On arrival in the destination area the pilot was unable to obtain a down and locked indication for the landing gear. An inspection from another aircraft indicated that the left gear was only partially extended and the pilot elected to divert to Bankstown. All further efforts to lower the gear fully by normal or emergency means were unsuccessful, and the gear ultimately jammed in the mid-position. A safe landing was subsequently made, with the aircraft touching down on a grass undershoot area and sliding to a stop on the selected runway. The pilot had been unable to extend the gear electrically because of a rigging fault in the nosegear mechanism. Manual extension had not been possible because of chipped edges on the tooth and slot of the hand cranking mechanism. The damage to the tooth and slot was considered to have resulted from some previous occasion, when the manual handle had inadvertently been left engaged during electrical operation of the gear. The crank handle, rotating at high speed, had probably come into contact with an object on the cabin floor.
