Collision with terrain

The aircraft was being operated on a regular freight carrying run between Dysart and Rockhampton. On the evening preceding the accident, the aircraft departed Dysart at 2045 hours, arriving at Rockhampton at 2139 hours. At 0222 hours on the following morning the pilot telephoned Brisbane Flight Service Centre to obtain an update on the weather for the return flight to Dysart. The forecast indicated that at the time of arrival at Dysart, light rain with 5 oktas of cloud at 700 feet above ground level, could be expected. The pilot nominated Rockhampton as the alternate for Dysart in the event that weather conditions at the latter aerodrome precluded a safe approach and landing. The aircraft was refuelled to give a total fuel endurance of 290 minutes, and after loading departed Rockhampton at 0354 hours. At 0435 hours, the pilot reported that descent had been commenced into Dysart and because of poor reception on High Frequency radio channels further communications with VH-CLU were relayed by another aircraft in the area, VH-EEF on Very High Frequency channels. After communications with VH-CLU, the pilot of VH-EEF advised Brisbane Flight Service Unit (FSU) at 0453 hours, that the runway lighting was not yet displayed. The runway lighting at Dysart was provided by a number of hand-lit flares. The lighting of these flares was carried out by an employee of the company operating VH-CLU, and normally took about ten minutes. On this occasion the employee had overslept and arrived at the aerodrome at about the same time that the aircraft flew overhead. At 0501 hours further attempts by the pilot of VH-EEF and Brisbane FSU to contact VH-CLU were unsuccessful. The wreckage of the aircraft was later located about 800 metres to the west of the aerodrome. The aircraft had struck trees while heading in a direction aligned with runway 14 but displaced to the west of the runway. It had been destroyed as a result of the impact forces. Witnesses reported that when VH-CLU arrived at Dysart it was not raining, however, low cloud was present. The aircraft was observed to complete three orbits of the aerodrome and at times during these orbits it was obscured by cloud. The only fault found with the aircraft during the investigation was a failed fuel pump on the right engine. It was established that the right engine was operating on impact and the failure of the fuel pump is not considered to have substantially affected the operation of the aircraft. The reason the aircraft crashed was not established.

The aircraft was cleared via a Standard Instrument DEPARTURE with an unrestricted climb to Flight Level (FL) 220. The aircraft climbed on track at an average rate of 1300 ft/min until FL130. The rate of climb then reduced to 350 ft/min until FL140, when the rate of climb increased to 1800 ft/min. At FL160 the aircraft entered a near vertical descent and radar contact was lost one minute later at 3100 feet. The aircraft impacted the ground in a near vertical attitude. Despite an extensive investigation, the reason for the loss of control leading to this accident could not be determined. There have been several other reported occurrences involving sudden loss of control in this aircraft type and the United States Federal Aviation Administration has conducted a certification review of the type. The results of that review do not appear to indicate any factors relevant to this particular accident.

Circumstances:

The aircraft was taking off shortly after the pilot had carried out modifications to the fuel system. This had included removing and replacing fuel lines. A witness reported that prior to commencing the take-off, the engine had been misfiring. This had continued during the take-off run and initial climb until the engine stopped at a height of about 150 feet. The aircraft was seen to turn sharply to the left before entering a steep nose down spin. After about one full turn the aircraft struck the ground near the strip end. The pilot, who was not wearing a helmet, suffered a fatal head injury following the failure of his upper body restraint on impact. The reason for the loss of engine power could not be positively determined.

Significant Factors:

The following factors were considered relevant to the development of the accident:

1. Undetermined loss of engine power after take-off.

2. Pilot attempted operation with known engine deficiency.

3. Pilot encountered circumstances beyond his capability.

Recommendations:

As a result of the initial investigation, the Australian Ultralight Federation was notified of the failure of the restraint system, together with a recommended solution. The AUF issued an Airworthiness Advisory on the subject in January 1990.

At the end of an uneventful flight from Morven the sole passenger disembarked and watched while the pilot restarted the engine and commenced to taxy. The passenger next observed the aircraft when it was about 30 ft above the ground after take-off. At this time the aircraft was steeply banked to the left and shortly after it passed from sight the engine noise ceased and the sound of trees breaking was heard. The wreckage of the aircraft was subsequently located at the threshold of another of the aerodrome strips. It was determined that the aircraft had collided with trees while it was in a left wing down attitude before rolling inverted and striking the ground. The precise cause of the accident could not be determined, however the possibility that the right wing flap was jammed in the fully down position after the previous landing could not be discounted.

Circumstances:

The pilot under check advised the tower controller that the pilot in command wished to demonstrate an engine failure after take-off from runway 33 and that they would land on runway 15. The controller gave approval for this sequence and issued a take-off clearance. Four minutes earlier, a Dash 8 aircraft had been cleared for take-off (this aircraft was making an intersection DEPARTURE) from the same runway. VH-CES was observed to turn back towards the runway and descend normally but contacted the ground adjacent to the runway right wing low and sideslipping to the right. The landing gear collapsed, and the aircraft came to rest facing north-east. Wind at the time was from 030` at 5-10 kts. The pilot reported that the aircraft had experienced a bump similar to that when encountering wake turbulence. The bump was encountered shortly after the aircraft commenced the turn back to the runway, and after the throttle was closed. The aircraft then experienced windshear and downdraft to the extent that the rate of descent could not be arrested before ground impact. VH-CES took off some 2-3 min after the Dash 8. Because the Dash 8 weighs less than 25,000 kg, no wake separation standard was required to be applied by the aerodrome controller. The wake produced by the Dash 8 right wing would, in nil wind conditions, travel away from the runway at about 5 kts. Under the crosswind conditions prevailing at the time, however, the wake could have remained in the vicinity of the runway. This, along with the significant weight difference between the two aircraft, could have led to the flight path of VH-CES being adversely affected.

Significant Factors:

The following factors were considered relevant to the development of the accident

1. Crosswind conditions prevailed.

2. Wake turbulence was generated by a departing aircraft.

3. The aircraft was probably affected by wake turbulence during approach.

Circumstances:

The aircraft was on a flight from Bandana Station Authorised Landing Area (ALA) to Gunnedah in company with two Airtourer 150 aircraft. Landings were planned at Roma, St. George, and Moree. VH-MVL took off first into a moderate south-westerly wind. After a long take-off roll the aircraft became airborne and, at low altitude, maintained runway heading for some considerable distance. During the completion of a 90-degree left turn, the aircraft failed to climb then entered a steep descent and crashed two kilometres south-west of the strip. Impacting the ground in a level attitude, the aircraft was destroyed and the two occupants seriously injured. The pilot's head struck the instrument panel when his shoulder harness restraint failed. The Bandana ALA is 820 metres long, aligned 04/22, and slopes two percent down toward the south-west. The surface is uneven and covered with long grass. About 3.5 kilometres to the west is an escarpment, almost 2000 feet high. The escarpment forms part of the eastern edge of the Carnarvon Range. In conjunction with the escarpment, the fresh, cool, and stable south-westerly airstream produced appropriate conditions for significant leeside downdraughts or standing waves. The pilot was very familiar with VH-MVL, having logged most of his experience on type in that aircraft. He had recent experience in operating from ALAs and had expressed some concern about take-off performance from Bandana. He considered flying VH-MVL to nearby Ingelara to load his passenger and baggage and then depart from its 1250 metre grass strip. He subsequently decided to depart from Bandana. The aircraft had been refuelled to 108 litres (24 Imperial gallons) at Emerald before the 74-minute flight to Bandana. Combined with the weights of occupants and baggage, the aircraft was 33 kilograms over maximum gross for take-off. Even at the highest rate of fuel consumption, the weight of the remaining fuel was sufficient to result in the aircraft being marginally over maximum gross weight for take-off from Bandana. The aircraft had been operating from other airfields with the two occupants, the baggage and fuel loads up to 108 litres. It seems likely that the critical terrain and meteorological conditions requiring performance beyond the aircraft's capability were not encountered until this flight. With their additional power the two Airtourer 150s were able to climb safely in the prevailing meteorological conditions. Examination of the aircraft and engine failed to reveal any pre-existing mechanical abnormalities which could be considered as factors contributing to the accident. Examination of the failed shoulder harness restraint cable revealed that one third of its steel wire strands had been broken or partially fatigued before the accident. The broken strands had paint on the fracture surfaces, indicating that they were broken before or when the aircraft interior was last painted. The number of intact strands was insufficient to absorb the loads in the impact, causing failure of the cable and serious head injury to the pilot.

Significant Factors:

The following factor was considered relevant to the development of the accident:

1. The aircraft, marginally above maximum gross weight, probably encountered downdraughts in the lee of the escarpment after take-off and was unable to establish a safe climb.

Circumstances:

When the survey aircraft failed to arrive at the destination, and on expiry of the SAR time, a search was commenced. Wreckage of the aircraft was subsequently found on the eastern slope of Mt Barren Jack, to the north west of the mouth of Carrolls Creek, and on the planned track for the survey operation. Observers at the Burrinjuck reservoir near the mouth of Carrolls Creek described the weather in the accident area at the time as black clouds spilling over and obscuring the mountain tops. The aircraft collided with trees on the side of the mountain, while banked steeply to the right and in a tail low attitude. The pilot was thrown from the aircraft during the impact sequence. Medical opinion held that there was no evidence of body trauma consistent with the seat belt being fastened at the time of impact. Because of the destruction of the aircraft by the ensuing fire the status of the seat belt assemblies were unable to be determined. The investigation revealed that both engines were operating at high power at the time of impact. No malfunction or defect could be found with the aircraft which could have contributed to the accident. The survey task required the pilot to adhere strictly to a particular track and the target height for the flight was 500 feet above ground level while maintaining visual contact with the ground at all times. The pilot was suitably qualified to act as pilot in command of survey operations down to a height of 200 feet above ground level. The investigation concluded that the aircraft was being operated at a height substantially lower that 500 feet above ground level prior to the accident. Impact marks, wreckage and mechanical evidence suggest that the aircraft impacted terrain at a time when the pilot was attempting to carry out an evasive manoeuvre to remain clear of terrain. The reason why the aircraft was being operated at such a height and why the pilot delayed turning away from the steeply rising terrain could not be determined.

Significant Factors:

1. The pilot continued the flight into adverse weather conditions.

2. The pilot flew the aircraft towards steeply rising terrain at a height substantially lower that 500 feet above ground level.

The pilot was employed as an aircraft salesman. He had previously been employed in the field of aircraft sales in the United Kingdom and the United States of America. During his time in the United Kingdom the pilot claimed to have performed flying displays at three air shows. After joining the company the pilot received training from another company aircraft salesman and was initially approved only to demonstrate aircraft to customers but not at airshows. When it became evident that several airshows were in the offing, the company had one of its experienced check and training pilots fly the planned airshow flying sequence with Mr Eberbach.

This check flight was completed to the check pilot's satisfaction on the afternoon of 4 February 1983 in VH-TBC. On 6/02/1983 the pilot completed the flying sequence at the Welshpool Air Show.The Maroondah Air Show was conducted at Lilydale on 13 February 1983 and 14-2-83. On 13 February 1983 after the completion of the air show briefing involving all participants, Mr Eberbach and another company pilot returned to the company caravan with the company's marketing manager. All three then conducted a detailed briefing on the sequence to be flown by Mr Eberbach, confirming heights and speeds for all manoeuvres to be flown. The display was then completed without any evident problems. On the morning of 14 February 1983 the pilot attended the air show briefing but as the same manoeuvres were to be flown as on the previous day no individual briefing was held. The weather conditions on the day were not ideal for display flying, with a temperature of 36 degrees Celsius and a northerly wind of about 10 knots with gusts up to 20 knots.

The turbulence was reported to have been moderate from the effect of thermals and trees on the airfield boundary. The pilot taxied VH-TBC to the holding point about ten minutes before his planned take-off time. After taking off, the display sequence was flown normally up until the final steep turn manoeuvres. The aircraft approached the airfield from the southwest at a height of approximately 200 feet above ground level and commenced a left turn at an angle of 60 degrees. The turn was continued through 360 degrees and then the aircraft was rolled into a turn to the right at a similar angle of bank. The aircraft appeared to climb slightly in the initial part of the turn to the right and after turning through 90 degrees the angle of bank increased to 100 degrees and the nose of the aircraft began to drop below the horizon. The aircraft then recovered to a wings level attitude, the nose of the aircraft was raised above the horizon, but the aircraft impacted the ground heavily on all three wheels. The wheels and right main plane broke off and as the aircraft slid forward the engine was torn from its mountings and lodged underneath the fuselage. The aircraft slid for a distance of 90 metres and turned through 180 degrees before coming to rest. Subsequent investigation did not disclose any fault with the aircraft that would have contributed to this accident.

Circumstances:

The pilot had planned the direct track for the flight from Cockatoo Island to Derby at 5500 feet above sea level. When the pilot gave his DEPARTURE call, he amended his cruising level to below 5000 feet. No further calls were received from the aircraft. The Cockatoo Island work boat was 56 kilometres north-north-west of Derby, and approximately 20 kilometres west of the direct track between Cockatoo Island and Derby. The crew of the boat observed an aircraft approaching at very low level. The aircraft passed over the boat approximately 5-7 metres above the deck and entered a right hand turn. During the turn the right wing tip struck the water causing the aircraft to cartwheel and crash about 400 metres from the boat. The fuselage broke open on impact and the occupants were subsequently rescued by the crew of the boat. The pilot declined to provide any information which might have clarified the circumstances of the accident, however, available information indicates that he carried out an unauthorized low pass over the boat. During the turn following the low pass, he misjudged the aircraft's height and the right wing tip struck the water.

Significant Factors:

The following factors were considered relevant to the development of the accident:

1. The pilot was neither trained nor authorized to conduct operations at low level.

2. The pilot exercised poor judgement by operating at an unnecessarily low height.

3. The pilot misjudged his height above the water.

The King Island aerodrome weather was forecast to include temporary periods of moderate to heavy rain showers, six eighths of cloud cover base 800 feet and visibility reduced to 3000 metres. The forecast surface wind was 340 degrees at 20-30 knots. The pilot's qualifications required a minimum visibility of 5000 metres for operation at night in Visual Meteorological Conditions, (NGT VMC). It was planned that another pilot, qualified for Instrument Flight Rules (IFR) operations, would act as pilot in command, but he became unavailable. The flight plan submitted by the pilot indicated he would be operating under the IFR category and when queried on taxiing he confirmed that this was so. Shortly after DEPARTURE, the pilot requested a weather report from an IFR pilot who had just landed at King Island. This gave a cloud base of 2000 feet, heavy rain showers and visibility of 2000 metres. Flares had been laid to allow the other pilot to use Runway 35 because of the strong northerly wind. The pilot of VH-CAY activated the electric lighting for Runway 28. He reported that the weather was satisfactory enroute and he could see lights ahead on the island. On crossing the coast flight conditions became rough in moderate to severe turbulence. The pilot advised he arrived over the aerodrome at 1500 feet above mean sea level and observed the lighted wind sock was horizontal, with the direction fluctuating rapidly between north and west. He turned to the south and broadcast his intention to land on Runway 28. Neither the pilot nor the passenger had any further recall of the events leading to the accident. VH-CAY was heard passing over the aerodrome and the engine sound was very loud, suggesting to the listener that the aircraft was low. It had been raining continuously for more than an hour, sometimes very heavily, and it was still raining at the time. The aircraft was subsequently seen flying at a very low height some six kilometres south of the aerodrome, tracking approximately north. It was raining very heavily in that area and the wind was very strong. Soon afterwards there was a sound of impact and a flash of light. The aircraft had struck the tops of trees 30 feet high, then descended to the ground. After the aircraft came to rest it was destroyed by a fire. Examination of the wreckage was severely hampered by the extreme fire damage sustained, but no evidence was found of any defects that might have contributed to the accident. The aircraft had evidently been under control at the time it collided with the trees. A post analysis of the conditions by the Bureau of Meteorology indicated the possible presence of strong up and down drafts, horizontal wind shear, turbulence, and estimated visibility as 2-3000 metres in rain. The evidence suggested that the pilot may have been lower than he believed as the aircraft overflew the aerodrome. Having passed overhead, there there would have been few external visual references under the existing conditions to alert him that the aircraft was inadvertently being descended into the ground.