AD/ML-M4/6 - Wing Inspection Holes - Modification - CANCELLED

What this does: This document officially cancels a 40-year-old safety rule (called an Airworthiness Directive or AD) that previously required owners of Maule M-4 series aircraft to install special inspection panels in the wings.

Who it affects: Owners and operators of Maule M-4 series aeroplanes. In practice, this affects nobody today because the original rule required immediate compliance back in 1969, meaning all affected aircraft would have been modified decades ago.

Why it matters: The cancellation removes an obsolete compliance burden from the books. The original rule was created to let aircraft mechanics inspect the wing spars (the main structural beams inside the wings) for corrosion or damage. Because this safety work would have been completed on all affected planes long ago, the rule is no longer needed and has been scrapped to tidy up the regulations.