AD 2006-21-01 Airworthiness Directives; Boeing Model 737 Airplanes

Models named: 737-100, -200, -200C, -300, -400, -500, -600, -700, -700C, -800. Read the applicability below — it usually turns on serial or part numbers too.

This AD applies to all Boeing Model 737-100, -200, -200C, -300, -400, -500, -600, -700, -700C, -800, and -900 series airplanes; certificated in any category.

You are responsible for having the actions required by this AD performed within the compliance times specified, unless the actions have already been done. Service Bulletin References (f) The term “service bulletin,” as used in this AD, means the Accomplishment Instructions of the following service bulletins, as applicable: (1) For Boeing Model 737-100, -200, -200C, -300, -400, and -500 series airplanes: Boeing Special Attention Service Bulletin 737-27-1272, dated September 29, 2005. (2) For Boeing Model 737-600, -700, -700C, -800 and -900 series airplanes: Boeing Special Attention Service Bulletin 737-27-1273, dated September 29, 2005. Repetitive Measurements (g) Within 24 months after the date of issuance of the original standard airworthiness certificate or the date of issuance of the original export certificate of airworthiness, or 18 months after the effective date of the AD, whichever is later: Measure the freeplay of both aileron control balance tabs. Repeat the measurement thereafter at the applicable interval in paragraph (g)(1) or (g)(2) of this AD. Do all actions required by this paragraph in accordance with the applicable service bulletin. (1) For Boeing Model 737-100, -200, and -200C series airplanes: At intervals not to exceed 6,000 flight hours or 24 months, whichever occurs first. (2) For Boeing Model 737-300, -400, -500, -600, -700, -700C, -800 and -900 series airplanes: At intervals not to exceed 8,000 flight hours or 24 months, whichever occurs first. Related Investigative and Corrective Actions (h) If any measurement found in paragraph (g) of this AD is outside the acceptable limits specified in the service bulletin: Before further flight, do the applicable related investigative and corrective actions in accordance with the applicable service bulletin. Repetitive Lubrication (i) Within 9 months after the date of issuance of the original standard airworthiness certificate or the date of issuance of the original export certificate of airworthiness, or within 9 months after the effective date of this AD, whichever is later: Lubricate the aileron balance tab components specified in the applicable service bulletin. Repeat the lubrication thereafter at the applicable interval in paragraph (i)(1), (i)(2), or (i)(3) of this AD. Do all actions required by this paragraph in accordance with the applicable service bulletin. (1) For Boeing Model 737-100, -200, and -200C series airplanes: At intervals not to exceed 3,000 flight hours or 9 months, whichever occurs first. (2) For Boeing Model 737-300, -400, -500, -600, -700, -700C, -800, and -900 series airplanes, on which BMS 3-33 grease is not already in use prior to the time the lubrication task is being accomplished: At intervals not to exceed 3,000 flight hours or 9 months, whichever occurs first. (3) For Boeing Model 737-300, -400, -500, -600, -700, -700C, -800, and -900 series airplanes, on which BMS 3-33 grease is already in use prior to the time the lubrication task is being accomplished: At intervals not to exceed 4,000 flight hours or 12 months, whichever occurs first. Concurrent Repetitive Cycles (j) If a freeplay measurement required by paragraph (g) of this AD and a lubrication cycle required by paragraph (i) of this AD are due at the same time or will be accomplished during the same maintenance visit, the freeplay measurement and applicable related investigative and corrective actions must be done before the lubrication is accomplished. Alternative Methods of Compliance (AMOCs) (k)(1) The Manager, Seattle Aircraft Certification Office (ACO), FAA, has the authority to approve AMOCs for this AD, if requested in accordance with the procedures found in 14 CFR 39.19. (2) Before using any AMOC approved in accordance with § 39.19 on any airplane to which the AMOC applies, notify the appropriate principal inspector in the FAA Flight Standards Certificate Holding District Office. (3) An AMOC that provides an acceptable level of safety may be used for any repair required by this AD, if it is approved by an Authorized Representative for the Boeing Commercial Airplanes Delegation Option Authorization Organization who has been authorized by the Manager, Seattle ACO, to make those findings. For a repair method to be approved, the repair must meet the certification basis of the airplane, and the approval must specifically refer to this AD. Material Incorporated by Reference (l) You must use Boeing Special Attention Service Bulletin 737-27-1272, dated September 29, 2005; or Boeing Special Attention Service Bulletin 737-27-1273, dated September 29, 2005; as applicable; to perform the actions that are required by this AD, unless the AD specifies otherwise. The Director of the Federal Register approved the incorporation by reference of these documents in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Contact Boeing Commercial Airplanes, P.O. Box 3707, Seattle, Washington 98124-2207, for a copy of this service information. You may review copies at the Docket Management Facility, U.S. Department of Transportation, 400 Seventh Street SW., Room PL-401, Nassif Building, Washington, DC; on the Internet at http://dms.dot.gov; or at the National Archives and Records Administration (NARA). For information on the availability of this material at the NARA, call (202) 741-6030, or go to http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html . Issued in Renton, Washington, on September 28, 2006. Kalene C. Yanamura, Acting Manager, Transport Airplane Directorate, Aircraft Certification Service. [FR Doc. E6-16553 Filed 10-6-06; 8:45 am] BILLING CODE 4910-13-P

This AD results from reports of freeplay-induced vibration of the aileron balance tab. The potential for vibration of the control surface should be avoided because the point of transition from vibration to divergent flutter is unknown. We are issuing this AD to prevent excessive vibration of the airframe during flight, which could result in loss of control of the airplane.