Sequence of Events
The aircraft commenced a normal takeoff. After becoming airborne, the pilot selected "wheels up." Because the undercarriage selector knob was sticking, the radio operator was asked to operate the undercarriage safety switch. The undercarriage retracted normally, but immediately after retraction, the aircraft sank and struck the runway. The pilot shut off power, and the aircraft slid at high speed for a considerable distance down the runway. A fire erupted, and the aircraft was almost completely destroyed. However, all passengers and crew evacuated safely before the aircraft was consumed by fire.
Pilot's Actions
The pilot-in-command stated in evidence that he had no knowledge of the airspeed at the time of undercarriage retraction but was satisfied that he had achieved safety speed. Despite the pilot's notes recommending 20 degrees of flap for takeoff, no flap was used. The pilot explained that he believed 20 degrees of flap would make the aircraft more difficult to handle on one engine in the event of an engine failure after takeoff. Evidence indicated that handling the undercarriage lever, which can be awkward to operate in Dove aircraft, may distract the pilot from flying.
Official Findings
The accident was attributed to a combination of factors. The aircraft was pulled off the runway after too short a takeoff run at low speed. The undercarriage was retracted too early, before safety speed was reached and while at very low altitude. The aircraft then sank back onto the runway before reaching safety speed. This may have been due to a thermal disturbance or distraction from the difficulty in retracting the undercarriage. The fire, which originated to the rear of the starboard engine nacelle, was possibly caused by fractured petrol pipes and electrical circuits. The pilot did not operate the engine nacelle fire extinguishers, which might have prevented the fire. The inertia switch for the static fire extinguishers did not operate due to slow acceleration. The airport fire tender arrived late because it took an unserviceable taxi track, and its crew's inexperience prevented optimal use of the foam. The fire eventually burnt itself out, resulting in near-total destruction of the aircraft.