2014 a student pilot departed Merredin Aerodrome, Western Australia for his first solo flight to the training area. He was flying a Grob G-115 aircraft, registered VH-BFW (BFW).

The wind was a light easterly when he departed to the north from runway 10.  When the training area practice sequences were completed, he returned to the aerodrome by overflying the airfield at 3500 ft, prior to joining the circuit. He noted the windsock now indicated a left crosswind, but as there was already an aircraft landing on runway 10, he elected to continue and join for this runway.

After completing crosswind, downwind and base legs of the circuit he configured the aircraft for the final approach and landing, including selecting full flap. As he commenced the round out, he realised the aircraft was about 15-20 ft above the ground and too high to continue with the landing, so commenced a go around. He applied full power and a small amount of rudder, but mindful of a previous instruction not to move the elevator forward while close to the ground, did not make any other changes to the aircraft configuration.

The application of power caused the nose of the aircraft to rise. It then encountered a gust of wind, which pushed the nose even higher, with a resultant loss of airspeed. The stall warning started to sound and the aircraft began to sink. The student attempted to recover the aircraft from the stall, but shortly after, the left wing struck the ground. The aircraft bounced back into the air and struck the ground again. The student was not injured but the aircraft was substantially damaged.

As a result of this accident, and to maximise safety at the flying school, management have split the Safety and Quality Manager position into two distinct positions. This will allow each incumbent to work separately, to maximise safety at the flying school. Management have also briefed all flight instructors on the importance of using correct phraseology when briefing and teaching students; as well as the importance of their role to ensure a safe environment for the students.

Aviation Short Investigations Bulletin - Issue 30

Section 21 (2) of the Transport Safety Investigation Act 2003 (TSI Act) empowers the Australian Transport Safety Bureau (ATSB) to discontinue an investigation into a transport safety matter at any time. Section 21 (3) of the TSI Act requires the ATSB to publish a statement setting out the reasons for discontinuing an investigation.

On 6 January 2014 at 1808 Coordinated Universal Time (UTC), a GippsAero GA8 Airvan aircraft, registered F-ORPH, was destroyed when it collided with terrain shortly after take off from Félix Eboué Airport, Cayenne, French Guiana. The pilot had returned for maintenance due to an engine problem during an initial take off attempt. The collision occurred after the pilot declared a MAYDAY two minutes after a second take off. One occupant was seriously injured while the other suffered minor injuries.

As the accident occurred in an overseas department of France, the Bureau d'Enquêtes et d'Analyses pour la sécurité de l'aviation civile (BEA) of France is responsible for investigating this accident. In accordance with international convention, the BEA notified the Australian Transport Safety Bureau (ATSB) as Australia is the State of Manufacture of the aircraft. In accordance with clause 5.18 of Annex 13 to the Convention on International Civil Aviation, the ATSB appointed an accredited representative to liaise with the BEA and initiated an investigation under the Australian Transport Safety Investigation Act 2003.

Given the time since the accident took place and that the BEA has not requested any assistance from Australia, the ATSB has decided to discontinue its investigation.

On 31 December 2013, at about 1230 Eastern Daylight-savings Time, a Grumman G-164A aircraft, registered VH-CCF, took off to the west, from an airstrip about 18 km north of Deniliquin, New South Wales, to conduct aerial spraying spreading operations.

The pilot reported applying a higher power setting than normal for take-off to allow for the warm temperature (about 25 ˚C) and short airstrip. When at about 150 ft above ground level (AGL), the pilot levelled the aircraft off and commenced a right turn towards the north. During the turn, the pilot felt the aircraft sink. The pilot rolled the wings level and elected not to jettison the chemical fertilizer load at that time as the aircraft normally stopped sinking once the wings were level. However, the aircraft continued to sink, and the pilot then jettisoned the load.

When at about 20-30 ft AGL, with a nose high attitude, the pilot felt the aircraft’s wings shaking, indicating an imminent stall. The pilot increased engine power in an attempt to avert the stall, but the aircraft continued to descend. Shortly after, the wheels touched down in a rice paddy in about 20 cm of water and the aircraft flipped over. The aircraft was substantially damaged, and the pilot was uninjured.

Aviation Short Investigation Bulletin Issue - 27

On 30 March 2013, a Beechcraft Baron G58 aircraft, registered N254F,with two persons on board, took off from Ardmore Aerodrome, New Zealand on private instrument flight rules (IFR) flight to Timaru, New Zealand. Shortly after the aircraft reached the intended cruise altitude of 18,000 feet (Flight Level 180), the aircraft began descending at a high rate and subsequently collided with the water. Both occupants were fatally injured.

The Civil Aviation Authority (CAA) of New Zealand is investigating the accident. On 11 December 2013, investigating officials contacted the Australian Transport Safety Bureau (ATSB) and requested assistance with the analysis of air traffic control audio recordings containing transmissions from the accident aircraft. To facilitate this assistance and protect the audio data and sensitive information received from the CAA, an external investigation was initiated under the provisions of the Australian Transport Safety Investigation Act 2003.

The ATSB has completed an analysis of the recordings and has provided the results of this analysis to the CAA of New Zealand.

Further information on the CAA investigation, including an interim factual report on the occurrence can be found on the CAA website, at:

www.caa.govt.nz, and
www.caa.govt.nz/Accidents_and_Incidents/Accident_Reports/N254F-interim.pdf

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Released in accordance with section 25 of the Transport Safety Investigation Act 2003.