2010-28080. Airworthiness Directives; McDonnell Douglas Corporation Model MD-90-30 Airplanes

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

We propose to adopt a new airworthiness directive (AD) for all McDonnell Douglas Model MD-90-30 airplanes. This proposed AD would require installing new fire handle shutoff system wiring. This proposed AD was prompted by a possible latent failure in the fire handle shutoff relay circuit due to a lack of separation between engine wires. We are proposing this AD to minimize the possibility of a multiple engine shutdown due to single fire handle activation.

DATES:

We must receive comments on this proposed AD by December 20, 2010.

ADDRESSES:

You may send comments by any of the following methods:

• Federal eRulemaking Portal: Go to http://www.regulations.gov. Follow the instructions for submitting comments.
• Fax: [phone].
• Mail: U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue, SE., Washington, DC 20590.
• Hand Delivery: Deliver to Mail address above between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays.

For service information identified in this proposed AD, contact Boeing Commercial Airplanes, Attention: Data & Services Management, 3855 Lakewood Boulevard, MC D800-0019, Long Beach, California 90846-0001; telephone [phone], extension 2; fax [phone]; e-mail [e-mail]; Internet https://www.myboeingfleet.com. You may review copies of the referenced service information at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington. For information on the availability of this material at the FAA, call 425-227-1221.

Examining the AD Docket

You may examine the AD docket on the Internet at http://www.regulations.gov;​; or in person at the Docket Management Facility between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD docket contains this proposed AD, the regulatory evaluation, any comments received, and other information. The street address for the Docket Office (phone: [phone]) is in the ADDRESSES section. Comments will be available in the AD docket shortly after receipt.

FOR FURTHER INFORMATION CONTACT:

William S. Bond, Aerospace Engineer, Los Angeles ACO—Propulsion Branch, ANM-140L, FAA Los Angeles Aircraft Certification Office, 3960 Paramount Blvd., Lakewood, CA 90712; telephone: [phone]; fax: [phone]; e-mail: [e-mail].

SUPPLEMENTARY INFORMATION:

Comments Invited

We invite you to send any written relevant data, views, or arguments about this proposal. Send your comments to an address listed under the ADDRESSES section. Include “Docket No. FAA-2010-1043; Directorate Identifier 2010-NM-200-AD” at the beginning of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of this proposed AD. We will consider all comments received by the closing date and may amend this proposed AD because of those comments.

We will post all comments we receive, without change, to http://www.regulations.gov, including any personal information you provide. We will also post a report summarizing each substantive verbal contact we receive about this proposed AD.

Discussion

We have received a report from Boeing identifying a potential unsafe condition. The engine fire shutoff handles on the MD-90 airplanes are designed to shutoff fuel at both the wing spar's mechanical fuel fire shutoff valve and the electrical solenoid controlled engine fuel shutoff valve in the engine Hydromechanical Unit (HMU). Due to the lack of separation between engine wires, a latent failure in the fire handle fuel shutoff relay circuit has the potential of causing a dual engine shutdown in the event any single engine fuel fire shutoff handle is activated. Separating the fire handle shutoff system wiring will minimize the possibility of multiple engine shutdown due to a single event. This condition, if not corrected, has the potential of causing a dual engine shutdown in the event of any single engine fuel fire shutoff handle activation.

Relevant Service Information

We reviewed Boeing Alert Service Bulletin MD90-74A002, dated August 17, 2010. The service information describes procedures for installing new fire handle shutoff system wiring.

FAA's Determination

We are proposing this AD because we evaluated all the relevant information and determined the unsafe condition described previously is likely to exist or develop in other products of the same type design.

Proposed AD Requirements

This proposed AD would require accomplishing the actions specified in the service information described previously.

Costs of Compliance

We estimate that this proposed AD will affect 25 airplanes of U.S. registry.

We estimate the following costs to comply with this proposed AD:

Estimated Costs

Action	Labor cost	Parts cost	Cost per product	Cost on U.S. operators
Wiring change	8 work-hour × $85 per hour = $680	$489	$1,169	$29,225

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 determined that this proposed AD would not have federalism implications under Executive Order 13132. This proposed AD 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.

For the reasons discussed above, I certify 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),

(3) Will not affect intrastate aviation in Alaska, and

(4) 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.

List of Subjects in 14 CFR Part 39

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

The Proposed Amendment

Accordingly, under the authority delegated to me by the Administrator, the FAA proposes to amend 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 FAA amends § 39.13 by adding the following new airworthiness directive (AD):

McDonnell Douglas Corporation: Docket No. FAA-2010-1043; Directorate Identifier 2010-NM-200-AD.

Comments Due Date

(a) We must receive comments by December 20, 2010.

Affected ADs

(b) None.

Applicability

(c) This AD applies to all McDonnell Douglas Corporation Model MD-90-30 airplanes, certificated in any category.

Subject

(d) Joint Aircraft System Component (JASC)/Air Transport Association (ATA) of America Code 74: Ignition system.

Unsafe Condition

(e) This AD was prompted by a possible latent failure in the fire handle shutoff relay circuit due to a lack of separation between engine wires. We are proposing this AD to minimize the possibility of a multiple engine shutdown due to single fire handle activation.

Compliance

(f) Comply with this AD within the compliance times specified, unless already done.

Wire Installation

(g) Within 4,200 flight hours after the effective date of this AD, install new fire handle shutoff system wiring, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin MD90-74A002, dated August 17, 2010.

Alternative Methods of Compliance (AMOCs)

(h)(1) The Manager, Los Angeles Aircraft Certification Office, FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. In accordance with 14 CFR 39.19, send your request to your principal inspector or local Flight Standards District Office, as appropriate. If sending information directly to the manager of the ACO, send it to the attention of the person identified in the Related Information section of this AD.

(2) Before using any approved AMOC, notify your Principal Maintenance Inspector or Principal Avionics Inspector, as appropriate, or lacking a principal inspector, your local Flight Standards District Office.

Related Information

(i) For more information about this AD, contact William S. Bond, Aerospace Engineer, Los Angeles ACO—Airframe Branch, ANM-140L, FAA Los Angeles Aircraft Certification Office, 3960 Paramount Blvd, Lakewood, CA 90712-4137; telephone: [phone]; fax: [phone]; e-mail: [e-mail].

(j) For service information identified in this AD, contact Boeing Commercial Airplanes, Attention: Data & Services Management, 3855 Lakewood Boulevard, MC D800-0019, Long Beach, California 90846-0001; telephone [phone], extension 2; fax [phone]; e-mail [e-mail]; Internet https://www.myboeingfleet.com. You may review copies of the referenced service information at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington. For information on the availability of this material at the FAA, call 425-227-1221.

Issued in Renton, Washington, on October 21, 2010.

Michael Kaszycki,

Acting Manager, Transport Airplane Directorate, Aircraft Certification Service.