Skip to Content


Proposed Advisory Circular 120-XX, Damage Tolerance Inspections for Repairs

Document Details

Information about this document as published in the Federal Register.

Published Document

This document has been published in the Federal Register. Use the PDF linked in the document sidebar for the official electronic format.

Start Preamble


Federal Aviation Administration, DOT.


Notice of availability of proposed Advisory Circular (AC) 120-XX, and request for comments.


This notice announces the availability of and requests comments on a proposed advisory circular (AC) which sets forth an acceptable means, but not the only means, of demonstrating compliance with the provisions of the airworthiness standards for transport category airplanes related to damage tolerance inspections for repairs. This proposed AC complements revisions to the airworthiness standards that are being proposed by a separate notice. This notice is necessary to give all interested persons an opportunity to present their views on the proposed AC.


Comments must be received on or before June 20, 2006.


Send all comments on this proposed AC to: Federal Aviation Administration, Attention: Greg Schneider, Airframe/Cabin Safety Branch, ANM-115, FAA, Transport Airplane Directorate, Aircraft Certification Service, 1601 Lind Avenue SW., Renton, WA 98055-4056. Comments may be inspected at the above address between 7:30 a.m. and 4 p.m. weekdays, except Federal holidays.

Start Further Info


Kenna Sinclair, Transport Standards Staff, at the address above, telephone (425) 227-1556.

End Further Info End Preamble Start Supplemental Information


Comments Invited

Interested persons are invited to comment on the proposed AC by submitting such written data, views, or arguments, as they may desire. Commenters should identify AC 120-XX and submit comments, in duplicate, to the address specified above. All communications received on or before the closing date for comments will be considered by the Transport Standards Staff before issuing the final AC. The proposed AC can be found and downloaded from the Internet at​aircraft/​draft_​docs. A paper copy of the proposed AC may be obtained by contacting the person named above under the caption FOR FURTHER INFORMATION CONTACT.


This proposed AC would provide guidance material for design approval holders and operators for developing and incorporating damage tolerance inspections and procedures (DTIP). The proposed AC would support compliance with Title 14 Code of Federal Regulations (14 CFR) 121.370a and 14 CFR 129.16, the Aging Airplane Safety Final Rule (AASFR), with respect to repairs. For compliance, operators would need to demonstrate that new and existing repairs would have an evaluation and DTIP or other procedures implemented, if needed. The proposed AC would be applicable to repairs that affect fatigue critical structure. The AASFR also requires operators to incorporate DTIP for alterations that affect fatigue critical structure. The Aviation Rulemaking Advisory Committee (ARAC) Airworthiness Assurance Working Group (AAWG) is currently developing guidance for developing DTIP for such alterations. It is anticipated that this guidance will be incorporated into this AC. Upon completion of this work, the Start Printed Page 20751FAA plans to issue a revision to this AC that will include guidance applicable to both repairs and alterations.

The proposed AC supports compliance with the part 25 revisions proposed in Notice No. 05-11 entitled “Damage Tolerance Data for Repairs and Alterations” published in this same edition of the Federal Register.

Start Signature

Issued in Washington, DC, on April 13, 2006.

James J. Ballough,

Director, Flight Standards Service, Aviation Safety.

Dorenda D. Baker,

Acting Director, Aircraft Certification Service, Aviation Safety.

End Signature End Supplemental Information

[FR Doc. 06-3757 Filed 4-20-06; 8:45 am]