AD/PA-31/38 - Heater Solenoid Shut-Off Valve - Modification - CANCELLED

This document officially cancels a former safety rule (called an Airworthiness Directive or AD) that applied to specific Piper aircraft models (the PA-31 series).

What the rule originally required Between 1975 and 2008, owners of these aircraft had to complete a one-time modification to the heater solenoid shut-off valve—a component that controls fuel flow to the cabin heater. Operators had to carry out this fix within 100 hours of flying time after December 1975.

Why it was cancelled The Civil Aviation Safety Authority terminated this requirement on 31 July 2008 because every affected aircraft had already undergone the required modification. The rule had achieved its safety purpose and was no longer needed.

Who this affects Owners and operators of Piper PA-31 series aeroplanes. Since the directive is now cancelled, no further action is required regarding this specific heater valve modification.