A "stubby-type'' screwdriver found in the wreckage of plane which crashed in Feilding last month, killing two men, may have caused the crash, investigators say.
Queensland chiropractor Brett Ireland, 50, and Palmerston North doctor Ralph Saxe, 51, died when the small plane they were in crashed in Timona Park, about 35 minutes after taking off from the Taonui Aerodrome near Feilding on January 23.
Dr Saxe co-owned the Aerostar Yak 52TW; aircraft of its type are commonly used for aerobatics.
The Civil Aviation Authority (CAA) is investigating the crash and today said it was "following a line of inquiry that points toward a mechanical issue''.
"Investigators found a stubby-type screwdriver amongst the wreckage, which may have rendered the aircraft unflyable,'' the CAA said.
"While this cannot yet be concluded as the cause of the accident, it is of grave concern.''
The crash mirrored one in Britain in 2003 which also claimed two lives; a stubby-type screwdriver became lodged in the tail of the Yak 52 aircraft in that crash, affecting its controls.
The CAA had contacted all Yak 52 owners in New Zealand to advise them of the finding and to recommend a thorough inspection for foreign objects.
"Foreign object damage is a known risk to aerobatic aircraft. Any loose material, even a paper clip, can shift during aerobatics and affect the aircraft's controls,'' the CAA said.
It hoped to publish a preliminary report into the crash within three weeks.
Today's news came on the same day Dr Saxe was to farewelled in Feilding.