2023-15-07: Horizontal Stabilizer Structure; Horizontal stabilizer, Spar/Rib; Horizontal Stabilizer Miscellaneous Structure; Vertical Stabilizer Structure

1. The authority citation for part 39 continues to read as follows: Authority: 49 U.S.C. 106(g), 40113, 44701. 2. The FAA amends § 39.13 by adding the following new airworthiness directive: 2023-15-07 Air Tractor, Inc.: Amendment 39-22519; Docket No. FAA-2023-1653; Project Identifier AD-2023-00899-A. (a) Effective Date This airworthiness directive (AD) is effective August 9, 2023. (b) Affected ADs None. (c) Applicability This AD applies to Air Tractor, Inc. Model AT-802 and AT-802A airplanes, all serial numbers, certificated in any category, that have Wipaire, Inc. Supplemental Type Certificate (STC) No. SA01795CH installed. (d) Subject Joint Aircraft System Component (JASC) Code 5510, Horizontal Stabilizer Structure; 5511 Horizontal stabilizer, Spar/Rib; 5514, Horizontal Stabilizer Miscellaneous Structure; 5530, Vertical Stabilizer Structure. (e) Unsafe Condition This AD was prompted by reports of cracks found in at least one forward horizontal stabilizer spar on 24 of the affected airplanes where the vertical finlets tie to the forward horizontal stabilizer spar. The FAA is issuing this AD to prevent structural failure of the forward horizontal stabilizer spars. The unsafe condition, if not addressed, could result in structural failure of the horizontal tail with consequent loss of control of the airplane. (f) Compliance Comply with this AD within the compliance times specified, unless already done. (g) Required Actions (1) At the compliance times in paragraphs (g)(1)(i) through (iii) of this AD, as applicable, and thereafter at intervals not to exceed 200 hours time-in-service (TIS), inspect the left and right forward horizontal stabilizer spars for cracks in accordance with Steps 1 through 9 of the Work Instructions of Wipaire, Inc. Service Letter 253, Revision B, dated July 27, 2023. (i) For STC configuration 7D1-4399-01: Within 3 days or 24 hours TIS after the effective date of this AD or before the accumulation of 200 hours TIS since installation of STC No. SA01795CH, whichever occurs later. (ii) For STC configuration 7D1-4399-02: Within 5 days or 24 hours TIS after the effective date of this AD or before the accumulation of 300 hours TIS since installation of STC No. SA01795CH, whichever occurs later. (iii) For STC configuration 7D1-4399-03: Within 15 days or 24 hours TIS after the effective date of this AD or before the accumulation of 600 hours TIS since installation of STC No. SA01795CH, whichever occurs later. (2) If any crack is found in a forward horizontal stabilizer spar during any inspection required by paragraph (g)(1) of this AD, before further flight, replace the cracked forward horizontal stabilizer spar. Replacement of the cracked forward horizontal stabilizer spar starts the initial and repetitive inspections over. (3) Within 10 days after each inspection required by paragraph (g)(1) of this AD or within 10 days after the effective date of this AD, whichever occur later, report the following to the FAA at the address in paragraph (j)(1) of this AD. Report this information regardless of whether cracks are found. (i) Model, engine configuration (with horsepower limits), and propeller type; (ii) Serial number and N number; (iii) Total hours TIS on airframe; (iv) Total hours TIS operated with floats, if known; (v) STC configuration and total hours with STC installed; (vi) Crack location (right or left, upper/lower caps inboard/outboard hole); (vii) Crack size; (viii) Photos of cracks found, if available; and (ix) Any additional operator/mechanic comments (h) Credit for Previous Actions You may take credit for the initial inspection required by paragraph (g)(1) of this AD if, before the effective date of this AD, you complied with Wipaire, Inc. Service Letter 253, Revision A, dated April 5, 2023. (i) Alternative Methods of Compliance (AMOCs) (1) The Manager, Central Certification Branch, FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. In accordance with 14 CFR 39.19, send your request to your principal inspector or local Flight Standards District Office, as appropriate. If sending information directly to the manager of the Certification Branch, send it to the attention of the person identified in paragraph (j)(1) of this AD. (2) Before using any approved AMOC, notify your appropriate principal inspector, or lacking a principal inspector, the manager of the local flight standards district office/certificate holding district office. (j) Related Information (1) For more information about this AD, contact Tim Eichor, Aviation Safety Engineer, Central Certification Branch, FAA, 1801 S Airport Road, Wichita, KS 67209; phone: (847) 294-7141; email: tim.d.eichor@faa.gov. (2) Service information identified in this AD that is not incorporated by reference is available at the addresses specified in paragraphs (k)(3) and (4) of this AD. (k) Material Incorporated by Reference (1) The Director of the Federal Register approved the incorporation by reference (IBR) of the service information listed in this paragraph under 5 U.S.C. 552(a) and 1 CFR part 51. (2) You must use this service information as applicable to do the actions required by this AD, unless the AD specifies otherwise. (i) Wipaire, Inc. Service Letter 253, Revision B, dated July 27, 2023. (ii) [Reserved] (3) For service information identified in this AD, contact Wipaire, Inc., 1700 Henry Ave, Fleming Field (KSGS), South St. Paul, MN 55075; phone: (651) 451-1205; email: customerservice@wipaire.com; website: wipaire.com. (4) You may view this service information at the FAA, Airworthiness Products Section, Operational Safety Branch, 901 Locust, Kansas City, MO 64106. For information on the availability of this material at the FAA, call (817) 222-5110. (5) You may view this service information that is incorporated by reference at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, email: fr.inspection@nara.gov, or go to: www.archives.gov/federal-register/cfr/ibr-locations.html. Issued on July 28, 2023. Ross Landes, Deputy Director for Regulatory Operations, Compliance & Airworthiness Division, Aircraft Certification Service. [FR Doc. 2023-16964 Filed 8-7-23; 11:15 am]BILLING CODE 4910-13-P