Down to the Wire

SFAR 88: Wiring and fuel system safety

The FAA has provided some minimum airworthiness limitation items (ALI) criteria for the maintenance instructions:

  • The location of the fuel tank system components to be maintained or inspected and any access requirements
  • Any unique procedures required, such as special detailed inspections or a dual sign-off maintenance record of requirements
  • Specific task information, such as inspections defined by pictures or schematics
  • Intervals for any repetitive task
  • Methods, techniques and practices required to perform a task and the pass/fail criteria for any inspection
  • Special equipment or testapparatus required

Inspections and corrective actions are not the end of SFAR 88/EAPAS-FTS. Training and maintenance techniques also play a part in compliance. Operators may prevent adverse effects associated with wiring changes by standardizing maintenance practices through training. Training may also prevent random wire routing and wire splicing and assist with explaining the important features of fuel tank system safety.

In addition to the design changes and inspections that have been noted by OEMs and STC holders, SFAR 88 with EAPAS-FTS creates the opportunity to enhance fuel system safety through regulatory driven improvements — in plain English: airworthiness directives, ADs. Operators should be noticing the fuel system related airworthiness directives that are being published as NPRMs and final rules. These ADs include operational aspects as well as wire protection. Compliance with some of these ADs may be achieved through AMOCs (alternative means of compliance) such as ground fault interrupters (GFIs), transient suppression devices (TSD), and other circuit protective devices. Companies are working on very economical and easy to implement AMOC solutions to the ADs.

This article is intended to be a reminder that the SFAR 88/EAPAS-FTS deadline will soon arrive. The more subtle suggestion is to incorporate the instructions earlier and obtain approvals of any necessary deviations.

Photos courtesy of Butler National Corp. Butler National Corp. is a supplier that not only provides solutions, but also helps the operators with advice and cost-effectively installing the products (TSDs and GFIs). Chris Reedy is an engineer, type-rated pilot, and published writer working for Butler National Corp., a company focused on manufacturing support systems for “Classic” commercial and military aircraft with products such as the Butler National TSD for the Boeing 737 and 747 “Classic” aircraft and the Butler National GFI for Classic and New Generation models. For more information visit

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