The Piper Chieftain was being flown as a single-pilot operation to conduct a scheduled passenger flight from Adelaide to Kingscote. The Chieftain was one of six aircraft being used by the operator on the route at the time. The other aircraft were involved in passenger charter operation. The six aircraft departed Adelaide at about the same time for Kingscote and the Chieftain was the first to approach the airfield.
The pilot reported that he decided, based on the Kingscote Automatic Weather Service reports and the weather forecast for the area, to descend to the sector's Lowest Safe Altitude. He intended to descend clear of cloud and approach the airfield to land on Runway 19 via a 5 NM straight-in visual approach. He had also planned to conduct a Sector A Global Positioning System (GPS) instrument arrival should the aircraft not break clear of cloud in sufficient time for a normal visual approach. Due to the weather conditions, the pilot decided to make the Sector A GPS arrival. The pilot reported that during the descent and approach, the pilots of the other aircraft were querying him about the cloud base and weather so that they could plan their arrivals.
The pilot reported that, during the GPS arrival, he had configured the aircraft in accordance with the operator's requirements and aircraft checklist, including lowering the landing gear. The aircraft broke clear of cloud at about 1,000 ft and 2 NM from the airfield. The pilot decided that the aircraft would require excessive manoeuvring to land directly from the approach and chose, instead, to conduct a left circling approach to Runway 19. He reported that he raised the landing gear to reduce the chance of large power changes that may have alarmed the passengers. He then flew the circling approach but did not lower the landing gear.
While the pilot was answering queries from other pilots about the weather conditions on the MBZ frequency, he was also listening to radio traffic on the ATC frequency. He also reported that there was light rain falling and running along the windscreen, reducing visibility and increasing his workload.
The pilot reported that late in the landing flare, he heard the landing gear warning horn and the scraping of the aircraft on the runway. He initiated a go around and advised the following aircraft of the event, however he did not receive a reply because the aircraft's VHF antennas had been damaged during the scrape on the runway. He then lowered the landing gear and landed without further incident on Runway 24 to help ensure separation from the following aircraft. The Chieftain sustained damage to both propellers, the VHF radio aerials on the underside of the aircraft fuselage and the inboard sections of the flaps.
The pilot was in a high workload situation, manoeuvring the aircraft in order to set it up for landing, and was probably distracted by the radio broadcasts and weather conditions at the time, which resulted in him forgetting to lower the landing gear before landing.