Story ID: 
FAA Publishes Legal Interpretation of AD Rules
By: Gordon Gilbert
Caption: Agency says operators have an “ongoing obligation” to ensure that the maintenance or modification mandated by an AD is maintained.
Word Count: 206
In response to a 2011 proposed legal interpretation of FAR Part 39 AD rules, the FAA recently issued a final interpretation. The agency received numerous comments on the proposal, with most responses focusing on two specific questions: “what is the extent of an operator’s continuing obligation following the issuance of an AD?” and “what is the extent of an operator’s responsibilities when an AD requires an action that cannot be accomplished?”

The FAA interprets FAR 39.7 and 39.9 to mean that operators have an “ongoing obligation” to ensure that the maintenance or modification mandated by an AD is maintained. For changes to AD-mandated modifications and for deviations from ADs that do not have a terminating action, the operator must obtain approval for an alternative means of compliance (Amoc) with the AD.

With regard to the second question, the FAA noted that FAR 39.15 and 39.17 require ADs to apply to a specific product, “even if the product has been changed through component removal, replacement or other modification.” An operator must request Amoc approval “even if the affected component has been removed, rendering compliance with the specific requirements of the AD impossible.” The request must show that the operator’s actions eliminated the unsafe condition.