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Proposed Rule

Airworthiness Directives; McDonnell Douglas Model DC-10-10, DC-10-10F, DC-10-15, DC-10-30, DC-10-30F, DC-10-30F (KC10A and KDC-10), DC-10-40, and DC-10-40F Airplanes

Document Details

Information about this document as published in the Federal Register.

Published Document

This document has been published in the Federal Register. Use the PDF linked in the document sidebar for the official electronic format.

Start Preamble

AGENCY:

Federal Aviation Administration, DOT.

ACTION:

Supplemental notice of proposed rulemaking; reopening of comment period.

SUMMARY:

This document revises an earlier proposed airworthiness directive (AD), applicable to certain McDonnell Douglas airplanes, that would have required inspections of the linear variable differential transducers (LVDTs) of the autopilot for discrepancies, and follow-on actions, if necessary. This new action revises the proposed rule by expanding the applicability. The actions specified by this new proposed AD are intended to prevent failure of the LVDTs, which could result in an automatic pitch trim malfunction or an autopilot disconnect, and consequent reduced controllability of the airplane. This action is intended to address the identified unsafe condition.

DATES:

Comments must be received by April 11, 2003.

ADDRESSES:

Submit comments in triplicate to the Federal Aviation Administration (FAA), Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 2001-NM-358-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056. Comments may be inspected at this location between 9 a.m. and 3 p.m., Monday through Friday, except Federal holidays. Comments may be submitted via fax to (425) 227-1232. Comments may also be sent via the Internet using the following address: 9-anm-nprmcomment@faa.gov. Comments sent via fax or the Internet must contain “Docket No. 2001-NM-358-AD” in the subject line and need not be submitted in triplicate. Comments sent via the Internet as attached electronic files must be formatted in Microsoft Word 97 for Windows or ASCII text.

The service information referenced in the proposed rule may be obtained from Boeing Commercial Airplane Group, P.O. Box 3707, Seattle, Washington 98124-2207. This information may be examined at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington.

Start Further Info

FOR FURTHER INFORMATION CONTACT:

Ron Atmur, Aerospace Engineer, Airframe Branch, ANM-120L, FAA, Los Angeles Aircraft Certification Office, 3960 Paramount Boulevard, Lakewood, California 90712-4137; telephone (562) 627-5224; fax (562) 627-5210.

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SUPPLEMENTARY INFORMATION:

Comments Invited

Interested persons are invited to participate in the making of the proposed 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 above. All communications received on or before the closing date for comments, specified above, will be considered before taking action on the proposed rule. The proposals contained in this action may be changed in light of the comments received.

Submit comments using the following format:

  • 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.
  • For each issue, state what specific change to the proposed AD is being requested.
  • Include justification (e.g., reasons or data) for each request.

Comments are specifically invited on the overall regulatory, economic, environmental, and energy aspects of the proposed 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 summarizing each FAA-public contact concerned with the substance of this proposal will be filed in the Rules Docket.

Commenters wishing the FAA to acknowledge receipt of their comments submitted in response to this action must submit a self-addressed, stamped postcard on which the following statement is made: “Comments to Docket No. 2001-NM-358-AD.” The postcard will be date stamped and returned to the commenter.

Availability of NPRMs

Any person may obtain a copy of this NPRM by submitting a request to the FAA, Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 2001-NM-358-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056.Start Printed Page 12619

Discussion

A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) to add an airworthiness directive (AD), applicable to certain McDonnell Douglas Model DC-10-10, DC-10-10F, DC-10-15, DC-10-30, DC-10-30F, DC-10-30F (KC10A and KDC-10), MD-10-10F, and MD-10-30F airplanes, was published as a notice of proposed rulemaking (NPRM) in the Federal Register on August 23, 2002 (67 FR 54593). That NPRM would have required inspections of the linear variable differential transducers (LVDTs) of the autopilot for discrepancies, and follow-on actions, if necessary. That NPRM was prompted by information received from the manufacturer that certain McDonnell Douglas airplanes having LVDTs were delivered with undersize nylok elements on the threaded extension end. That condition, if not corrected, could result in failure of the LVDTs and an automatic pitch trim malfunction or an autopilot disconnect, and consequent reduced controllability of the airplane.

Actions Since Issuance of Previous Proposal

The applicability statement of the NPRM specified that it would apply to certain McDonnell Douglas Model DC-10-10, DC-10-10F, DC-10-15, DC-10-30, DC-10-30F, DC-10-30F (KC10A and KDC-10), MD-10-10F, and MD-10-30F airplanes; as listed in Boeing Alert Service Bulletin DC10-22A126, dated October 31, 2001; and Boeing Alert Service Bulletin DC10-22A127, dated December 17, 2001. We inadvertently omitted specifying Model DC-10-40 and DC-10-40F airplanes; however, those airplanes are listed in the specified service bulletins. In addition, it has been determined that Model MD-10-10F and MD-10-30F airplanes have a different design and are not affected by the NPRM. For the convenience of affected operators, the FAA has changed the applicability statement of this supplemental NPRM to reflect these changes.

Comments

Due consideration has been given to the comments received in response to the NPRM:

Request To Change Paragraph (a)(1)

One commenter asks that the language in paragraph (a)(1) of the NPRM which specifies, “including replacing the LVDT with a new LVDT and doing an automatic pitch trim adjustment/test” be changed. The commenter states that the manufacturer has repaired several LVDTs with the affected serial numbers and those LVDTs are being installed on the airplanes. The commenter suggests that the language state, “including replacing the LVDT with a new LVDT, or LVDT with an affected serial number that was repaired after January 22, 2001, by the parts manufacturer; and doing an automatic pitch trim adjustment/test.”

We do not agree with the commenter. There is no specific designation or modification level for identifying the correct nylok strip size to be installed on a repaired LVDT; only a label titled “Rework” and the date are engraved on those units. All returned LVDT units are marked “Rework” after repair, regardless of the reason for repair, and returned to operators with the same serial number. We acknowledge that certain LVDT units have been repaired by the parts manufacturer by adding the correct nylok strip size. However, we do not have any data validating proper control and identification of the nylok strip size required for installation in an LVDT with an affected serial number. In light of these factors, we find that no change to the supplemental NPRM is necessary in this regard.

The same commenter requests clarifying the text in paragraph (a)(1) of the NPRM which specifies, “If no discrepancy is found, install a shield assembly per Condition 2 of the service bulletin.” The commenter states that Condition 2 of the service bulletin specifies that no further action is needed if no discrepancy is found. The commenter believes that if no discrepancy is found, the existing shield on the LVDT would be reinstalled if removed during any inspection/repair process. The commenter adds that the text in the NPRM implies installing something additional, which is not the case.

We agree with the commenter and have clarified paragraph (a)(1) of this supplemental NPRM.

Request To Change Paragraph (b)

The same commenter asks that paragraph (b) of the NPRM be changed to state, “As of the effective date of this AD, no one may install a LVDT on any airplane autopitch trim system with a serial number listed in the ‘Affected Serial Numbers’ table in Figure 1 of Boeing Alert Service Bulletin DC10-22A127, dated December 17, 2001; unless the LVDT serial number has been repaired by OEM Kavlico after January 22, 2001.”

We do not agree with the commenter. The intent of paragraph (b) of this supplemental NPRM is to prohibit any LVDT with a serial number listed in the “Affected Serial Numbers” table in Figure 1 of the service bulletin from being installed on any airplane after the effective date of this AD. No change to the supplemental NPRM is necessary in this regard.

Explanation of Editorial Change

We have changed the service bulletin citations in this supplemental NPRM to exclude the Evaluation Forms. The forms are intended to be completed by operators and submitted to the manufacturer to provide input on the quality of the service bulletins; however, this AD does not include such a requirement.

Conclusion

Since the change in applicability expands the scope of the originally proposed rule, we have determined that it is necessary to reopen the comment period to provide additional opportunity for public comment.

Cost Impact

There are approximately 394 airplanes of the affected design in the worldwide fleet. The FAA estimates that 252 airplanes of U.S. registry would be affected by this proposed AD.

It would take approximately 1 work hour per airplane to accomplish the inspection specified in Boeing Alert Service Bulletin DC10-22A126, at an average labor rate of $60 per work hour. Based on these figures, the cost impact of this proposed inspection on U.S. operators is estimated to be $15,120, or $60 per airplane.

It would take approximately 1 work hour per airplane to accomplish the inspections specified in Boeing Alert Service Bulletin DC10-22A127, at an average labor rate of $60 per work hour. Based on these figures, the cost impact of these proposed inspections on U.S. operators is estimated to be $15,120, or $60 per airplane.

Should an operator be required to perform the follow-on actions specified in Boeing Alert Service Bulletin DC10-22A126, the cost estimates are as follows:

  • Condition 2-Repair/inspect: 1 work hour per airplane at $60 per work hour.
  • Condition 4-Realign: 1 work hour per airplane at $60 per work hour.
  • Condition 5-Replace LVDT: 1 work hour per airplane at $60 per work hour; estimated parts cost of $900.
  • Condition 6-Replace hangar: 1 work hour per airplane at $60 per work hour; estimated parts cost of $100.

Should an operator be required to perform the follow-on actions specified in Boeing Alert Service Bulletin DC10-22A127, the cost estimates are as follows:

  • Option 1-Replace LVDT and do adjustment/test: 2 work hours per Start Printed Page 12620airplane at $60 per work hour; estimated parts cost of $900.
  • Option 2-Install a heat shrinkable sleeve and inspect: 2 work hours per airplane at $60 per work hour.

The cost impact figures discussed above are based on assumptions that no operator has yet accomplished any of the proposed requirements of this AD action, and that no operator would accomplish those actions in the future if this AD were not adopted. The cost impact figures discussed in AD rulemaking actions represent only the time necessary to perform the specific actions actually required by the AD. These figures typically do not include incidental costs, such as the time required to gain access and close up, planning time, or time necessitated by other administrative actions.

Regulatory Impact

The regulations proposed herein would 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 proposal would not have federalism implications under Executive Order 13132.

For the reasons discussed above, I certify that this proposed regulation (1) is not a “significant regulatory action” under Executive Order 12866; (2) is not a “significant rule” under the DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and (3) if promulgated, 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 draft regulatory 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.

Start List of Subjects

List of Subjects in 14 CFR Part 39

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The Proposed Amendment

Accordingly, pursuant to the authority delegated to me by the Administrator, the Federal Aviation Administration proposes to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) as follows:

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PART 39—AIRWORTHINESS DIRECTIVES

1. The authority citation for part 39 continues to read as follows:

Start Authority

Authority: 49 U.S.C. 106(g), 40113, 44701.

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[Amended]

2. Section 39.13 is amended by adding the following new airworthiness directive:

McDonnell Douglas: Docket 2001-NM-358-AD.

Applicability: Model DC-10-10, DC-10-10F, DC-10-15, DC-10-30, DC-10-30F, DC-10-30F (KC10A and KDC-10), DC-10-40, and DC-10-40F airplanes; as listed in Boeing Alert Service Bulletin DC10-22A126, dated October 31, 2001; and Boeing Alert Service Bulletin DC10-22A127, dated December 17, 2001; certificated in any category.

Note 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.

Compliance: Required as indicated, unless accomplished previously.

To prevent failure of the linear variable differential transducers (LVDTs) of the autopilot, which could result in an automatic pitch trim malfunction or an autopilot disconnect, and consequent reduced controllability of the airplane, accomplish the following:

Detailed Inspections/Follow-On Actions

(a) Within 90 days after the effective date of this AD: Do the detailed inspections of the LVDTs of the autopilot for discrepancies as required by paragraphs (a)(1) and (a)(2) of this AD.

Note 2:

For the purposes of this AD, a detailed 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.”

(1) Inspect the LVDTs for affected serial numbers (with undersize nylok elements) per Figure 1 of Boeing Alert Service Bulletin DC10-22A127, dated December 17, 2001, excluding Evaluation Form. If any affected serial number is found, before further flight, do either Option 1 (including replacing the LVDT with a new LVDT and doing an automatic pitch trim adjustment/test), or Option 2 (including installing a heat-shrinkable sleeve over the LVDT jamnut and doing repetitive inspections for any loose jamnut every 500 flight hours until the LVDT is replaced with a new LVDT), of Condition 1 of the service bulletin, per the service bulletin. If any discrepancy is found, before further flight, replace the LVDT with a new LVDT. If no discrepancy is found, no further action is required by this paragraph.

(2) Inspect the shear rivets of the LVDTs of the drive assembly of the automatic pitch trim for discrepancies (shearing and/or looseness), per Boeing Alert Service Bulletin DC10-22A126, dated October 31, 2001, excluding Evaluation Form. If any discrepancy is found, before further flight, do Conditions 2 through 6 (including repairing the driver assembly and inspecting the LVDT within 9 months after doing the repair; doing an automatic pitch trim adjustment/test; aligning the LVDT; replacing the existing LVDT with a new LVDT; and replacing the hangar assembly with a new assembly), as applicable, of the service bulletin, per the service bulletin. If no discrepancy is found, no further action is required by this paragraph.

Part Installation

(b) As of the effective date of this AD, no one may install an LVDT with a serial number listed in the “Affected Serial Numbers” table in Figure 1 of Boeing Alert Service Bulletin DC10-22A127, dated December 17, 2001, excluding Evaluation Form, on any airplane.

Alternative Methods of Compliance

(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, 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.

Note 3:

Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Los Angeles ACO.

Special Flight Permits

(d) Special flight permits may be issued in accordance with §§ 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.

Start Signature

Issued in Renton, Washington, on March 11, 2003.

Ali Bahrami,

Acting Manager, Transport Airplane Directorate, Aircraft Certification Service.

End Signature End Part End Supplemental Information

[FR Doc. 03-6258 Filed 3-14-03; 8:45 am]

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