Airworthiness Directive 2012-08-17
one-timeAirworthiness Directives; The Boeing Company Airplanes
What this AD requires
We are adopting a new airworthiness directive (AD) for certain The Boeing Company Model 737-100, -200, -200C, -300, -400, and -500 series airplanes equipped with analog transient suppression devices (ATSDs) installed in accordance with Supplemental Type Certificate ST00146BO. This AD was prompted by multiple reports of corrosion on ATSDs. This AD requires revising the maintenance program to incorporate certain limitations. We are issuing this AD to detect and correct corrosion on ATSDs, which could result in the loss of high voltage transient protection (e.g., lightning protection) in the fuel tanks and consequent fuel tank explosion and loss of the airplane.
Which aircraft AD 2012-08-17 applies to
Applies only to airplanes with an original airworthiness certificate or original export certificate of airworthiness issued before September 26, 2011, equipped with analog transient suppression devices (ATSDs) installed in accordance with Supplemental Type Certificate ST00146BO.
Whether AD 2012-08-17 actually applies to your aircraft (by serial and installed parts) and whether it’s already complied with comes from that aircraft’s records.
How AD compliance is recorded
A valid compliance record (14 CFR 43.9) states:
Tailplate reads a tail number’s logbooks and matches every applicable AD — including this one — to its compliance evidence, with recurring next-due dates computed.
Look up a tail number →Read the full directive (Federal Register)Applicability is derived from the FAA directive corpus and is advisory, not a legal airworthiness determination. Compliance is established only from an aircraft’s actual records.