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25-27 - Development of Transport Category Airplane Electrical Wiring Interconnection Systems Instructions for Continued Airworthiness Using an Enhanced Zonal Analysis Procedure (Cancelled)

Cancellation Notes
AC 25-27A
Date Cancelled
May 04, 2007
Date Issued
November 23, 2007
Responsible Office
ANM-100,  Aircraft Certification Service, Transport Airplane Directorate

This advisory circular (AC) describes the compliance process for the “Enhanced Airworthiness Program for Airplane Systems/Fuel Tank Safety (EAPAS/FTS)” rule. That rule requires design approval holders (DAH) to develop instructions for continued airworthiness (ICA) consisting of maintenance and inspection tasks, intervals and procedures for the representative airplane’s electrical wiring interconnection system (EWIS) for each affected type design. The DAH must also review any fuel tank system ICA it has developed in compliance with Special Federal Aviation Regulation (SFAR) 88 in order to ensure compatibility with the EWIS ICA, including minimizing redundant requirements. The DAH must then submit the EWIS ICA to the FAA Oversight Office for review and approval.