2010-15653. Airworthiness Directives; McDonnell Douglas Corporation Model DC-10-30, DC-10-30F, DC-10-30F (KC-10A and KDC-10), DC-10-40, DC-10-40F, and MD-10-30F Airplanes

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

We propose to adopt a new airworthiness directive (AD) for certain Model DC-10-30, DC-10-30F, DC-10-30F (KC-10A and KDC-10), DC-10-40, DC10-40F, and MD-10-30F airplanes. This proposed AD would require doing a one-time inspection of the wire bundles to determine if wires touch the upper surface of the center upper auxiliary fuel tank, and marking the location if necessary; a one-time inspection for splices and damage of all wire bundles routed above the center upper auxiliary fuel tank; a one-time inspection for damage to the fuel vapor barrier seal and upper surface of the center upper auxiliary fuel tank; and corrective actions, if necessary. This proposed AD would also require installing non-metallic barrier/shield sleeving to the wire harnesses, new clamps, new attaching hardware, and new extruded channels. This proposed AD results from fuel system reviews conducted by the manufacturer. We are proposing this AD to prevent the potential of ignition sources inside fuel tanks, which, in combination with flammable fuel vapors, could result in fuel tank explosions and consequent loss of the airplane.

DATES:

We must receive comments on this proposed AD by August 12, 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: U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue, SE., Washington, DC 20590, 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 (telephone [phone]) is in the ADDRESSES section. Comments will be available in the AD docket shortly after receipt.

FOR FURTHER INFORMATION CONTACT:

Samuel Lee, 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:

Comments Invited

We invite you to send any written relevant data, views, or arguments about this proposed AD. Send your comments to an address listed under the ADDRESSES section. Include “Docket No. FAA-2010-0553; Directorate Identifier 2010-NM-070-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

The FAA has examined the underlying safety issues involved in fuel tank explosions on several large transport airplanes, including the adequacy of existing regulations, the service history of airplanes subject to those regulations, and existing maintenance practices for fuel tank systems. As a result of those findings, we issued a regulation titled “Transport Airplane Fuel Tank System Design Review, Flammability Reduction and Maintenance and Inspection Requirements” (66 FR 23086, May 7, 2001). In addition to new airworthiness standards for transport airplanes and new maintenance requirements, this rule included Special Federal Aviation Regulation No. 88 (“SFAR 88,” Amendment 21-78, and subsequent Amendments 21-82 and 21-83).

Among other actions, SFAR 88 requires certain type design (i.e., type certificate (TC) and supplemental type certificate (STC)) holders to substantiate that their fuel tank systems can prevent ignition sources in the fuel tanks. This requirement applies to type design holders for large turbine-powered transport airplanes and for subsequent modifications to those airplanes. It requires them to perform design reviews and to develop design changes and maintenance procedures if their designs do not meet the new fuel tank safety standards. As explained in the preamble to the rule, we intended to adopt airworthiness directives to mandate any changes found necessary to address unsafe conditions identified as a result of these reviews.

In evaluating these design reviews, we have established four criteria intended to define the unsafe conditions associated with fuel tank systems that require corrective actions. The percentage of operating time during which fuel tanks are exposed to flammable conditions is one of these criteria. The other three criteria address the failure types under evaluation: Single failures, single failures in combination with a latent condition(s), and in-service failure experience. For all four criteria, the evaluations included consideration of previous actions taken that may mitigate the need for further action.

We have determined that the actions identified in this AD are necessary to reduce the potential of ignition sources inside fuel tanks, which, in combination with flammable fuel vapors, could result in fuel tank explosions and consequent loss of the airplane.

Fuel system reviews conducted by the manufacturer have determined that wires routed above the center upper auxiliary fuel tank are in close proximity to the upper surface of the tank. In addition, some wire harness mounts may have loosened, allowing the wires to contact the tank. This condition can cause wire damage or chafing that could lead to possible arcing and sparking on the fuel tank upper surface. If not corrected, wires in contact with the fuel tank could become damaged, and the possible resulting arcing and sparking could lead to burn-through of the upper surface of the fuel tank.

Relevant Service Information

We have reviewed Boeing Service Bulletin DC10-28-244, dated February 25, 2010. The service bulletin describes procedures for the following actions.

• Doing a one-time general visual inspection of the wire bundles to determine if wires touch the upper surface of the center upper auxiliary fuel tank, and marking the location(s) where the wire bundle(s) contacts the upper surface of the center upper auxiliary fuel tank.
• Doing a one-time detailed inspection of all wire bundles routed above the center upper auxiliary fuel tank for splices and damage (such as wire chafing, arcing, or broken insulation or burn marks), and corrective actions, which include repairing or replacing damaged wires, and relocating any splice; and repairing or replacing wires causing damage.
• Doing a one-time detailed inspection for damage (burn marks) on the upper surface of the center upper auxiliary fuel tank and fuel vapor barrier seal, and doing corrective actions, which include repairing the vapor barrier seal, and contacting Boeing for repair instructions and doing the repair.
• Installing non-metallic barrier/shield sleeving to the wire harnesses, new clamps, new attaching hardware, and new extruded channels to raise the wire harnesses off the upper surface of the center upper auxiliary fuel tank.

FAA's Determination and Requirements of This Proposed AD

We are proposing this AD because we evaluated all relevant information and determined the unsafe condition described previously is likely to exist or develop in other products of these same type designs. This proposed AD would require accomplishing the actions specified in the service information described previously.

Costs of Compliance

We estimate that this proposed AD would affect 166 airplanes of U.S. registry. The following table provides the estimated costs for U.S. operators to comply with this proposed AD.

Table—Estimated Costs

Inspection and installation	Work hours	Average labor rate per hour	Parts	Cost per product	Number of U.S.-registered airplanes	Fleet cost
Group 1 Inspection	16	$85	$0	$1,360	75	$102,000
Group 1 Installation	200	85	13,309	30,309	75	2,273,175
Group 2 Inspection	16	85	0	1,360	58	78,880
Group 2 Installation	232	85	16,660	36,380	58	2,110,040
Group 3 Inspection	16	85	0	1,360	18	24,480
Group 3 Installation	200	85	12,258	29,258	18	526,644
Group 4 Inspection	16	85	0	1,360	15	20,400
Group 4 Installation	200	85	12,372	29,372	15	440,580

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), 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.

You can find our regulatory evaluation and the estimated costs of compliance in the AD Docket.

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 AD:

McDonnell Douglas Corporation: Docket No. FAA-2010-0553; Directorate Identifier 2010-NM-070-AD.

Comments Due Date

(a) We must receive comments by August 12, 2010.

Affected ADs

(b) None.

Applicability

(c) This AD applies to McDonnell Douglas Corporation Model DC-10-30, DC-10-30F, DC-10-30F (KC-10A and KDC-10), DC-10-40, DC10-40F, and MD-10-30F airplanes, certificated in any category; as specified in Boeing Service Bulletin DC10-28-244, dated February 25, 2010.

Subject

(d) Air Transport Association (ATA) of America Code 28: Fuel.

Unsafe Condition

(e) This AD results from fuel system reviews conducted by the manufacturer. The Federal Aviation Administration is issuing this AD to reduce the potential of ignition sources inside fuel tanks, which, in combination with flammable fuel vapors, could result in fuel tank explosions and consequent loss of the airplane.

Compliance

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

Actions

(g) Within 60 months after the effective date of this AD do the actions specified in paragraphs (g)(1), (g)(2), (g)(3), and (g)(4) of this AD, as applicable, and do all applicable corrective actions, in accordance with the Accomplishment Instructions of Boeing Service Bulletin DC10-28-244, dated February 25, 2010, except as required by paragraph (h) of this AD. Do all applicable corrective actions before further flight.

(1) Do a one-time general visual inspection of the wire bundles to determine if wires touch the upper surface of the center upper auxiliary fuel tank, and mark the location as applicable.

(2) Do a one-time detailed inspection for splices and damage of all wire bundles between Stations Y=1219.000 and Y=1381.000 between X=−40 to X=−90 (right side) and X=15 to X=85 (left side) above the center upper auxiliary fuel tank.

(3) Do a one-time detailed inspection for damage (burn marks) on the upper surface of the center upper auxiliary fuel tank and to the fuel vapor barrier seal.

(4) Install non-metallic barrier/shield sleeving to the wire harnesses, new clamps, new attaching hardware, and new extruded channels.

(h) Where Boeing Service Bulletin DC10-28-244, dated February 25, 2010, specifies to contact Boeing for repair instructions: Before further flight, repair the center upper auxiliary fuel tank using a method approved in accordance with the procedures specified in paragraph (i) of this AD.

Alternative Methods of Compliance (AMOCs)

(i)(1) The Manager, Los Angeles Aircraft Certification Office (ACO), FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. Send information to ATTN: Samuel Lee, Aerospace Engineer, Propulsion Branch, ANM-140L, FAA, Los Angeles ACO, 3960 Paramount Boulevard, Lakewood, California 90712-4137; telephone [phone]; fax [phone].

(2) To request a different method of compliance or a different compliance time for this AD, follow the procedures in 14 CFR 39.19. Before using any approved AMOC on any airplane to which the AMOC applies, notify your principal maintenance inspector (PMI) or principal avionics inspector (PAI), as appropriate, or lacking a principal inspector, your local Flight Standards District Office. The AMOC approval letter must specifically reference this AD.

(3) An AMOC that provides an acceptable level of safety may be used for any repair required by this AD if it is approved by the Boeing Commercial Airplanes Organization Designation Authorization (ODA) that has been authorized by the Manager, Los Angeles ACO to make those findings. For a repair method to be approved, the repair must meet the certification basis of the airplane and the approval must specifically refer to this AD.

Issued in Renton, Washington, on June 16, 2010.

Robert D. Breneman,

Acting Manager, Transport Airplane Directorate, Aircraft Certification Service.