COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 107 CIVIL AVIATION SAFETY AUTHORITY
SCHEDULE OF AIRWORTHINESS DIRECTIVES
Electrical Equipment
AD/ELECT/6 Magneto - BTH - Contact Breakers NK
Assembly - Modification
Applicability: All BTH type AG4, SG4 and MC1 magnetos fitted with contact breaker assemblies incorporating an automatic earthing device which short circuits the magneto primary winding when the contact breaker cover is removed.
Requirement: 1. Remove the automatically earthing type contact breaker assembly and:
(a) Replace with a contact breaker assembly which does not have provision for automatically earthing the magneto primary winding; or
(b) Modify the existing contact breaker assembly by removing the automatic earthing features.
2. Reassemble the contact breaker assembly to the magneto using a retaining screw having the standard type of head which provides direct contact for the carbon button in the contact breaker cover.
3. Remove the coiled wire spring from the contact breaker cover. or ANO 107.2.16.2.5.
Compliance: Before installation in an aircraft.