E6-14289. Airworthiness Directives; McDonnell Douglas Model DC-9-10, -20, -30, -40, and -50 Series Airplanes

AGENCY:

Federal Aviation Administration (FAA), Department of Transportation (DOT).

ACTION:

Final rule.

SUMMARY:

The FAA is adopting a new airworthiness directive (AD) for all McDonnell Douglas Model DC-9-10, -20, -30, -40, and -50 series airplanes. This AD requires replacing the clamp bases for the fuel vent pipe with improved clamp bases. This AD results from reports that the foil wrapping on existing plastic clamp bases has migrated out of position, which compromises the bonding of the fuel vent lines to the airplane structure. We are issuing this AD to ensure that the fuel vent lines are properly bonded to the airplane structure. Improper bonding could prevent electrical energy from a lightning strike from dissipating to the airplane structure, and create an ignition source, which could result in a fuel tank explosion.

DATES:

This AD becomes effective October 4, 2006.

The Director of the Federal Register approved the incorporation by reference of a certain publication listed in the AD as of October 4, 2006.

ADDRESSES:

You may examine the AD docket on the Internet at http://dms.dot.gov or in person at the Docket Management Facility, U.S. Department of Transportation, 400 Seventh Street, SW., Nassif Building, Room PL-401, Washington, DC.

Contact Boeing Commercial Airplanes, Long Beach Division, 3855 Lakewood Boulevard, Long Beach, California 90846, Attention: Data and Service Management, Dept. C1-L5A (D800-0024), for service information identified in this AD.

FOR FURTHER INFORMATION CONTACT:

Serj Harutunian, Aerospace Engineer, Propulsion Branch, ANM-140L, FAA, Los Angeles Aircraft Certification Office, 3960 Paramount Boulevard, Lakewood, California 90712-4137; telephone [phone]; fax [phone].

SUPPLEMENTARY INFORMATION:

Examining the Docket

You may examine the airworthiness directive (AD) docket on the Internet at http://dms.dot.gov or in person at the Docket Management Facility office between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The Docket Management Facility office (telephone [phone]) is located on the plaza level of the Nassif Building at the street address stated in the ADDRESSES section.

Discussion

The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 to include an AD that would apply to all McDonnell Douglas Model DC-9-10, -20, -30, -40, and -50 series airplanes. That NPRM was published in the Federal Register on April 11, 2006 (71 FR 18249). That NPRM proposed to require replacing the clamp bases for the fuel vent pipe with improved clamp bases.

New Relevant Service Information

Since we issued the NPRM, Boeing has issued Service Bulletin DC9-28-211, Revision 1, dated June 21, 2006. (The NPRM referred to the original issue of that service bulletin, dated February 23, 2005, as the appropriate source of service information for the replacement of the clamp bases.) The instructions in Revision 1 are essentially the same as those in the original issue of the service bulletin. Among other things, Revision 1 of the service bulletin reduces the recommended compliance time from 10 years to 5 years, and revises the cost of parts. The NPRM specified a compliance time of 60 months, so no change to the compliance time in this AD is needed. We have, however, revised the Costs of Compliance section of this AD to reflect the increased parts cost. We have also added a new paragraph (g) to give credit for actions accomplished before the effective date of this AD in accordance with the original issue of the service bulletin, and re-identified subsequent paragraphs accordingly.

Comments

We provided the public the opportunity to participate in the development of this AD. We have considered the comments received.

Request To Extend Compliance Time

The Air Transport Association, on behalf of its member Northwest Airlines (NWA), agrees with the intent of the NPRM. However, NWA notes that the proposed 60-month compliance time is significantly less than the 10-year compliance time recommended in the original issue of Boeing Service Bulletin DC9-28-211. NWA states that its current maintenance program necessitates gaining access to the outboard fuel tanks every 9 years. NWA notes that the 60-month compliance time would necessitate additional work hours and more out-of-service time.

We infer that NWA is requesting that we extend the compliance time to agree with the original issue of the Boeing service bulletin. We do not agree that any change is necessary. In developing an appropriate compliance time for this AD, we considered not only the manufacturer's recommendation, but also the degree of urgency associated with the subject unsafe condition and the average utilization of the affected fleet. In light of all of these factors, we have determined that a 60-month compliance time represents an appropriate interval of time for affected airplanes to continue to operate without compromising safety. Further, we note that the 60-month compliance time is consistent with the recommended 5-year compliance time specified in Revision 1 of Boeing Service Bulletin DC9-28-211. We have not changed the AD in this regard.

Request To Revise Costs of Compliance

Boeing comments that the service bulletin estimates that it will take 8 work hours to do the actions therein, but the NPRM estimates 4 work hours are needed to do the proposed actions.

We infer that Boeing is requesting that we revise the Costs of Compliance section to reflect the 8-work-hour estimate in the service bulletin. We do not agree. The cost information below describes only the direct costs of the specific actions required by this AD. The estimate of 4 work hours represents the time necessary to perform only the actions actually required by this AD. The cost analysis in AD rulemaking actions typically does not include incidental costs such as the time required to gain access and close up, time necessary for planning, or time necessitated by other administrative actions. We recognize that, in doing the actions required by an AD, operators may incur incidental costs in addition to the direct costs. Those incidental costs, which may vary significantly among operators, are almost impossible to calculate. We have not changed the AD in this regard.

Conclusion

We have carefully reviewed the available data, including the comments received, and determined that air safety and the public interest require adopting the AD with the changes described previously. We have determined that these changes will neither increase the economic burden on any operator nor increase the scope of the AD.

Costs of Compliance

There are about 640 airplanes of the affected design in the worldwide fleet. This AD affects about 413 airplanes of U.S. registry. The required actions will take up to 4 work hours per airplane, at an average labor rate of $80 per work hour. Required parts will cost between $1,034 and $2,068 per airplane. Based on these figures, the estimated cost of this AD for U.S. operators is between $559,202 and $986,244, or $1,354 and $2,388 per airplane.

Authority for This Rulemaking

Title 49 of the United States Code specifies the FAA's authority to issue rules on aviation safety. Subtitle I, Section 106, describes the authority of the FAA Administrator. Subtitle VII, Aviation Programs, describes in more detail the scope of the Agency's authority.

We are issuing this rulemaking under the authority described in Subtitle VII, Part A, Subpart III, Section 44701, “General requirements.” Under that section, Congress charges the FAA with promoting safe flight of civil aircraft in air commerce by prescribing regulations for practices, methods, and procedures the Administrator finds necessary for safety in air commerce. This regulation is within the scope of that authority because it addresses an unsafe condition that is likely to exist or develop on products identified in this rulemaking action.

Regulatory Findings

We have determined that this AD will not have federalism implications under Executive Order 13132. This AD will 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.

For the reasons discussed above, I certify that this AD:

(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.

We prepared a regulatory evaluation of the estimated costs to comply with this AD and placed it in the AD docket. See the ADDRESSES section for a location to examine the regulatory evaluation.

List of Subjects in 14 CFR Part 39

• Air transportation
• Aircraft
• Aviation safety
• Incorporation by reference
• Safety

Adoption of the Amendment

Accordingly, under the authority delegated to me by the Administrator, the FAA amends 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.

§ 39.13

[Amended]

2. The Federal Aviation Administration (FAA) amends § 39.13 by adding the following new airworthiness directive (AD):

2006-18-02 McDonnell Douglas: Amendment 39-14740. Docket No. FAA-2006-24368; Directorate Identifier 2005-NM-230-AD.

Effective Date

(a) This AD becomes effective October 4, 2006.

Affected ADs

(b) None.

Applicability

(c) This AD applies to all McDonnell Douglas Model DC-9-11, DC-9-12, DC-9-13, DC-9-14, DC-9-15, DC-9-15F, DC-9-21, DC-9-31, DC-9-32, DC-9-32 (VC-9C), DC-9-32F, DC-9-32F (C-9A, C-9B), DC-9-33F, DC-9-34, DC-9-34F, DC-9-41, and DC-9-51 airplanes, certificated in any category.

Unsafe Condition

(d) This AD results from reports that the foil wrapping on existing plastic clamp bases has migrated out of position, which compromises the bonding of the fuel vent lines to the airplane structure. We are issuing this AD to ensure that the fuel vent lines are properly bonded to the airplane structure. Improper bonding could prevent electrical energy from a lightning strike from dissipating to the airplane structure, and create an ignition source, which could result in a fuel tank explosion.

Compliance

(e) You are responsible for having the actions required by this AD performed within the compliance times specified, unless the actions have already been done.

Clamp Base Replacement

(f) Within 60 months after the effective date of this AD, replace the existing clamp bases for the fuel vent line with improved metal clamp bases, by doing all of the applicable actions in accordance with the Accomplishment Instructions of Boeing Service Bulletin DC9-28-211, Revision 1, dated June 21, 2006. Any corrective action that is required following the conductivity verification, which is included in the replacement procedures, must be done before further flight.

Replacement Accomplished in Accordance With Previous Issue of Service Bulletin

(g) Replacement of clamp bases accomplished before the effective date of this AD in accordance with Boeing Service Bulletin DC9-28-211, dated February 23, 2005, is acceptable for compliance with the corresponding action required by paragraph (f) of this AD.

Alternative Methods of Compliance (AMOCs)

(h)(1) The Manager, Los Angeles Aircraft Certification Office (ACO), FAA, has the authority to approve AMOCs for this AD, if requested in accordance with the procedures found in 14 CFR 39.19.

(2) Before using any AMOC approved in accordance with § 39.19 on any airplane to which the AMOC applies, notify the appropriate principal inspector in the FAA Flight Standards Certificate Holding District Office.

Material Incorporated by Reference

(i) You must use Boeing Service Bulletin DC9-28-211, Revision 1, dated June 21, 2006, to perform the actions that are required by this AD, unless the AD specifies otherwise. The Director of the Federal Register approved the incorporation by reference of this document in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Contact Boeing Commercial Airplanes, Long Beach Division, 3855 Lakewood Boulevard, Long Beach, California 90846, Attention: Data and Service Management, Dept. C1-L5A (D800-0024), for a copy of this service information. You may review copies at the Docket Management Facility, U.S. Department of Transportation, 400 Seventh Street SW., Room PL-401, Nassif Building, Washington, DC; on the Internet at http://dms.dot.gov; or at the National Archives and Records Administration (NARA). For information on the availability of this material at the NARA, call [phone], or go to http://www.archives.gov/​federal_​register/​code_​of_​federal_​regulations/​ibr_​locations.html.

Issued in Renton, Washington, on August 18, 2006.

Kalene C. Yanamura,

Acting Manager, Transport Airplane Directorate, Aircraft Certification Service.