AD 2006-08-08 R1
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Air Tractor Inc. | AT-400 | Airworthiness Directives; Air Tractor, Inc. Models AT-400, AT- 401, AT-401B, AT-402, AT-402A, and AT-402B Airplanes |
| aircraft | Air Tractor Inc. | AT-401 | Airworthiness Directives; Air Tractor, Inc. Models AT-400, AT- 401, AT-401B, AT-402, AT-402A, and AT-402B Airplanes |
| aircraft | Air Tractor Inc. | AT-401B | Airworthiness Directives; Air Tractor, Inc. Models AT-400, AT- 401, AT-401B, AT-402, AT-402A, and AT-402B Airplanes |
| aircraft | Air Tractor Inc. | AT-402 | Airworthiness Directives; Air Tractor, Inc. Models AT-400, AT- 401, AT-401B, AT-402, AT-402A, and AT-402B Airplanes |
| aircraft | Air Tractor Inc. | AT-402A | Airworthiness Directives; Air Tractor, Inc. Models AT-400, AT- 401, AT-401B, AT-402, AT-402A, and AT-402B Airplanes |
| aircraft | Air Tractor Inc. | AT-402B | Airworthiness Directives; Air Tractor, Inc. Models AT-400, AT- 401, AT-401B, AT-402, AT-402A, and AT-402B Airplanes |
Unsafe Condition
Fatigue cracking of the wing lower spar cap could occur, which could result in reduced structural integrity of the wing and possible wing failure.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Inspect the wing lower spar cap for fatigue cracking, perform repairs if necessary, and repeat inspections at specified intervals.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
within 120 flight hours after August 8, 2006, or at the next annual inspection, whichever occurs first.
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
Air Tractor, Inc. Models AT-400, AT-401, AT-401B, AT-402, AT-402A, and AT-402B airplanes.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Wing lower spar cap
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - 2006-08-08R1.pdf Copy URL Document Versions Feedback DetailsAttachments/Public Comments AD Number: 2006-08-08 R1 Document Type: AD Final Rules Docket Number: FAA-2006-23646 Subject Heading: Airworthiness Directives; Air Tractor, Inc. Models AT-400, AT- 401, AT-401B, AT-402, AT-402A, and AT...Show more Subject: Wing lower spar cap Status: Current Citation: Federal Register: March 31, 2009 Citation Publish Date: 03/31/2009 Effective Date: 05/05/2009 Make: Air Tractor Inc. Model: AT-400 | AT-401 | AT-401B | AT-402 | AT-402A | AT-402B Product Type: Aircraft Product Subtype: Small Airplane Affected AD: Superseded AD: 2006-08-08 Affected By: Superseded By: Service/Office: AIR-700: Compliance & Airworthiness Division Office of Primary Responsibility: AIR-720: Operational Safety Branch CFR Part Reference: Part 39 Comments: auto page-actual page-fit page-width 125%
Document Text
Show stored source text (verify against official source)
AD Final Rules - 2006-08-08R1.pdf Copy URL Document Versions Feedback DetailsAttachments/Public Comments AD Number: 2006-08-08 R1 Document Type: AD Final Rules Docket Number: FAA-2006-23646 Subject Heading: Airworthiness Directives; Air Tractor, Inc. Models AT-400, AT- 401, AT-401B, AT-402, AT-402A, and AT...Show more Subject: Wing lower spar cap Status: Current Citation: Federal Register: March 31, 2009 Citation Publish Date: 03/31/2009 Effective Date: 05/05/2009 Make: Air Tractor Inc. Model: AT-400 | AT-401 | AT-401B | AT-402 | AT-402A | AT-402B Product Type: Aircraft Product Subtype: Small Airplane Affected AD: Superseded AD: 2006-08-08 Affected By: Superseded By: Service/Office: AIR-700: Compliance & Airworthiness Division Office of Primary Responsibility: AIR-720: Operational Safety Branch CFR Part Reference: Part 39 Comments: auto page-actual page-fit page-width 125%
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
This site is not affiliated with or endorsed by the FAA. Always verify with official sources.
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