AD 98-26-51

This document publishes in the Federal Register an amendment adopting Airworthiness Directive (AD) 98-26-51 that was sent previously to all known U.S. owners and operators of certain McDonnell Douglas Model DC-8 series airplanes by individual telegrams. This AD requires a revision to the Airplane Flight Manual to specify restrictions on operating if any pressurization anomaly is detected. This AD also requires a one-time inspection to detect discrepancies and cracking of the main deck cargo door in the immediate area of the bolts attaching the latch fittings, and repair, if necessary. This action is prompted by a report that a cabin pressurization anomaly was detected on a McDonnell Douglas Model DC-8 series airplane, and by subsequent investigation, which revealed fatigue cracking in the structure of the main deck cargo door. The actions specified by this AD are intended to detect and correct fatigue cracking in the structure of the main deck cargo door, which could result in cabin decompression of the airplane and loss of the main deck cargo door, and consequent reduced controllability of the airplane.\n\n\tEffective February 3, 1999, to all persons except those persons to whom it was made immediately effective by telegraphic AD T98-26-51, issued December 18, 1998, which contained the requirements of this amendment. \n\n\tComments for inclusion in the Rules Docket must be received on or before March 30, 1999.

Final rule; request for comments.

98-26-51 MCDONNELL DOUGLAS: Amendment 39-11016. Docket 98-NM-379-AD.\n\n\tApplicability: Model DC-8 series airplanes that have been converted from a passenger-carrying to a cargo-carrying ("freighter") configuration in accordance with Supplemental Type Certificate (STC) SA1802SO.\n\n\tNOTE 1: This AD applies to each airplane identified in the preceding applicability provision, regardless of whether it has been otherwise 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 (g) 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 fatigue cracking in the structure of the main deck cargo door, which could result in cabin decompression of the airplane and loss of the main deck cargo door, and consequent reduced controllability of the airplane, accomplish the following: \n\n\t(a)\tWithin 24 hours after the effective date of this AD, revise the Limitations Section of the FAA-approved Airplane Flight Manual (AFM) to include the following information. This may be accomplished by inserting a copy of this AD into the AFM.\n\n"IF ANY UNEXPECTED LOSS OF CABIN PRESSURE OCCURS, DO NOT INCREASE CABIN PRESSURE. IMMEDIATELY SELECT A HIGHER CABIN ALTITUDE AND, AS SOON AS POSSIBLE, DESCEND TO A LOWER FLIGHT ALTITUDE."\n\n\n\t(b)\tExcept as provided by paragraph (d) of this AD, within 7 days after the effective date of this AD: Perform an internal detailed visual inspection to detect cracking or any discrepancy of the main deck cargo door in the immediate area of the bolts attaching the latch fittings. Inspect for cracking or any discrepancy of the skin in the immediate area of the fastener heads, and for loose or missing fasteners. In addition, prior to the internal detailed visual inspection, clean and degrease the inside structure where the latch fitting bolts attach to the frames, and perform a detailed visual inspection of the frames to detect cracking emanating from the bolt holes and at the bend radius of the frames.\n\n\tNOTE 2: Removal of the inner skin of the main deck cargo door is not necessary to gain access and inspect for cracking emanating from the bolt holes and at the bend radius of the frames.\n\n\t(c)\tPrior to accomplishment of the inspections required by paragraph (b) of this AD, notify an appropriate FAA Principal Maintenance Inspector of the date and time the inspection required by paragraph (b) of this AD is to be accomplished.\n\n\t(d)\tFor airplanes on which there have been reports of cabin pressurization anomalies or illuminations of the main deck cargo door warning light within 30 days prior to the effective date of this AD or within 7 days after the effective date of this AD: Perform the inspection required by paragraph (b) of this AD prior to further flight.\n\n\t(e)\tIf any discrepancy is detected during the inspections required by paragraph (b) of this AD, prior to further flight, repair in accordance with a method approved by the Manager, Atlanta Aircraft Certification Office (ACO), FAA, Small Airplane Directorate.\n\n\t(f)\tWithin 24 hours after accomplishment of the inspections required by paragraph (b) of this AD, or within 24 hours after the effective date of this AD, whichever occurs later, submit a report of the inspection results (both positive and negative findings) to the Manager, Atlanta ACO, FAA, Small Airplane Directorate, One Crown Center, 1895 Phoenix Boulevard, Suite 450, Atlanta, Georgia 30349; fax (770) 703-6097.Information collection requirements contained in this regulation have been approved by the Office of Management and Budget (OMB) 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\n\t(g)\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, Atlanta ACO. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, Atlanta 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 Atlanta ACO.\n\n\t(h)\tSpecial 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 beaccomplished. \n\n\t(i)\tThis amendment becomes effective on February 3, 1999, to all persons except those persons to whom it was made immediately effective by telegraphic AD T98-26-51, issued on December 18, 1998, which contained the requirements of this amendment.

On December 18, 1998, the FAA issued telegraphic AD T98-26-51, which is applicable to certain McDonnell Douglas Model DC-8 series airplanes modified in accordance with Supplemental Type Certificate (STC) SA1802SO. That action was prompted by a report indicating that a cabin pressurization anomaly was detected on a McDonnell Douglas Model DC-8 series airplane modified in accordance with STC SA1802SO. Investigation revealed fatigue cracking in the structure of the main deck cargo door. Propagation of cracks on the frames and inner skin of the latch fitting supports could lead to severed frames and inner skin at the latch fitting supports of the main deck cargo door. This condition, if not corrected, could result in cabin decompression of the airplane and loss of the main deck cargo door, and consequent reduced controllability of the airplane.\n\nExplanation of Requirements of the Rule\n\n\tSince the unsafe condition described is likely to exist or developon other airplanes of the same type design, the FAA issued telegraphic AD T98-26-51 to detect and correct fatigue cracking in the structure of the main deck cargo door, which could result in cabin decompression of the airplane and loss of the main deck cargo door, and consequent reduced controllability of the airplane. The AD requires a revision to the FAA-approved Airplane Flight Manual to specify restrictions on operating if any pressurization anomaly is detected. The AD also requires a one-time detailed visual inspection to detect discrepancies and cracking of the main deck cargo door in the immediate area of the bolts attaching the latch fittings, and repair, if necessary.\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\n\tSince it was found that immediate corrective action was required, notice and opportunity for prior public comment thereon were impracticable and contrary tothe public interest, and good cause existed to make the AD effective immediately by individual telegrams issued on December 18, 1998, to all known U.S. owners and operators of McDonnell Douglas Model DC-8 series airplanes modified in accordance with STC SA1802SO. These conditions still exist, and the AD is hereby published in the Federal Register as an amendment to section 39.13 of the Federal Aviation Regulations (14 CFR 39.13) to make it effective to all persons.\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 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\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 98-NM-379-AD." The postcard will be date stamped and returned to the commenter.\n\nRegulatory Impact\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\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, 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\nAuthority: 49 U.S.C. 106(g), 40113, 44701. \n\n§ 39.13 (Amended)\n\n\t2. Section 39.13 is amended by adding the following new airworthiness directive: