2004-15-15: Aft Fuselage Upper Longeron

2004-15-15 Air Tractor, Inc.: Amendment 39-13749; Docket No. 2004-CE-05-AD; Supersedes AD 2002-19-10; Amendment 39-12890. When Does This AD Become Effective? (a) This AD becomes effective on September 7, 2004. What Other ADs Are Affected by This Action? (b) This AD supersedes AD 2002-19-10. What Airplanes Are Affected by This AD? (c) This AD affects the following airplane models and serial numbers that are certificated in any category: Model Serial Nos. AT-401, AT-401B, AT-402, AT-402A, and AT-402B. 0716 through 1144 AT-501, AT-502, AT-502A, AT-502B, and AT-503A. 0037 through 0658 AT-602 0337 through 0664 AT-802 and AT-802A 0001 through 0139 What Is the Unsafe Condition Presented in This AD? (d) This AD is the result of reports of cracks in the aft fuselage upper longeron, originally detected as excessive movement in the empennage due to the loss of fuselage torsional rigidity. The actions specified in this AD are intended to detect and correct cracks in the upper aft longeron, which could cause the fuselage to fail. Such failure could result in loss of control of the airplane. What Must I Do To Address This Problem? (e) To address this problem, you must inspect the upper longeron and upper diagonal tube (as applicable) on the left hand side of the fuselage frame just forward of the vertical fin front spar attachment for cracks at the times specified below. You must also replace and modify any cracked upper and diagonal longerons (as applicable) found during any inspection required by this AD before further flight after the inspection in which cracks are found. Affected models and serial nos. Inspection compliance times Procedures (1) AT-401, AT-401B, serial numbers (S/Ns) 0716 through 1144. Initially inspect upon the accumulation of 1,250 total hours time-in-service (TIS) or within the next 100 hours TIS after September 7, 2004 (the effective date of this AD), whichever occurs later. Repetitively inspect thereafter at intervals not to exceed 100 hours TIS until the upper and diagonal longerons are replaced and modified. Replacing and modifying the upper and diagonal longerons is the terminating action for the repetitive inspection requirement in this AD. Inspect following Snow Engineering Co. Service Letter #218A, dated November 10, 2003, as specified in Snow Engineering Co. Service Letter #195, reissued November 10, 2003. Replace and modify following Snow Engineering Co. Service Letter #218B, dated November 10, 2003. (2) AT-402, AT-402A, and AT-402B, S/Ns 0716 through 1144. Initially inspect upon the accumulation of 1,250 total hours TIS or within the next 100 hours TIS after the last inspection required by AD 2002-19-10, whichever occurs later. Repetitively inspect thereafter at intervals not to exceed 100 hours TIS until the upper and diagonal longerons are replaced and modified. Replacing and modifying the upper and diagonal longerons is the terminating action for therepetitive inspection requirement in this AD. Inspect following Snow Engineering Co. Service Letter #218A, dated November 10, 2003, as specified in Snow Engineering Co. Service Letter #195, reissued November 10, 2003. Replace and modify following Snow Engineering Co. Service Letter #218B, dated November 10, 2003. (3) AT-501, AT-502, AT -502B, and AT-503A, S/Ns 0037 through 0658. Initially inspect upon the accumulation of 4,800 total hours TIS or within the next 100 hours TIS after September 7, 2004 (the effective date of this AD), whichever occurs later. Repetitively inspect thereafter at intervals not to exceed 100 hours TIS until the upper longeron is replaced and modified. Replacing and modifying the upper longeron is the terminating action for the repetitive inspection requirement in this AD. Inspect following Snow Engineering Co. Service Letter #195B, dated November 10, 2003, as specified in Snow Engineering Co. Service Letter #195, reissued November 10, 2003. Replace and modify following Snow Engineering Co. Service Letter #195A, revised November 10, 2003. (4)AT-502A, S/Ns 0037 through 0658 Initially inspect upon the accumulation of 2,800 total hours TIS or within the next 100 hours TIS after September 7, 2004 (the effective date of this AD), whichever occurs later. Repetitively inspect thereafter at intervals not to exceed 100 hours TIS until the upper longeron is replaced and modified. Replacing and modifying the upper longeron is the terminating action for the repetitive inspection requirement in this AD. Inspect following Snow Engineering Co. Service Letter #195B, dated November 10, 2003, as specified in Snow Engineering Co. Service Letter #195, reissued November 10, 2003. Replace and modify following Snow Engineering Co. Service Letter #195A, revised November 10, 2003. (5) AT-602, S/Ns 0337 through 0661 Initially inspect upon the accumulation of 700 total hours TIS or within the next 100 hours TIS after the last inspection required by AD 2002-19-10, whichever occurs later. Repetitively inspect thereafter at intervals not to exceed 100 hours TIS until the upper longeron is replaced and modified. Replacing and modifying the upper longeron is the terminating action for the repetitive inspection requirement in this AD. Inspect following Snow Engineering Co. Service Letter #213A, dated November 10, 2003, as specified in Snow Engineering Co. Service Letter #195, reissued November 10, 2003. Replace and modify following Snow Engineering Co. Service Letter #213B, revised November 10, 2003. (6) AT-602, S/Ns 0662 through 0664 Initially inspect upon the accumulation of 1,750 total hours TIS or within the next 100 hours TIS after the last inspection required by AD 2002-19-10, whichever occurs later. Repetitively inspect thereafter at intervals not to exceed 100 hours TIS until the upper longeron is replaced and modified. Replacing and modifying the upper longeron is the terminating action for the repetitive inspection requirement in this AD. Inspect following Snow Engineering Co. Service Letter #213A, dated November 10, 2003, as specified in Snow Engineering Co. Service Letter #195, reissued November 10, 2003. Replace and modify following Snow Engineering Co. Service Letter #213B, revised November 10, 2003. (7) AT-802 and AT-802A, S/Ns 0001 through 0004 and 0012 through 0118. Initially inspect upon the accumulation of 250 total hours TIS or within the next 100 hours TIS after the last inspection required by AD 2002-19-10, whichever occurs later. Repetitively inspect thereafter at intervals not to exceed 100 hours TIS until the upper longeron is replaced and modified. Replacing and modifying the upper longeron is the terminating action for the repetitive inspection requirement in this AD. Inspect following Snow Engineering Co. Service Letter #217A, dated November 10, 2003, as specified in Snow Engineering Co. Service Letter #195, reissued November 10, 2003. Replace and modify following Snow Engineering Co. Service Letter #217B, revised November 10, 2003. (8) AT-802 and AT-802A, S/Ns 0005 through 0011. Initially inspect upon the accumulation of 900 total hours TIS or within the next 100 hours TIS after the last inspection required by AD 2002-19-10, whichever occurs later. Repetitively inspect thereafter at intervals not to exceed 100 hours TIS until the upper longeron is replaced and modified. Replacing and modifying the upper longeron is the terminating action for the repetitive inspection requirement in this AD. Inspect following Snow Engineering Co. Service Letter #217A, dated November 10, 2003, as specified in Snow Engineering Co. Service Letter #195, reissued November 10, 2003. Replace and modify following Snow Engineering Co. Service Letter #217B, revised November 10, 2003. (9) AT-802 and AT-802A, S/Ns 0119 through 0139. Initially inspect upon the accumulation of 1,750 total hours TIS or within the next 100 hours TIS after the last inspection required by AD 2002-19-10, whichever occurs later. Repetitively inspect thereafter at intervals not to exceed 100 hours TIS until the upper longeron is replaced and modified. Replacing and modifying the upper longeron is the terminating action for the repetitive inspection requirement in this AD. Inspect following Snow Engineering Co. Service Letter #217A, dated November 10, 2003, as specified in Snow Engineering Co. Service Letter #195, reissued November 10, 2003. Replace and modify following Snow Engineering Co. Service Letter #217B, revised November 10, 2003. (f) You may replace and modify the upper and diagonal longeron (as applicable) at any time as a terminating action for the repetitive inspection requirement in this AD. However, you must replace and modify the upper and diagonal longeron (as applicable) before further flight after any inspection in which cracks are found. May I Request an Alternative Method of Compliance? (g) You may request a different method of compliance or a different compliance time for this AD by following the procedures in 14 CFR 39.19. Unless FAA authorizes otherwise, send your request to your principal inspector. The principal inspector may add comments and will send your request to the Manager, Fort Worth Aircraft Certification Office (ACO), FAA. For information on any already approved alternative methods of compliance, contact Andrew D. McAnaul, Aerospace Engineer, FAA, Fort Worth ACO, 2601 Meacham Boulevard, Fort Worth, Texas 76193-0150. Current duty station: San Antonio Manufacturing Inspection District Office (MIDO), 10100 Reunion Place, Suite 650, San Antonio, Texas 78216; telephone: (210) 308-3365; facsimile: (210) 308-3370. Does This AD Incorporate Any Material by Reference? (h) You must do the actions required by this AD following the instructions in Snow Engineering Co. Service Letter 195, reissued November 10, 2003; Snow Engineering Co. Service Letter 195A, revised November 10, 2003; Snow Engineering Co. Service Letter 195B, dated November 10, 2003; Snow Engineering Co. Service Letter 213A, dated November 10, 2003; Snow Engineering Co. Service Letter 213B, revised November 10, 2003; Snow Engineering Co. Service Letter 217A, dated November 10, 2003; Snow Engineering Co. Service Letter 217B, revised November 10, 2003; Snow Engineering Co. Service Letter 218A, dated November 10, 2003; and Snow Engineering Co. Service Letter 218B, dated November 10, 2003. The Director of the Federal Register approved the incorporation by reference of this service bulletin in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. You may get a copy from Air Tractor, Incorporated, P.O. Box 485, Olney, Texas 76374. You may review copies at FAA, Central Region, Office of the Regional Counsel, 901 Locust, Room 506, Kansas City, Missouri 64106; or at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, call (202) 741-6030, or go to: http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html.