Airframe event involving a Piper PA-34-200, VH-ESY, Jerilderie, New South Wales, on 27 August 1993

The nose landing gear collapsed during the take off roll causing both propellers to strike the runway whilst operating at full power. Subsequent investigation revealed that a rigid hydraulic line had failed causing the loss of all hydraulic pressure. This lack of hydraulic pressure probably allowed vibrations to unlock the nose leg over-centre lock during the take off roll.

Examination of the failed hydraulic line revealed that there was thinning of the pipe wall at the failure where the pipe was supported by a 'P' clamp, possibly the result of corrosion. Significant Factors: Failure of a hydraulic pressure pipe, possibly due to corrosion, resulted in loss of all hydraulic pressure. The nose landing gear over-centre lock probably unlocked due to vibration.