Airworthiness Directive E6-18688
recurringAirworthiness Directives; Air Tractor, Inc. Model AT-602 Airplanes
What this AD requires
The FAA adopts a new airworthiness directive (AD) for all Air Tractor, Inc. (Air Tractor) Model AT-602 airplanes. This AD requires you to repetitively inspect (using the eddy current method) the wing center splice joint two outboard fastener holes on both of the wing main spar lower caps for fatigue cracking; repair or replace any wing main spar lower cap where fatigue cracking is found; and report any fatigue cracking found. This AD results from fatigue cracking at the wing center splice joint outboard fastener hole in one of the wing main spar lower caps. We are issuing this AD to detect and correct cracks in the wing main spar lower cap, which could result in failure of the spar cap and lead to wing separation and loss of control of the airplane.
Which aircraft AD E6-18688 applies to
applicability derived from the AD summary — confirm the model/serial from the records
Whether AD E6-18688 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.