AD 2001-18-11

This amendment adopts a new airworthiness directive (AD) that is applicable to certain McDonnell Douglas Model 717 series airplanes. This action requires a one-time inspection of the support seal tubes of the rudder trim and load-feel actuator assembly of the rudder trim control system, located in the aft accessory compartment, for proper clearance between the actuator support seal tube and spring capsule assembly, and applicable follow-on/corrective actions. This action is necessary to detect and correct the accumulation of moisture in the rudder trim and load-feel actuator of the rudder trim control system. Such moisture could freeze and cause stiff operation, binding, or jamming of the rudder trim control system and consequent jamming of the rudder; and adversely affect directional control of an airplane.

Final rule; request for comments

2001-18-11 McDonnell Douglas: Amendment 39-12437. Docket 2001-NM-230-AD. \n\n\tApplicability: Model 717 series airplanes, as listed in Boeing Alert Service Bulletin 717-27A0016, including Appendix, dated April 9, 2001; certificated in any category. \n\n\tNote 1: This AD applies to each airplane identified in the preceding applicability provision, regardless of whether it has been modified, altered, or repaired in the area subject to the requirements of this AD. For airplanes that have been modified, altered, or repaired so that the performance of the requirements of this AD is affected, the owner/operator must request approval for an alternative method of compliance in accordance with paragraph (d) of this AD. The request should include an assessment of the effect of the modification, alteration, or repair on the unsafe condition addressed by this AD; and, if the unsafe condition has not been eliminated, the request should include specific proposed actions to address it. \n\n\tCompliance: Required as indicated, unless accomplished previously. \n\n\tTo detect and correct the accumulation of moisture in the rudder trim and load-feel actuator of the rudder trim control system, which could freeze and cause stiff operation, binding, or jamming of the rudder trim control system and consequent jamming of the rudder; and adversely affect directional control of an airplane; accomplish the following: \n\nDetailed Visual Inspection \n\n\t(a) Within 60 days after the effective date of this AD, do a one-time detailed visual inspection of the support seal tube of the rudder trim and load-feel actuator assembly, located in the aft accessory compartment, for proper clearance between the actuator support seal tube and spring capsule assembly, per paragraph 3.B. of the Accomplishment Instructions of Boeing Alert Service Bulletin 717-27A0016, including Appendix, dated April 9, 2001; and, before further flight, accomplish the actions specified in paragraph (a)(1) or (a)(2) of this AD, as applicable. \n\n\tNote 2: For the purposes of this AD, a detailed visual inspection is defined as: "An intensive visual examination of a specific structural area, system, installation, or assembly to detect damage, failure, or irregularity. Available lighting is normally supplemented with a direct source of good lighting at intensity deemed appropriate by the inspector. Inspection aids such as mirror, magnifying lenses, etc., may be used. Surface cleaning and elaborate access procedures may be required." \n\n\tNote 3: The Boeing service bulletin refers to BFGoodrich Aerospace Service Bulletin DL4528M1-27-20, dated April 3, 2001, as an additional source of service information for accomplishment of the one-time detailed visual inspection and follow-on/corrective actions. \n\nFollow-on/Corrective Actions \n\nCondition 1: For a 5-inch Support Seal Tube \n\n\t\t(1) Reidentify the rudder trim and load-feel actuator assembly, and apply a nylon or polyurethane clear coating, per Condition 1, paragraphs 1 through 3, paragraph 3.B. of the Accomplishment Instructions of the service bulletin. Where there are differences between the AD and the service information, the AD prevails. \n\nCondition 2: For a 6-inch Support Seal Tube \n\n\t\t(2) Modify (including removing sealant from around the screw heads and flange of the support seal tube; removing safety wire from screws; removing the support seal tube; cleaning any excess sealant compound from the support seal tube, cover, and front cap; applying sealing compound to the support tube at certain locations; installing and securing a new support seal tube, using six screws having a specified torque value and securing them with safety wire; reidentifying the actuator identification plate; and applying a clear coating to the flange of the support seal tube) and reidentify the rudder trim and load-feel actuator assembly; and install the modified and reidentified actuator assembly; per Condition 2, paragraphs 1 through 14, paragraph 3.B. of the Accomplishment Instructions of the service bulletin. \n\n\tNote 4: Although the BFGoodrich service bulletin specifies that the action for Condition 1 is for a 5.25-inch support seal tube and Condition 2 is for a 6.25-inch support seal tube, this AD specifies 5 inches and 6 inches respectively, as cited in the Boeing service bulletin. \n\nReporting Requirement \n\n\t(b) Within 10 days after accomplishing the one-time inspection required by paragraph (a) of this AD, submit a report of the inspection results (both positive and negative findings) to the Manager, Los Angeles Aircraft Certification Office (ACO), FAA, or to Boeing, per the Appendix of Boeing Alert Service Bulletin 717-27A0016, dated April 9, 2001. The report must include the part number and serial number of the rudder trim load feel actuator, date of inspection, fuselage number, and number of flight hours or flight cycles on the airplane. The report also must include whether the support seal tube found installed on the airplane during the detailed visual inspection required by paragraph (a) of this AD is 5 inches or 6 inches. Information collection requirements contained in this regulation have been approved by the Office of Management and Budget (OMP) under the provisions of the Paperwork Reduction Act of 1980 (44 U.S.C. 3501 et seq.) and have been assigned OMB Control Number 2120-0056. \n\nSpares \n\n\t(c) As of the effective date of this AD, no person shall install on any airplane, a support seal tube, part number (P/N) A9543, Revision A, on a rudder trim and load-feel actuator, P/N DL4528M1MOD5 or P/N DL4528M1MOD6. \n\nAlternative Methods of Compliance \n\n\t(d) An alternative method of compliance or adjustment of the compliance time that provides an acceptable level of safety may be used if approved by the Manager, Los Angeles Aircraft Certification Office (ACO), FAA. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, Los Angeles ACO. \n\n\tNote 5: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Los Angeles ACO. \n\nSpecial Flight Permits \n\n\t(e) Special flight permits may be issued in accordance with sections 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 21.197 and 21.199) to operate the airplane to a location where the requirements of this AD can be accomplished. \n\nIncorporation by Reference \n\n\t(f) The actions shall be done in accordance with Boeing Alert Service Bulletin 717-27A0016, including Appendix, dated April 9, 2001. This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be obtained from Boeing Commercial Aircraft Group, Long Beach Division, 3855 Lakewood Boulevard, Long Beach, California 90846, Attention: Data and Service Management, Dept. C1-L5A (D800-0024). Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the FAA, Los Angeles Aircraft Certification Office, 3960 Paramount Boulevard, Lakewood, California; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC. \n\nEffective Date \n\n\t(g) This amendment becomes effective on October 1, 2001.

The FAA has received several reports of in-flight binding and/or stiff operation of the rudder trim control system on McDonnell Douglas Model 717 series airplanes. Subsequent investigation indicates that approximately 60 rudder trim and load-feel actuators were manufactured with insufficient clearance between the actuator support seal tube and spring capsule assembly, and these actuators were installed on Model 717 series airplanes. Moisture condensing in the area of those components could freeze and cause stiff operation, binding, or jamming of the rudder trim control system. Such conditions could result in consequent jamming of the rudder and adversely affect directional control of an airplane. \n\nExplanation of Relevant Service Information \n\n\tThe FAA has reviewed and approved Boeing Alert Service Bulletin 717-27A0016, including Appendix, dated April 9, 2001, which describes procedures for a one-time inspection of the support seal tubes of the rudder trim and load-feel actuator assembly of the rudder trim control system, located in the aft accessory compartment, for proper clearance between the actuator support seal tube and spring capsule assembly, and applicable follow-on/corrective actions. The Boeing service bulletin refers to BFGoodrich Aerospace Service Bulletin DL4528M1-27-20, dated April 3, 2001, as an additional source of service information. The inspection and follow-on/corrective actions include the following procedures: \n\nCondition 1: For a 5-inch support seal tube, as specified in the Boeing service bulletin, reidentify the rudder trim and load-feel actuator assembly, and apply a nylon or polyurethane clear coating. \n\nCondition 2: For a 6-inch support seal tube, as specified in the Boeing service bulletin, modify and reidentify the actuator assembly, and install the modified and reidentified actuator assembly. Modification action includes removing sealant from around the screw heads and flange of the support seal tube; removing safety wire from screws; removing the support seal tube; cleaning any excess sealant compound from the support seal tube, cover, and front cap; applying sealing compound to the support tube at certain locations; installing and securing a new support seal tube, using six screws having a specified torque value and securing them with safety wire; reidentifying the actuator identification plate; and applying a clear coating to the flange of the support seal tube. \n\nExplanation of the Requirements of the Rule \n\n\tSince an unsafe condition has been identified that is likely to exist or develop on other McDonnell Douglas Model 717 series airplanes of the same type design, this AD is being issued to detect and correct the accumulation of moisture in the rudder trim and load-feel actuator of the rudder trim control system. Such moisture could freeze and result in stiff operation, binding, or jamming of the rudder trim control system and consequent jamming of the rudder; and adversely affect directional control of an airplane. \n\n\tThis AD requires accomplishment of the actions specified by the previously referenced Boeing service bulletin, except as discussed below. \n\nDifferences Between the Service Information and This AD \n\n\tOperators should note that the BFGoodrich Aerospace service bulletin, which is referenced by the Boeing service bulletin as an additional source of information, specifies the application of a nylon or polyurethane clear coating \n"or equivalent." However, the FAA has determined that it is necessary to specify the use of a nylon or polyurethane clear coating in paragraph (a)(1) of this AD. \n\n\tOperators also should note that the reporting requirement in paragraph (b) of this AD also includes an additional requirement to identify whether a 5-inch or a 6-inch support seal tube is found installed on the airplane during the inspection required by paragraph (a) of this AD. \n\nInterim Action \n\n\tThis is considered to be interim action until final action is identified, at which time the FAA may consider further rulemaking. \n\nDetermination of Rule's Effective Date \n\n\tSince a situation exists that requires the immediate adoption of this regulation, it is found that notice and opportunity for prior public comment hereon are impracticable, and that good cause exists for making this amendment effective in less than 30 days. \n\nComments Invited \n\n\tAlthough this action is in the form of a final rule that involves requirements affecting flight safety and, thus, was not preceded by notice and an opportunity for public comment, comments are invited on this rule. Interested persons are invited to comment on this rule by submitting such written data, views, or arguments as they may desire. Communications shall identify the Rules Docket number and be submitted in triplicate to the address specified under the caption ADDRESSES. All communications received on or before the closing date for comments will be considered, and thisrule may be amended in light of the comments received. Factual information that supports the commenter's ideas and suggestions is extremely helpful in evaluating the effectiveness of the AD action and determining whether additional rulemaking action would be needed. \n\n\tSubmit comments using the following format: \n\nOrganize comments issue-by-issue. For example, discuss a request to change the compliance time and a request to change the service bulletin reference as two separate issues. \n\nFor each issue, state what specific change to the AD is being requested. \n\nInclude justification (e.g., reasons or data) for each request. \n\n\tComments are specifically invited on the overall regulatory, economic, environmental, and energy aspects of the rule that might suggest a need to modify the rule. All comments submitted will be available, both before and after the closing date for comments, in the Rules Docket for examination by interested persons. A report that summarizes each FAA-public contact concerned with the substance of this AD will be filed in the Rules Docket. \n\n\tCommenters wishing the FAA to acknowledge receipt of their comments submitted in response to this rule must submit a self-addressed, stamped postcard on which the following statement is made: "Comments to Docket Number 2001-NM-230-AD." The postcard will be date stamped and returned to the commenter. \n\nRegulatory Impact \n\n\tThe regulations adopted herein will not have a substantial direct effect on the States, on the relationship between the national Government and the States, or on the distribution of power and responsibilities among the various levels of government. Therefore, it is determined that this final rule does not have federalism implications under Executive Order 13132. \n\n\tThe FAA has determined that this regulation is an emergency regulation that must be issued immediately to correct an unsafe condition in aircraft, and that it is not a "significant regulatory action" under Executive Order 12866. It has been determined further that this action involves an emergency regulation under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979). If it is determined that this emergency regulation otherwise would be significant under DOT Regulatory Policies and Procedures, a final regulatory evaluation will be prepared and placed in the Rules Docket. A copy of it, if filed, may be obtained from the Rules Docket at the location provided under the caption ADDRESSES. \n\nList of Subjects in 14 CFR Part 39 \n\n\tAir transportation, Aircraft, Aviation safety, Incorporation by reference, Safety. \n\nAdoption of the Amendment \n\n\tAccordingly, pursuant to the authority delegated to me by the Administrator, the Federal Aviation Administration amends part 39 of the Federal Aviation Regulations (14 CFR part 39) as follows: \n\nPART 39--AIRWORTHINESS DIRECTIVES \n\n\t1. The authority citation for part 39 continues to read as follows: \n\n\tAuthority: 49 U.S.C. 106(g),40113, 44701. \n\nSec. 39.13 (Amended) \n\n\t2. Section 39.13 is amended by adding the following new airworthiness directive: