Background
On the afternoon of Friday 9 November 2007, the pilot of ZK-EGV, a turbine-powered agricultural aeroplane, began a task to spread 80 tonnes of superphosphate over a farm in low hills 5 km south of Opotiki township. The pilot was familiar with the farm and its airstrip. After 6 or 7 loads, the wind became too strong for top-dressing, so the pilot and loader-driver returned to their base at Whakatane aerodrome, about 40 km away. At Whakatane, the fuel tanks were filled. Later, the pilot replaced the display for the precision sowing guidance system, which had a software fault.
The next morning, 10 November 2007, the pilot bicycled about 6 km from his house to the aerodrome, arriving at about 0545. The loader-driver noted that the pilot looked “pretty tired” from the effort. After starting the aeroplane using its internal batteries, the pilot and loader-driver flew to a farm west of Whakatane to complete a task. The pilot’s notebook indicated that the task began at 0610 and required 45 loads to spread the remaining 68 tonnes of product, averaging 1511 kg per load. The loader-driver recalled that about 2 months earlier, the pilot had determined that the scales on the loader at that airstrip were “weighing light” by about 200 kg, so the loader-driver accounted for that difference.
Accident Sequence
After the Whakatane task, the pilot and loader-driver flew back to the farm south of Opotiki. A different loader with accurate scales was used, and the loader-driver loaded 1500 kg each time as requested. The fertiliser remaining in the storage bin after the accident was dry and free flowing. The sowing task at this farm began at 1010. The pilot stopped every hour to uplift 180 L of fuel (144 kg). During a refuel stop between 1226 and 1245, he had a snack and a drink. Sowing resumed at 1245 with about 3 minutes between loads; the last load was put on at about 1316. The loader-driver reported light wind and no problems reported by the pilot.
After the last refuel, the top-dressing was mostly out of sight of the loader-driver. When the aeroplane did not return for the next load, the loader-driver attempted to call the cellphone installed in the aeroplane 3 or 4 times. Unsuccessful, he followed the operator’s emergency procedure and called 111 at 1338 to report the aeroplane overdue. Telephone records showed that on 10 November, the aeroplane cellphone was connected for over 90 minutes on 14 voice calls and used for 10 text messages. The pilot initiated most calls by sending a message, and most calls involved a female work colleague who was a friend. The longest session exceeded 35 minutes. The friend stated the content of the last phone call was not acrimonious and that the pilot said he made calls to help stay alert.
At 1153, in a call to his home, the pilot indicated the job was going well and he might be home by 1400. In one call to the friend, he said he was a bit tired and hoped the wind would increase to force cancellation. At 1308:45, the friend called and talked with the pilot until the call disconnected at 1320:14. The friend said the pilot’s voice volume decreased slightly, then there was a “static” sound. The friend immediately called back but got the answerphone. Two further attempts failed. An orchardist working about 3 km away heard an aeroplane for hours, then a loud sound at 1320; he began searching. The Police organised an aerial search after the loader-driver’s emergency call, finding the wreckage at 1435 on the edge of a grove of native trees, approximately 600 m northwest of the top-dressing area. The pilot had been killed. His body was removed 26 hours later due to Police concerns not to disturb the wreckage until investigators arrived.
Investigation
The CAA began an investigation that day, and the Commission sent an investigator to assess similarities with another Fletcher accident. On 19 November 2007, due to potential regulatory oversight issues, the Commission started its own inquiry. The official findings noted that the reason for the collision was not conclusively determined. However, the pilot was affected by multiple fatigue-inducing factors, which combined with distractions from a prolonged cellphone call and a minor equipment failure were considered likely to have diverted his attention from monitoring the flight path. Pilot incapacitation could not be ruled out but was not considered directly contributory. The cellphone distraction during VFR flight was not specifically addressed by Civil Aviation Rules. No evidence suggested the aeroplane was unserviceable, but its airworthiness certificate was invalid due to missing post-flight checks of the vertical tail fin for the previous 3 days. The turbine engine installation had no effective de-rating system, but that was not considered contributory. The pilot was experienced and met competency requirements, but the last two checks were likely invalid. The aeroplane was overloaded before the accident but not at the time of the collision. The emergency locator transmitter did not radiate a useful signal due to damage to the antenna socket, and the installation was not in accordance with manufacturer’s instructions.