AD 94-09-12

This amendment adopts a new airworthiness directive (AD), applicable to certain McDonnell Douglas Model DC-8, DC-9, and DC-9-80 series airplanes; Model MD-88 airplanes; and C-9 (military) airplanes; that requires inspection of the center and side windshields, and replacement of discrepant windshields. This amendment is prompted by reports that the core ply of certain windshields was incorrectly tempered during the manufacturing process. The actions specified by this AD are intended to prevent failure of the windshield.

Final rule.

94-09-12 McDONNELL DOUGLAS: Amendment 39-8901. Docket 93-NM-156-AD.\t\n\n\tApplicability: Model DC-8-60 and -70 series airplanes, on which the center windshield has been replaced after February 1992; and Model DC-9-10, -20, -30, -40, and -50 series airplanes, Model DC-9-81, -82, -83, and -87 airplanes, Model MD-88 airplanes, and C-9 (military) airplanes, on which the center and/or side (glass) windshield(s) has been replaced after February 1992; certificated in any category. \n\n\tCompliance: Required as indicated, unless accomplished previously. \n\n\tNOTE 1: Replacement of any subject windshield that has been accomplished prior to the effective date of this amendment in accordance with McDonnell Douglas DC-8 Service Bulletin A56-16, dated June 15, 1993, or Revision 1, dated July 1, 1993 (for Model DC-8 series airplanes); or McDonnell Douglas DC-9 Alert Service Bulletin A56-15, dated June 15, 1993, or Revision 1, dated September 15, 1993; is considered acceptable for compliance with the applicable action specified in this amendment. \n\n\tNOTE 2: This AD only addresses center and side flight compartment windshields made of glass. Windshields used in other locations on these airplanes and windshields manufactured with materials other than glass are not addressed in this AD. \n\n\tTo prevent failure of the windshield, accomplish the following: \n\n\t(a)\tFor Model DC-8-60 and -70 series airplanes: Within 30 days after the effective date of this AD, perform a visual inspection of the center windshield to determine the manufacturer. \n\n\t\t(1)\tIf the windshield was not manufactured by Pilkington Aerospace: No further action is required by this AD. \n\n\t\t(2)\tIf the center windshield, part number 5887275-501, was manufactured by Pilkington Aerospace: Prior to further flight, replace the center windshield with one of the windshields specified in paragraph (a)(2)(i), (a)(2)(ii), or (a)(2)(iii) of this AD, in accordance with McDonnell Douglas DC-8 Alert Service BulletinA56-16, Revision 2, dated December 13, 1993. \n\n\t\t\t(i)\tA center windshield that was not manufactured by Pilkington Aerospace; or \n\n\t\t\t(ii)\tA center windshield that has been manufactured by Pilkington Aerospace, but recertified and re-identified by Pilkington Aerospace. \n\n\t\t\t(iii)\tA center windshield that was manufactured by Pilkington Aerospace after September 30, 1993. \n\n\t(b)\tFor Model DC-9-10, -20, -30, -40, and -50 series airplanes; Model DC-9-81, -82, -83, and -87 airplanes; Model MD-88 airplanes; and C-9 (military) airplanes: Within 30 days after the effective date of this AD, perform a visual inspection of the center windshield and side windshield to determine the manufacturer. \n\n\t\t(1)\tIf the center and side windshields were not manufactured by Pilkington Aerospace: No further action is required by this AD. \n\n\t\t(2)\tIf the center windshield, part number 5887275-501, or side windshields, part numbers 5912290-501 and 5912290-502, were manufactured by Pilkington Aerospace: Prior to further flight, replace the center and/or side windshield(s) with one of the windshields specified in paragraph (b)(2)(i), (b)(2)(ii), or (b)(2)(iii) of this AD, in accordance with McDonnell Douglas DC-9 Alert Service Bulletin A56-15, Revision 2, dated November 9, 1993. \n\n\t\t\t(i)\tA center and/or side windshield(s) that was not manufactured by Pilkington Aerospace; or \n\n\t\t\t(ii)\tA center and/or side windshield(s) that has been manufactured by Pilkington Aerospace, but recertified and re-identified by Pilkington Aerospace. \n\n\t\t\t(iii)\tA center and/or side windshield(s) that was manufactured by Pilkington Aerospace after September 30, 1993. \n\n\t(c)\tAs of the effective date of this AD, no person shall install on any airplane a center windshield, part number 5887275-501, or side windshields, part numbers 5912290-501 and 5912290-502, that have been manufactured by Pilkington Aerospace between February 1, 1992, and September 30, 1993, inclusive. Those windshields must be recertified and re-identified by Pilkington Aerospace before use. \n\n\t(d)\tAn 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, Transport Airplane Directorate. 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 3: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Los Angeles ACO. \n\n\t(e)\tSpecial flight permits may be issued in accordance with Federal Aviation Regulations (FAR) 21.197 and 21.199 to operate the airplane to a location where the requirements of this AD can be accomplished. \n\n\t(f)\tThe replacement shall be done in accordance with McDonnell Douglas DC-8 Alert Service Bulletin A56-16, Revision 2, dated December 13,1993; or McDonnell Douglas DC-9 Alert Service Bulletin A56-15, Revision 2, dated November 9, 1993; as applicable. 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 McDonnell Douglas Corporation, P.O. Box 1771, Long Beach, California 90801-1771, Attention: Business Unit Manager, Technical Administrative Support, Department L51, M.C. 2-98. Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the FAA, Transport Airplane Directorate, Los Angeles Aircraft Certification Office, 3229 East Spring Street, Long Beach, California; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC. \n\n\t(g)\tThis amendment becomes effective on June 9, 1994.

A proposal to amend part 39 of the Federal Aviation Regulations to include an airworthiness directive (AD) that is applicable to certain McDonnell Douglas Model DC-8, DC-9, and DC-9-80 series airplanes; Model MD-88 airplanes; and C-9 (military) airplanes was published as a supplemental notice of proposed rulemaking (NPRM) in the Federal Register on February 15, 1994 (59 FR 7233). That action proposed to require inspection of the center and side windshields, and replacement of discrepant windshields. \n\n\tInterested persons have been afforded an opportunity to participate in the making of this amendment. Due consideration has been given to the comments received. \n\n\tThree commenters support the proposed rule. \n\n\tOne commenter requests that inspections performed prior to the effective date of the AD be considered acceptable for compliance with the inspection requirement in the proposal. The FAA concurs. As allowed by the phrase, "unless accomplished previously," in the "Compliance" section of this AD, if the inspection has been accomplished prior to the effective date of the AD, this AD does not require that it be repeated. Therefore, no change to the final rule is necessary. \n\n\tOne commenter requests that the final rule be revised to include the option of reviewing purchasing records in lieu of the proposed inspection requirement. The commenter asserts that a review of purchasing records would be more cost effective, and safety would not be compromised since the end result would be the same: a determination of the manufacturing source of the windshields. The FAA does not concur. Since tracking systems for shipping and purchasing records vary from operator to operator, the possibility exists for windshields to be tracked by part number alone. These common part numbers may be assigned to several manufacturers. Therefore, purchasing records would not be reliable in determining the manufacturing source of windshields. \n\n\tOne commenter requests that the proposed compliance time of 30 days to inspect the windshields be extended to 90 days or at the next regularly scheduled "B" check. The commenter states that a compliance time of 30 days would impose an unnecessary hardship on operators of large fleets. Two commenters also express concern that replacement parts would not be available in sufficient quantities; therefore, the extension in compliance time would give the manufacturer sufficient time to produce an adequate quantity of replacement windshields. The FAA does not concur. In developing an appropriate compliance time for this action, the FAA considered not only the degree of urgency associated with addressing the subject unsafe condition, but the availability of required parts and the practical aspect of inspecting and installing the necessary parts within a maximum interval of time allowable for all affected airplanes to continue to operate without compromising safety. The FAA has verified that, of the original 730 discrepant windshields known to have been produced and in service, 599 (82%) have already been removed from service and returned to the vendor; that leaves only 131 windshields remaining in service. Further, the FAA also has verified that an adequate supply of replacement windshields will be available for affected operators to accomplish the requirements of this AD within the 30-day compliance time. In light of all of these factors, the FAA has determined that the 30-day compliance time is warranted and appropriate. However, under the provisions of paragraph (d) of the final rule, operators may apply for the approval of an alternative method of compliance or adjustment of the compliance time by submitting justification for such an alternative or adjustment to the FAA. \n\n\tOne commenter requests that proposed paragraphs (a)(2)(ii), (b)(2)(ii), and (c) be changed to limit applicability only to those airplanes on which the windshield has been replaced after February1992. The FAA does not consider that this suggested change is necessary. Since the applicability statement of the AD states that the AD applies to "airplanes on which the. . .windshield has been replaced after February 1992," that statement applies to paragraphs (a), (b), and (c) of the AD. Therefore, no change to the final rule is warranted. \n\n\tThis same commenter requests that the final rule be revised to include a requirement to inspect for discrepant windshields that are identifiable by part numbers and serial numbers beginning with the letters "SWU." The FAA does not concur. Windshields that have a part number or serial number beginning with "SWU" are made of acrylic and, as such, are not subject to the unsafe condition addressed by this AD. The unsafe condition addressed by this AD is the result of incorrect tempering of the core ply of certain glass windshields during the manufacturing process. NOTE 2 has been added to the final rule to make clear that the requirementsof this AD apply only to windshields made of glass. \n\n\tAfter careful review of the available data, including the comment noted above, the FAA has determined that air safety and the public interest require the adoption of the rule as proposed. \n\n\tThere are approximately 235 Model DC-8 series airplanes of the affected design in the worldwide fleet. The FAA estimates that 140 airplanes of U.S. registry will be affected by this AD, that it will take approximately 0.5 work hour per airplane to accomplish the required inspection, and that the average labor rate is $55 per work hour. Based on these figures, the total cost impact of the AD on U.S. operators of Model DC-8 series airplanes is estimated to be $3,850, or $27.50 per airplane. \n\n\tThere are approximately 1,978 Model DC-9 and DC-9-80 series airplanes, Model MD-88 airplanes, and C-9 (military) airplanes of the affected design in the worldwide fleet. The FAA estimates that 1,079 airplanes of U.S. registry will be affected by this AD, that it will take approximately 0.5 work hour per airplane to accomplish the required inspection, and that the average labor rate is $55 per work hour. Based on these figures, the total cost impact of the AD on U.S. operators of Model DC-9 and DC-9-80 series airplanes, Model MD-88 airplanes, and C-9 (military) airplanes is estimated to be $29,673, or $27.50 per airplane. \n\n\tBased on the figures discussed above, the total cost impact of the AD actions on U.S. operators is estimated to be $33,523. \n\n\tShould an inspection reveal that a discrepant windshield was installed, the replacement of that windshield will require approximately 10 additional work hours to accomplish, at an average labor rate of $55 per work hour. Required replacement parts will be provided at no cost to operators. Based on these figures, the total cost impact for the replacement of discrepant windshields for U.S. operators will be $550 per airplane. \n\n\tThe total cost impact figures discussed above are based on assumptions that no operator has yet accomplished any of the requirements of this AD action, and that no operator would accomplish those actions in the future if this AD were not adopted. However, the FAA has been advised that 599 out of 730 discrepant windshields already have been identified and returned by affected operators; therefore, the future total cost impact of this AD is expected to be much less that the figures indicated above. \n\n\tThe regulations adopted herein will not have substantial direct effects 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, in accordance with Executive Order 12612, it is determined that this final rule does not have sufficient federalism implications to warrant the preparation of a Federalism Assessment. \n\n\tFor the reasons discussed above, I certify that this action (1) is not a "significant regulatory action" under Executive Order 12866; (2) is not a "significant rule" under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and (3) will not have a significant economic impact, positive or negative, on a substantial number of small entities under the criteria of the Regulatory Flexibility Act. A final evaluation has been prepared for this action and it is contained in the Rules Docket. A copy of it 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 14 CFR part 39 of the Federal Aviation Regulations as follows: \n\nPART 39 - AIRWORTHINESS DIRECTIVES \n\n\t1.\tThe authority citation for part 39 continues to read as follows: \n\nAuthority:49 U.S.C. App. 1354(a), 1421 and 1423; 49 U.S.C. 106(g); and 14 CFR 11.89. § 39.13 - (Amended) \n\n\t2.\tSection 39.13 is amended by adding the following new airworthiness directive: