The pilot of a Cessna Skylane (C182) was preparing to conduct a private flight with three passengers. The pilot reported that the planned work-related flight was the first following a periodic maintenance inspection. After carrying out a pre-flight inspection, the pilot and passengers boarded the aircraft. The pilot ensured that the passengers' harnesses were secured, and the right front seat occupant was briefed to not touch the controls. The pilot switched on the aircraft's electrical power to use the radios in order to obtain the broadcast aerodrome information and an airways clearance. The pilot estimated that electrical power was drawn from the aircraft's battery for approximately two minutes during which time he made several radio transmissions. When he attempted to start the engine, battery power was depleted, and the electric starter would not turn the propeller.
The pilot reported that he then applied the parking brake and set the engine controls. After again instructing the passengers not to touch the aircraft controls, the pilot alighted and attempted to start the engine by hand swinging the propeller. On the second compression the engine started and accelerated to nearly full power. The aircraft moved forward and accelerated rapidly across the apron. Other than the passengers, no other person was known to have seen the pilot attempting to hand start the aircraft. Personnel working in or around other aircraft parked on the apron were alerted to the occurrence by the sound of an aircraft engine at or near full power.
Witnesses saw the C182 accelerate across the apron pursued by the pilot. They reported that the C182 nearly became airborne before its wingtip struck the windshield of a parked Cessna 402. The C182 continued across the apron and collided with the rear of a parked Metroliner. The rear fuselage of the Metroliner was significantly damaged by successive strikes from the C182's propeller blades. That impact swung the C182 and it continued unchecked, before colliding with a Cessna 206 (C206) that was parked 120 m from where the C182 had started. The pilot chased after the aircraft and although he gained entry to the cabin, he was unable to stop the engine before the collision with the C206.
The collision collapsed the left wing of the C182, preventing normal operation of the left cabin door and the right cabin door was blocked by the C206 fuselage. The pilot forced the left door open to evacuate the passengers. Maintenance personnel who had witnessed the collision came to the assistance of the C182 occupants. During the evacuation sequence, spilled fuel from the ruptured wing tanks had soaked the aircraft occupants and rescuers. One passenger was injured from the force of the collision. All of the occupants and some of the rescuers received minor skin burns from contact with aviation fuel. The other aircraft struck were neither occupied nor had maintenance personnel working on them at the time. The Metroliner, C206 and the C182 were extensively damaged.
The licensed aircraft maintenance engineer who supervised the maintenance inspection of the C182 reported that the 24-volt, lead-acid battery had been removed from the aircraft and inspected. The inspection was performed in accordance with the battery manufacturer's directions and included checking for any discolouration of the electrolyte and topping up. The battery had been placed on a low charge rate for several hours to ensure it was fully charged. Following the occurrence, a test of the battery's capacitance found that, when fully charged, it took six minutes under normal load to discharge. The manufacturer's specification for the battery capacitance equated to an output of 13 amperes for 30 minutes. The battery had been in service for approximately three years.
Post accident inspection of the aircraft controls found the throttle in the fully open position and the throttle friction nut loose. The park brake handle was selected to the on position but not firmly applied. When checked, the park brake functioned normally. The pilot reported that he had not checked the throttle setting and could not account for the setting being anything other than the normal start position. He had applied the park brake but had not chocked the wheels or secured the aircraft with the tail tie-down.
Civil Aviation Regulation (CAR) 231-"Manipulation of propeller", permitted hand starting when assistance from a licenced pilot or appropriately qualified person was not readily available. Although the aircraft was positioned approximately 50 m from the maintenance facility that carried out the inspection, the pilot had not sought assistance from the engineering staff. The maintenance organisation reported that a battery cart was available and the aircraft was fitted with an external power source receptacle.
Additionally, CAR 231 required the person manipulating the propeller to know the correct starting procedures for the aircraft. When attempted, without assistance from another qualified person at the controls, the regulation required that adequate provision was made to prevent the aircraft from moving forward, and that no one was on board the aircraft. The pilot reported that he had been shown the hand starting technique during basic flying training about six years previously. The instructor had demonstrated the technique on a Cessna 150 training aircraft. Although the technique had been demonstrated during that training, the pilot could not recall being briefed on all of the safety precautions associated with hand starting procedures.