AD/GENERAL/51 - Electrical External Power Connection - Inspection - CANCELLED

What this does: This document officially cancels a 1975 safety rule (Airworthiness Directive 51) that required inspections of aircraft electrical external power connections.

Why it existed: The original rule was designed to prevent ground crews from accidentally connecting external power sources with reversed polarity (positive and negative wires swapped) to an aircraft's electrical system, which could damage sensitive avionics and electrical components.

Why it's being cancelled: Modern aircraft are now built to design standards that already include built-in protection against reverse polarity connections. Since the safety protection is now embedded in how aircraft are manufactured, the separate inspection requirement is no longer necessary.

Who it affects: Aircraft operators and maintenance engineers who previously had to comply with this specific inspection requirement for external power connections.