Airworthiness Directives; McDonnell Douglas Model DC-10 Series Airplanes, Model MD-10 Series Airplanes, and Model MD-11 Series Airplanes

AGENCY:

Federal Aviation Administration, DOT.

ACTION:

Final rule; rescission.

SUMMARY:

The FAA is rescinding an existing airworthiness directive (AD) that applies to certain McDonnell Douglas Model DC-10 series airplanes, Model MD-10 series airplanes, and Model MD-11 series airplanes. That AD requires repetitive inspections of the numbers 1 and 2 electric motors of the auxiliary hydraulic pump for electrical resistance, continuity, mechanical rotation, and associated wiring resistance/voltage; and corrective actions, if necessary. We issued that AD to prevent various failures of electric motors of the auxiliary hydraulic pump and associated wiring, which could result in fire at the auxiliary hydraulic pump and consequent damage to the adjacent electrical equipment and/or structure. Since we issued that AD, we have determined that the inspection requirements are identical to the inspection requirements of another existing AD.

DATES:

Effective September 1, 2004.

ADDRESSES:

Use one of the following addresses to submit comments on this rescission.

• DOT Docket Web site: Go to http://dms.dot.gov and follow the instructions for sending your comments electronically.
• Government-wide rulemaking Web site: Go to http://www.regulations.gov and follow the instructions for sending your comments electronically.
• Mail: Docket Management Facility; U.S. Department of Transportation, 400 Seventh Street, SW., Nassif Building, room PL-401, Washington, DC 20590.
• Fax: (202) 493-2251.
• Hand delivery: room PL-401 on the plaza level of the Nassif Building, 400 Seventh Street, SW., Washington, DC, between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays.

You can examine the contents of this AD docket on the Internet at http://dms.dot.gov,, or at the Docket Management Facility, U.S. Department of Transportation, 400 Seventh Street, SW., room PL-401, on the plaza level of the Nassif Building, Washington, DC.

FOR FURTHER INFORMATION CONTACT:

Ken Sujishi, Aerospace Engineer, Systems and Equipment Branch, ANM-130L, FAA, Los Angeles Aircraft Certification Office, 3960 Paramount Boulevard, Lakewood, California 90712-4137; telephone (562) 627-5353; fax (562) 627-5210.

SUPPLEMENTARY INFORMATION:

On July 2, 2001, the FAA issued AD 2001-14-08, amendment 39-12319 (66 FR 36441, July 12, 2001), which applies to certain McDonnell Douglas Model DC-10 series airplanes, Model MD-10 series airplanes, and Model MD-11 series airplanes. That AD requires repetitive inspections (at intervals not to exceed 6,000 flight hours) of the numbers 1 and 2 electric motors of the auxiliary hydraulic pump for electrical resistance, continuity, mechanical rotation, and associated wiring resistance/voltage; and corrective actions, if necessary. That action was prompted by reports that, during ground operations or when powered in flight by the air driven generator, the electric motors of the auxiliary hydraulic pump and associated motor feeder cables failed. The actions required by that AD are intended to prevent various failures of electric motors of the auxiliary hydraulic pump and associated wiring, which could result in fire at the auxiliary hydraulic pump and consequent damage to the adjacent electrical equipment and/or structure.

Actions Since Previous AD Was Issued

A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) to add a new airworthiness directive (AD), applicable to certain McDonnell Douglas Model DC-10-10, DC-10-10F, DC-10-15, DC-10-30, DC-10-30F (KC-10A, KDC-10), DC-10-40, and DC-10-40F airplanes; and Model MD-10-10F and MD-10-30F airplanes, was published in the Federal Register as a notice of proposed rulemaking (NPRM) on January 22, 2004 (69 FR 3036). The NPRM, Docket 2003-NM-119-AD, would supersede AD 2001-14-08 to require that the repetitive inspections of the numbers 1 and 2 electric motors of the auxiliary hydraulic pump for electrical resistance, continuity, mechanical rotation, and associated airplane wiring resistance/voltage; and corrective actions, if necessary, be performed at reduced intervals (i.e., from 6,000 flight hours to 2,500 flight hours). That action was prompted by a report from Boeing that the original compliance time was not adequate, because another incident of failure of an electric motor of the auxiliary hydraulic pump had occurred during the interval between repetitive inspections. The proposed actions are intended to prevent various failures of electric motors of the auxiliary hydraulic pump and associated wiring, which could result in fire at the auxiliary hydraulic pump and consequent damage to the adjacent electrical equipment and/or structure.

Since the issuance of AD 2001-14-08, we also issued AD 2004-05-20, amendment 39-13515 (69 FR 11504, March 11, 2004), applicable to certain McDonnell Douglas Model DC-10-10, DC-10-10F, DC-10-15, DC-10-30, DC-10-30F (KC-10A and KDC-10), DC-10-40, and DC-10-40F airplanes; Model MD-10-10F and MD-10-30F airplanes; and Model MD-11 and MD-11F airplanes. That AD requires modification of the installation wiring for the electric motor operated auxiliary hydraulic pumps in the right wheel well area of the main landing gear, and repetitive inspections (at intervals not to exceed 2,500 flight hours) of the numbers 1 and 2 electric motors of the auxiliary hydraulic pumps for electrical resistance, continuity, mechanical rotation, and associated airplane wiring resistance/voltage; and corrective actions if necessary. That action was prompted by several reports of failure of the auxiliary hydraulic pump systems. The requirements of that AD are intended to prevent failure of the electric motors of the hydraulic pump and associated wiring, which could result in fire at the auxiliary hydraulic pump and consequent damage to the adjacent electrical equipment and/or structure.

The repetitive inspections required by AD 2004-05-20 and proposed in NPRM, Docket 2003-NM-119-AD, are identical to those in AD 2001-14-08, but at different intervals. Accomplishment of the modification and the 2,500 flight-hour inspections requirements of AD 2004-05-20 adequately addresses the identified unsafe condition.

FAA's Determination

Upon further consideration, we have determined that we need to rescind AD 2001-14-08 to prevent operators from performing duplicate actions.

Since this action rescinds a requirement to perform a duplicate action, it has no adverse economic impact and imposes no additional burden on any person. Therefore, providing notice and opportunity for public comment is unnecessary before this AD is issued, and this AD may be made effective in less than 30 days after it is published in the Federal Register.

Other Relevant Rulemaking

For the reasons discussed previously, we are also planning to withdraw NPRM, Docket 2003-NM-119-AD, in a separate rulemaking action.

Comments Invited

Although this is a final rule that was not preceded by notice and an opportunity for public comment, we invite you to submit any written relevant data, views, or arguments regarding this AD. Send your comments to an address listed under ADDRESSES. Include “Docket No. FAA-2004-18978; Directorate Identifier 2004-NM-127-AD” at the beginning of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of the AD. We will consider all comments received by the closing date and may amend the AD in light of those comments.

We will post all comments we receive, without change, to http://dms.dot.gov,, including any personal information you provide. We will also post a report summarizing each substantive verbal contact with FAA personnel concerning this AD. Using the search function of our docket web site, anyone can find and read the comments in any of our dockets, including the name of the individual who sent the comment (or signed the comment on behalf of an association, business, labor union, etc.). You can review the DOT's complete Privacy Act Statement in the Federal Register published on April 11, 2000 (65 FR 19477-78), or you can visit http://dms.dot.gov.

We are reviewing the writing style we currently use in regulatory documents. We are interested in your comments on whether the style of this document is clear, and your suggestions to improve the clarity of our communications with you. You can get more information about plain language at http://www/faa.gov/language and http://www.plainlanguage.gov.

The Rescission

Accordingly, according to the authority delegated to me by the Administrator, the FAA amends part 39 of the Federal Aviation Regulations (14 CFR part 39) as follows:

PART 39—AIRWORTHINESS DIRECTIVES

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

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

2. Section 39.13 is amended by removing amendment 39-12319 ( 66 FR 36441, July 12, 2001).

2001-14-08 R1 McDonnell Douglas: Amendment 39-13780. Docket No. 2004-NM-127-AD.

Effective Date

(a) This AD becomes effective September 1, 2004.

Affected ADs

(b) This action rescinds AD 2001-14-08, Amendment 39-12319.

Applicability

(c) This action applies to Model DC-10 and MD-10 series airplanes, as listed in McDonnell Douglas Alert Service Bulletin DC10-29A142, Revision 01, dated October 21, 1999; and Model MD-11 series airplanes, as listed in McDonnell Douglas Alert Service Bulletin MD11-29A057, Revision 01, dated October 21, 1999; certificated in any category.