| Date: | Tuesday 4 October 2022 |
| Time: | 15:10 |
| Type: | Bell 206 L3 Long Ranger |
| Owner/operator: | SIL Aviation |
| Registration: | P2-SIL |
| MSN: | 51511 |
| Year of manufacture: | 1991 |
| Total airframe hrs: | 8049 hours |
| Engine model: | Rolls-Royce 250-C30P |
| Fatalities: | Fatalities: 0 / Occupants: 6 |
| Other fatalities: | 0 |
| Aircraft damage: | Substantial |
| Category: | Accident |
| Location: | Aiyura National High School -
Papua New Guinea
|
| Phase: | Take off |
| Nature: | Passenger - Non-Scheduled/charter/Air Taxi |
| Departure airport: | Aiyura National School |
| Destination airport: | Lae-Nadzab Airport (LAE/AYNZ) |
| Investigating agency: | AIC PNG |
| Confidence Rating: | Accident investigation report completed and information captured |
Narrative:A Bell 206 L3 helicopter, registered P2-SIL, owned and operated by Summer Institute of Linguistics (SIL) Aviation, was conducting a VFR charter flight from Aiyura National School, in Ukarumpa, to Nadzab
Airport, Lae, Papua New Guinea when, during take-off, the tail rotor struck a power line. The helicopter was subsequently landed without further event.
Causes [Contributing factors]
- The pilot taxied to his nominated departure position which was unbeknownst to him. Within collision proximity of suspended powerlines where during a turn to line up for departure, the tail rotor blades struck one of the powerlines.
- The distance at which the pilot was assessing the powerlines was considered too far to
accurately judge distance.
- The powerlines, with the surrounding environment, presented an optical illusion which caused the pilot, at the distance from which he was observing the powerlines, to perceive.
- The erroneous perception resulted in misguided decisions.
- The high workload on the day would have caused a reduction in attentiveness and vigilance.
- The reduced effectiveness of the pilot’ scan and continued verification of initial perceptions made it difficult to detect perception of the powerlines were further away than they actually were.
- The departure position was selected by the pilot during pre-flight obstacle assessment following the erroneous perception of the observed powerlines position.
- The pilot perceived the suspended powerlines to be further away from the field than they were. The pilot assessed the powerlines and judged the powerlines distance from a distance that the normal human eyes are considered not reliable for accurately determining distance.
- The pilot was not aware of the actual environment and his cognitive limitation which led to a strong sense of full situational awareness. This affected the pilot’s ability to maintain a vigilant look out to verify the environment for any unsafe situations.
- The investigation considers that the fact that the pilot worked through a full day with activities still ahead, the pilot may have been fatigued and reduced vigilance and attention.
Accident investigation:
|
|
| | |
| Investigating agency: | AIC PNG |
| Report number: | AIC 22-1003 |
| Status: | Investigation completed |
| Duration: | 1 year 1 month |
| Download report: | Final report
|
|
Sources:
AIC PNG
Revision history:
| Date/time | Contributor | Updates |
| 22-Oct-2022 09:57 |
harro |
Added |
| 05-Nov-2022 09:54 |
harro |
Updated [Time, Nature, Departure airport, Destination airport, Source, Damage, Narrative, Category, ] |
| 27-Nov-2023 18:57 |
harro |
Updated [Other fatalities, Source, Narrative, Accident report, ] |
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