AD 2000-20-16

This amendment adopts a new airworthiness directive (AD) that is applicable to certain Boeing Model 757-200 series airplanes. This action requires repetitive inspections of the cargo loader system in the forward and aft cargo compartments to detect discrepancies, and corrective actions, if necessary. This action is necessary to detect and correct such discrepancies, which could result in reduced structural integrity of the fuselage and consequent cabin depressurization.

Final rule; request for comments

2000-20-16 BOEING: Amendment 39-11927. Docket 2000-NM-286-AD. \n\n\tApplicability: Model 757-200 series airplanes, certificated in any category, having Air Cargo Equipment cargo loader systems. \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 (c) 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\tTo detect and correct discrepancies of the cargo loader system in the forward and aft cargo compartments, which could result in reduced structural integrity of the fuselage and consequent cabin depressurization, accomplish the following: \n\nRepetitive Inspections \n\t(a) Within 60 days or 300 flight cycles after the effective date of this AD, whichever occurs first: Perform a detailed visual inspection of the cargo loader system in the forward and aft cargo compartments to detect discrepancies (i.e., improper operation, wear damage of the fiberglass pan and fuselage frames), in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 757-25A0233, dated August 10, 2000. If no discrepancies are detected, or the cargo loader system is reactivated after repair of damage, repeat the inspection thereafter at intervals not to exceed 300 flight cycles. \n\n\tNote 2: For the purposes of this AD, a detailed visual inspection is defined as: "An intensivevisual 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\nCorrective Actions \n\t(b) If any discrepancies (i.e., improper operation, wear damage of the fiberglass pan or fuselage frames), are detected during any inspection required by paragraph (a) of this AD, before further flight: Repair the discrepancies and deactivate the cargo loader system in accordance with Boeing Alert Service Bulletin 757-25A0233, dated August 10, 2000. \n\nFurther, if the damage to the fuselage frame(s) is greater than the limits shown in the 757 Structural Repair Manual, accomplish the repair in accordance with a method approved by the Manager, Seattle Aircraft Certification Office (ACO), FAA. Reactivate the cargo loader system only in accordance with a method approved by the Manager, Seattle ACO. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, Seattle ACO. \n\nAlternative Methods of Compliance \n\t(c) 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, Seattle ACO. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, Seattle ACO. \n\n\tNote 3: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Seattle ACO. \n\nSpecial Flight Permits \n\t(d) Special flight permits may be issued in accordance with sections 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR21.197 and 21.199) to operate the airplane to a location where the requirements of this AD can be accomplished. \n\nIncorporation by Reference \n\t(e) Except as provided by paragraph (b) of this AD, the actions shall be done in accordance with Boeing Alert Service Bulletin 757-25A0233, dated August 10, 2000. 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 Airplane Group, P.O. Box 3707, Seattle, Washington 98124-2207. Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC. \n\nEffective Date \n\t(f) This amendment becomes effective on October 26, 2000.

The FAA has received reports indicating that, on certain Boeing Model 757-200 series airplanes, damage has been detected to the fiberglass pan and fuselage frames located in the forward and aft cargo compartments. This damage has been attributed to incorrect operation of the cargo loader system and subsequent wear damage completely through the fiberglass pan, and in some cases, to the adjacent fuselage frames. This condition, if not corrected, could result in reduced structural integrity of the airplane fuselage and consequent cabin depressurization. \n\nExplanation of Relevant Service Information \n\tThe FAA has reviewed and approved Boeing Alert Service Bulletin 757-25A0233, dated August 10, 2000, which describes procedures for repetitive inspections of the cargo loader system in the forward and aft cargo compartments to detect discrepancies (i.e., improper operation, wear damage of the fiberglass pan and fuselage frames), and corrective actions, if necessary. \n\tThe corrective actions include procedures for repair of the cargo loader system if incorrectly installed or deactivation of the system if the fiberglass pan is worn to the extent that fibers are exposed; follow-on inspection of the fuselage frames if there is a hole worn through the fiberglass pan anywhere within the two-inches forward or aft of any frame location; repair or replacement of the damaged pan; and repair of the fuselage frames if damaged and damage is within the limits specified in the structural repair manual, as described in the alert service bulletin. Following accomplishment of the corrective actions, the alert service bulletin recommends testing the cargo loader system for proper operation. The alert service bulletin also contains instructions to contact the manufacturer for reactivation of the cargo loader system and disposition of certain inspection and repair procedures. \n\nExplanation of the Requirements of the Rule \n\tSince an unsafe condition has been identified that is likely to exist or develop on other products of this same type design, this AD would require accomplishment of the actions specified in the alert service bulletin described previously, except as discussed below. \n\nDifferences Between Alert Service Bulletin and This AD \n\tOperators should note that, although the alert service bulletin permits reactivation of the cargo loader system after contacting the manufacturer for disposition of inspection and repair procedures, this AD requires reactivation of the system and disposition of the inspection and repair procedures be accomplished in accordance with a method approved by the FAA. \n\tAlthough the alert service bulletin specifies accomplishment of inspections, this AD refers to those inspections as detailed visual inspections. The FAA finds that "detailed visual inspection" is the appropriate terminology for the inspections described in the service bulletin. Additionally, a definition of a detailed visual inspection is included in Note 2 of this proposed AD. \n\tThe alert service bulletin also specifies repetitive inspections at intervals not to exceed 300 flight cycles provided no damage is detected following accomplishment of the initial inspection. However, paragraph (a) of this AD also requires accomplishment of the repetitive inspections if the cargo loader system is reactivated after damage is repaired. \n\nInterim Action \n\tThis is considered to be interim action. The manufacturer has advised that it currently is developing a modification that will positively address the unsafe condition addressed by this AD. Once this modification is developed, approved, and available, the FAA may consider additional rulemaking.\n\n Determination of Rule's Effective Date \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. Comments Invited \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 this rule 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 Organize 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 For each issue, state what specific change to the AD is being requested.\n Include 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\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 2000-NM-286-AD." The postcard will be date stamped and returned to the commenter.\n\n Regulatory Impact \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\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 placedin the Rules Docket. A copy of it, if filed, may be obtained from the Rules Docket at the location provided under the caption "ADDRESSES." \nList of Subjects in 14 CFR Part 39 \n\tAir transportation, Aircraft, Aviation safety, Incorporation by reference, Safety. \nAdoption of the Amendment \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: PART 39 - AIRWORTHINESS DIRECTIVES \n\t1. The authority citation for part 39 continues to read as follows: Authority: 49 U.S.C. 106(g), 40113, 44701. § 39.13 (Amended) \n\t2. Section 39.13 is amended by adding the following new airworthiness directive: