AD 94-02-02

This amendment adopts a new airworthiness directive (AD) that applies to Rockwell International/Air Transport Division (Collins) DME-700 distance measuring equipment (DME) installed on aircraft. This action requires modifying these DME units to ensure they are functioning properly. Several reports of the affected DME units failing to process and update distance outputs, and reports of these units establishing a continuous restart mode upon power application prompted this AD. The actions specified by this AD are intended to prevent improper operation of this equipment, which could result in navigational errors.

Final rule.

94-02-02 ROCKWELL INTERNATIONAL/COLLINS AIR TRANSPORT DIVISION: Amendment 39-8799. Docket No. 92-CE-60-AD. \n\n\tApplicability: DME-700 distance measuring equipment (all serial numbers) (part numbers 622-4540-020, 622-4540-021, 622-4540-022, 622-4540-120, and 622-4540-121), that is installed on, but not limited to, the following model airplanes (all serial numbers), certificated in any category: \n\nManufacturer\nModels \nBoeing\nB737, B747-400, and B767 \nMcDonnell Douglas\nMD 80, MD 11 \nAirbus\nA300, A310, A300-600, A320, and A340 \nFokker\nF-100\n\tCompliance: Required within the next 12 calendar months after the effective date of this AD, unless already accomplished. \n\n\tTo prevent improper operation of these DME units, which could result in navigational errors, accomplish the following: \n\n\t(a)\tEnsure that Aeronautical Radio, Inc. (ARINC) 429 distance outputs are processed and updated by modifying the distance measuring equipment in accordance with the applicable service information presented in the chart in paragraph (c) of this AD. \n\n\t(b)\tEnsure proper initialization and correct DME distance indication by modifying the distance measuring equipment in accordance with the applicable service information presented in the chart in paragraph (c) of this AD. \n\n\t(c)\tParagraphs (a) and (b) shall be accomplished in accordance with the Accomplishment Instructions section of the applicable service bulletins (SB) presented in the following chart: \n\nCollins SB/Condition\nDate\nPart Numbers Applicable (622-4540-XXX) \nSB 20, Revision 1/Sleeping\nAugust 30, 1991\nAll applicable DME-700 Units, -020, -120, with serial number 1 through 4247. \nSB 25/ Deaf, Sleeping, and Distance Jumping\nNovember 11, 1992\nAll applicable DME-700 Units, converts -020, -021, or -022 to -023. SB 20 must be installed prior to or in conjunction with SB 25. SB 24 is incorporated by SB 25. \nSB 26/Deaf, Sleeping, and Distance Jumping\nOctober 21, 1992\nAll applicable DME-700 Units, converts -120 or -121 to -122. SB 20 must be installed prior to or in conjunction with SB 26. SB 26 eliminates the need for SB 21.\n\tNOTE 1: The sleeping DME modification referenced in SB 20 was incorporated at manufacture beginning with serial number 4248. \n\n\t(d)\tSpecial flight permits may be issued in accordance with 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(e)\tAn alternative method of compliance or adjustment of the compliance time that provides an equivalent level of safety may be approved by the Manager, Wichita Aircraft Certification Office (ACO), 1801 Airport Road, Room 100, Mid-Continent Airport, Wichita, Kansas 67209. The request shall be forwarded through an appropriate FAA Maintenance Inspector, who may add comments and then send it to the Manager, Wichita ACO. \n\n\tNOTE 2: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Wichita ACO. \n\n\t(f)\tThe modifications required by this AD shall be done in accordance with Collins Service Bulletin 20, Revision 1, DME-700-34-20, dated August 30, 1991; Collins Service Bulletin 25, DME-700-34-25, dated November 11, 1992; and Collins Service Bulletin 26, DME-700-34-26, dated October 21, 1992, 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 Rockwell International/Collins Air Transport Division, 400 Collins Road, NE; Cedar Rapids, Iowa 52498. Copies may be inspected at the FAA, Central Region, Office of the Assistant Chief Counsel, Room 1558, 601 E. 12th Street, Kansas City, Missouri, or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC. \n\n\t(g)\tThis amendment (39-8799) becomes effective on February 21, 1994.

A proposal to amend part 39 of the Federal Aviation Regulations to include an AD that applies to certain Collins DME-700 distance measurement equipment installed on aircraft was published in the Federal Register on January 25, 1993 (58 FR 5949). The action proposed to require modifying these DME units to ensure that they are functioning properly. The proposed modifications would be accomplished in accordance with the following Collins service bulletins (SB) (1) SB 20, Revision 1, DME-700-34-20, dated August 30, 1991, which when incorporated prevents a condition known as "sleeping DME's"; and (2) Collins SB 24, DME-700-34-24, dated May 15, 1992; Collins SB 25, DME-700-34-25, dated November 11, 1992; and Collins SB 26, DME-700-34-26, dated October 21, 1992, as applicable, which when incorporated prevent a condition known as "deaf DME's". \n\n\tInterested persons have been afforded an opportunity to participate in the making of this amendment. Based on thecomments received, the proposal was changed to add a modification that went beyond the scope of that which was originally proposed. \n\n\tAccordingly, the FAA issued a supplementary NPRM that incorporated minor revisions and added the additional modification. The proposed actions specified in the Supplemental NPRM would be accomplished in accordance with the following, as applicable:\n\n\nCollins SB/\n\nPart Numbers Applicable\nCondition\n Date\n(622-4540-XXX)\n\n\n\n\n\n\n\n\n\nSB 20, \nRevision 1/\nSleeping\nAugust 30, 1991\nAll applicable DME-700 Units,\n-020, -120, with serial number\n1 through 4247.\n\n\n\nSB 25/\nNovember 11, 1992\nAll applicable DME-700 Units,\nDeaf and\n\nconverts -020, -021, or -022\nDistance\n\nto -023. SB 20 must be\nJumping\n\ninstalled prior to or in\n\n\nconjunction with SB 25. SB 24 \n\n\nis incorporated by SB 25.\n\n\n\nSB 26/\nOctober 21, 1992\nAll applicable DME-700 Units,\nDeaf and \n\nconverts -120 or -121 to -122.\nDistance \n\nSB 20 must be installed prior\nJumping\n\nto or in conjunction with SB \n\n\n26. SB 26 eliminates the need \n\n\nfor SB 21.\n\n\tInterested persons were again afforded an opportunity to comment on the proposed action. Due consideration has been given to the five comments received.\n\n\tTwo commenters concur with the proposed rule as written.\n\n\tAnother commenter (Collins) states that there are two errors in the part numbers referenced in the proposed AD: (1) part number (P/N) 622-4540-022 was referenced as P/N 622-4540-22 in the Applicability section of the AD; and (2) in the chart in paragraph (c) of the proposed AD, the sentence that consists of the following words: "All applicable DME-700 Units, Converts -022, -021, or -022 to -023." should be changed to "All applicable DME-700 Units, Converts -020, -021, or -022 to -023." The FAA concurs and has changed the proposed AD accordingly. \n\n\tOne commenter reports that the Airbus Model A330 airplane is not yet certificated, and should not be included in the list of affected airplane models. The FAA concurs that this airplane is not certificated and has deleted it from the list of possible affected airplanes. However, the Applicability section of the proposed AD is worded as "DME equipment that is installed on, but not limited to, the following model airplanes (all serial numbers), certificated in any category:". If this airplane would become certificated for operation with the Collins DME-700 equipment, then this action would apply to these airplanes. \n\n\tAnother commenter states that these DME units were never certificated on Boeing Model B757 airplanes, and should therefore be removed from the applicability of the proposed AD. The FAA concurs and has revised the proposed AD accordingly.\n\n\tThis same commenter suggests several minor editorial revisions and corrections to increase the understanding of the proposed AD. The FAA concurs that these changes would improve clarity and has revised the proposed AD accordingly. \n\n\tAfter careful review of all available information including the comments noted above, the FAA has determined that air safety and the public interest require the adoption of the rule as proposed except for the changes referenced above and minor editorial corrections. The FAA has determined that these changes and corrections will not change the meaning of the AD nor add any additional burden upon the public than was already proposed.\n\n\tThe condition specified by the required action is not caused by actual hours time-in-service (TIS) of the airplane that the equipment is installed in. There is no correlation between improper operation of the equipment and the age or number of times the equipment is utilized. Based on this, the compliance time of this AD is presented in calendar time instead of hours TIS.\n\n\tThe FAA estimates that 518 DME-700 units installed on airplanes in the U.S. registry will be affected by this AD, that it will take approximately 7 workhours per unit to accomplish the required action, and that the average labor rate is approximately $55 an hour. Parts will be provided by the manufacturer at no cost to the owner/operator. Based on these figures, the total cost impact of this AD on U.S. operators is estimated to be $199,430. This cost figure is based on the assumption that none of the affected airplane owners/operators have accomplished the required action.\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 copy of the final evaluation prepared for this action is contained in the Rules Docket. A copy of it may be obtained by contacting the Rules Docket at the location provided under the caption "ADDRESSES".\n\nList of Subjects in 14 CFR Part 39\n\tAir transportation, Aircraft, Aviation safety, Incorporation by reference, Safety.\n\nAdoption of the Amendment\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\t1.\tThe authority citation for part 39 continues to read as follows:\nAuthority: 49 U.S.C. App. 1354(a), 1421 and 1423; 49 U.S.C. 106(g); and 14 CFR 11.89.\n\nSection 39.13 - (AMENDED)\n\t2.\tSection 39.13 is amended by adding the following new AD: