E9-20994. Airworthiness Directives; 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, DC-10-40F, MD-10-10F, and MD-10-30F Airplanes

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Supplemental notice of proposed rulemaking (NPRM); reopening of comment period.

SUMMARY:

We are revising an earlier proposed airworthiness directive (AD) for 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, DC-10-40F, MD-10-10F, and MD-10-30F airplanes. That action (the first supplemental NPRM) would have superseded an existing AD that currently requires installing or replacing with improved parts, as applicable, the bonding straps between the metallic frame of the fillet and the wing leading edge ribs, on both the left and right sides of the airplane. The first supplemental NPRM proposed to add a requirement to reposition or replace two bonding straps for certain airplanes. This action resulted from fuel system reviews conducted by the manufacturer. This second supplemental NPRM would add, for certain airplanes, a bonding-resistance check and an inspection to determine correct installation of certain bonding straps, and applicable corrective actions. We are proposing this second supplemental NPRM to reduce the potential of ignition sources inside fuel tanks in the event of a severe lightning strike, 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 supplemental NPRM by September 28, 2009.

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 or 425-227-1152.

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-2007-0186; Directorate Identifier 2007-NM-226-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 issued a notice of proposed rulemaking (NPRM) (the “first supplemental NPRM”) to amend 14 CFR part 39 to include an airworthiness directive (AD) that would apply 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, DC-10-40F, MD-10-10F, and MD-10-30F airplanes. The first supplemental NPRM was published in the Federal Register on November 26, 2008 (73 FR 71957).

The first supplemental NPRM would have superseded an existing AD that currently requires installing or replacing with improved parts, as applicable, the bonding straps between the metallic frame of the fillet and the wing leading edge ribs, on both the left and right sides of the airplane. The first supplemental NPRM proposed to add a requirement to reposition or replace two bonding straps for certain airplanes.

Actions Since First Supplemental NPRM Was Issued

Since we issued the first supplemental NPRM, Boeing has issued Service Bulletin DC10-53-109, Revision 7, dated March 3, 2009; and Service Bulletin DC10-53-111, Revision 6, dated March 3, 2009. We cited Boeing Service Bulletin DC10-53-109, Revision 6, dated July 10, 2008; and Boeing Service Bulletin DC10-53-111, Revision 5, dated March 19, 2008; in the first supplemental NPRM. The newly revised service bulletins contain the same procedures as the earlier revisions along with the following changes:

• Boeing Service Bulletin DC10-53-109, Revision 7, dated March 3, 2009, provides instructions to measure the electrical resistance of certain previously installed braided bonding straps and correct any failed resistance checks. The corrective action includes cleaning and installing the braided bonding strap assembly.
• Boeing Service Bulletin DC10-53-111, Revision 6, dated March 3, 2009, incorporates comments from operators to clarify service bulletin instructions, including instructions for Group 1-2 airplanes, Configuration 2, to check the electrical resistance for bonding straps previously installed and correct any failed resistance checks. The corrective action includes cleaning and installing the braided bonding strap assembly. This service bulletin also includes an inspection to determine correct installation of braided bonding straps, and corrective action if necessary, for Group 1-2 airplanes, Configuration 2. The corrective action is repositioning braided bonding straps and replacing fasteners.

We have also approved the revised service bulletins as alternative methods of compliance (AMOCs) for the requirements of AD 2006-16-03.

Comments

We gave the public the opportunity to participate in developing this AD. We considered the comments received from the sole commenter, FedEx Express (FedEx).

Support for the NPRM

FedEx applauds the FAA's decision to include “AMOCs approved previously in accordance with AD 2006-16-03 * * * as AMOCs for the corresponding provisions of this AD.” This statement allows FedEx to use its previously obtained AMOC, dated May 24, 2007, for compliance with the bulk of the proposed requirements, without the need for additional FAA approval. Any additional work required by the AD can be incorporated into FedEx's existing modification program using the AD as approval.

Request To Provide Additional Information

FedEx requests that the section of the first supplemental NPRM titled “Actions Since Original NPRM Was Issued” include the following statement: “[Boeing] Service Bulletin DC10-53-109, Revision 5, now includes an action to reposition two bonding straps by using new bonding straps that are less susceptible to cracking.” FedEx notes that while this statement comes directly from the service bulletin section titled “Reason for Revision,” an examination of the changes to Boeing Service Bulletin DC10-53-109, Revision 5, dated March 19, 2008, indicates that the straps in question, which were installed according to McDonnell Douglas DC-10 Service Bulletin 53-109, Revision 4, dated October 7, 1992, are identical to the straps that replace them in Revision 5, except the replacement straps are 2 inches longer. Revision 6, dated July 10, 2008, of this service bulletin corrects the previous statement in the “Reason” section as follows: “Revision 5 was sent to incorporate engineering released subsequent to Revision 4 of this service bulletin, which replaces an existing braided bonding strap (each side) with a new longer braided bonding strap that is less susceptible to chafing structure.”

To avoid confusion, FedEx requests that we revise corresponding language in the AD to something similar to the following: “[Boeing] Service Bulletin DC10-53-109, Revision 5, now includes an action to remove and replace two bonding straps installed via Revision 4 of the service bulletin with longer bonding straps.”

We acknowledge FedEx's concern that this language may be confusing. However, the section of the AD preamble referenced by the commenter does not appear in this second supplemental NPRM. In addition, as stated previously, this second supplemental NPRM refers to Revision 7 of Boeing Service Bulletin DC10-53-109, dated March 3, 2009, which contains the correct information in regard to this issue.

Request To Change “Reason for Revision”

FedEx requests that we revise the reason for using Boeing Service Bulletin DC10-53-109, Revision 6, dated July 10, 2008, in the first supplemental NPRM to read “Revision 6 of Service Bulletin DC10-53-109 provides a faster and easier method of replacing the two bonding straps that require replacement per Revision 5, and corrects some part number errors.” FedEx also suggests that we revise the reason for using Boeing Service Bulletin DC10-53-111, Revision 5, dated March 19, 2008, as noted in the first supplemental NPRM, to read “In addition to the effectivity correction, Revision 5 of Service Bulletin DC10-53-111 requires the repositioning of two braided bonding straps installed on certain aircraft configuration via Revision 4 and all configurations via Service Bulletin revisions released prior to Revision 4.”

We acknowledge FedEx's suggestions that the prior revisions of the service bulletins need to be clarified. However, the section of the AD preamble referenced by the commenter does not appear in this second supplemental NPRM. In addition, this second supplemental NPRM refers to Boeing Service Bulletin DC10-53-109, Revision 7, dated March 3, 2009; and Boeing Service Bulletin DC10-53-111, Revision 6, dated March 3, 2009; which contain the correct information in regard to this issue.

Request To Revise Paragraph (h) of the First Supplemental NPRM

FedEx requests that we revise paragraph (h) of the first supplemental NPRM to indicate that the action is to “remove two braided bonding straps and install two longer braided bonding straps between the metallic frame of the fillet and the wing leading edge ribs” in lieu of “reposition two bonding straps.”

We concur with FedEx, and the requested changes in paragraph (h) of the first supplemental NPRM are incorporated in the new reidentified paragraph (i)(1) of this second supplemental NPRM.

In addition, FedEx believes that additional work is required for all airplanes previously modified in accordance with McDonnell Douglas DC-10 Service Bulletin 53-109, Revision 4, dated October 7, 1992.

We agree with FedEx's request to provide clarification. Airplanes that were modified in accordance with McDonnell Douglas DC-10 Service Bulletin 53-109, Revision 4, dated October 7, 1992, also require an electrical resistance measurement of previously installed braided bonding straps to be in compliance with the proposed requirements of this second supplemental NPRM. Revision 7 of McDonnell Douglas DC-10 Service Bulletin 53-109, dated March 3, 2009, clarifies the additional work required. We have revised paragraph (h) of the first supplemental NPRM (now paragraph (i) of this second supplmenetal NPRM) to specify the additional work required and that the additional work be accomplished in accordance with McDonnell Douglas DC-10 Service Bulletin 53-109, Revision 7, dated March 3, 2009.

Request To Clarify Procedures in Service Bulletin DC10-53-111, Revision 5

FedEx notes the following issues in Boeing Service Bulletin DC10-53-111, Revision 5, dated March 19, 2008:

• In Figure 3, the requirement to remove and install all strap brackets should be removed. Only require a conductivity check of the previously installed strap (with the exception of the single strap that will need to be relocated) with any additional rework based on the results of the conductivity check. Also include the strap to fillet seal and encapsulate with sealant all strap attach points.
• The groups and configurations callouts should be revised to distinguish airplanes that did or did not receive metal bonding straps in production and distinguish those on which a previous version of Boeing Service Bulletin DC10-53-111 was or was not done.
• The fastener pattern in Figure 1 should be corrected by removing the middle rivet of the three rivets indicated by “2” in the figure and the rivet to the left of those three rivets. This would leave the figure with six evenly spaced rivets on the edge of the stiffener that receives the installation. It also makes the figure match the work instruction.
• The compliance section should be revised so that steps 6 through 13 of Figure 3 of Boeing Service Bulletin DC10-53-111, Revision 5, dated March 19, 2008, must be done on all airplanes that have been modified per Figures 1 or 2 of Boeing Service Bulletin DC10-53-111, Revision 4, dated September 21, 2006.

We infer that FedEx wants us to revise this second supplemental NPRM to provide the correct information. We agree. As stated previously, this second supplemental NPRM refers to Boeing Service Bulletin DC10-53-111, Revision 6, dated March 3, 2009, which contains the correct information in regard to these issues.

Request To Clarify Procedures in Service Bulletin DC10-53-109

FedEx requests the following clarifications of configurations and electrical bonding requirements in Boeing Service Bulletin DC10-53-109, Revision 6, dated July 10, 2008:

• Configuration 3 should apply only to airplanes previously accomplished per Boeing Service Bulletin DC10-53-109, Revision 5, dated March 19, 2008, instead of McDonnell Douglas DC-10 Service Bulletin 53-109, Revision 4, dated October 7, 1992.
• Configurations accomplished in accordance with McDonnell Douglas DC-10 Service Bulletin 53-109, Revision 1, dated August 14, 1981; McDonnell Douglas DC-10 Service Bulletin 53-109, Revision 2, dated October 28, 1983; McDonnell Douglas DC-10 Service Bulletin 53-109, Revision 3, dated November 14, 1986; and McDonnell Douglas DC-10 Service Bulletin 53-109, Revision 4, dated October 7, 1992; should each have their own specific configuration.

All previous braided straps are removed and reinstalled using proper electrical bonding procedures.

• All references to actions taken for Configuration 3 airplanes should refer to removing braided bonding straps and installing new, longer braided bonding straps.

We concur with FedEx's comments that the proper electrical bonding procedures and/or clarifications be provided in the associated Boeing service bulletins. As stated previously, this second supplemental NPRM now refers to Boeing Service Bulletin DC10-53-109, Revision 7, dated March 3, 2009, which contains instructions for conductivity checks for all previously installed braided bonding straps, as requested by FedEx. In addition, we note that Configuration 3 applies only to aircraft previously modified per McDonnell Douglas DC-10 Service Bulletin 53-109, Revision 4, dated October 7, 1992, of this service bulletin, not Boeing Service Bulletin DC10-53-109, Revision 5, dated March 19, 2008, as FedEx commented.

Explanation of Additional Paragraph in the Supplemental NPRM

We have added a new paragraph (d) to this supplemental NPRM to provide the Air Transport Association (ATA) of America code. This code is added to make this supplemental NPRM parallel with other new AD actions. We have reidentified subsequent paragraphs accordingly.

FAA's Determination and Proposed Requirements of the Supplemental NPRM

We are proposing this second supplemental NPRM because we evaluated all pertinent information and determined an unsafe condition exists and is likely to exist or develop on other products of the same type design. Certain changes described above expand the scope of the first supplemental NPRM. As a result, we have determined that it is necessary to reopen the comment period to provide additional opportunity for the public to comment on this second supplemental NPRM.

Costs of Compliance

We estimate that this proposed AD would affect 280 airplanes of U.S. registry. The following table provides the estimated costs for U.S. operators to comply with this proposed AD.

Estimated Costs

Work hours	Average labor rate per hour	Parts	Cost per product	Number of U.S.-registered airplanes	Fleet cost
2-17	$80	Up to $4,169	Up to $5,529	281	Up to $1,553,649.

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 removing amendment 39-14703 (71 FR 43962, August 3, 2006) and adding the following new AD:

McDonnell Douglas: Docket No. FAA-2007-0186; Directorate Identifier 2007-NM-226-AD.

Comments Due Date

(a) We must receive comments by September 28, 2009.

Affected ADs

(b) This AD supersedes AD 2006-16-03.

Applicability

(c) This AD applies to 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, and MD-10-10F and MD-10-30F airplanes that have been converted from Model DC-10 series airplanes; certificated in any category; with manufacturer's fuselage numbers as identified in the applicable service bulletin listed in Table 1 of this AD.

Table 1—Applicability

Boeing Service Bulletin—	Revision—	Dated—	For airplanes with—
DC10-53-109	7	March 3, 2009	Extended wing-to-fuselage fillets.
DC10-53-111	6	March 3, 2009	Conventional wing-to-fuselage fillets.

Subject

(d) Air Transport Association (ATA) of America Code 53: Fuselage.

Unsafe Condition

(e) This AD results from fuel system reviews conducted by the manufacturer. We are issuing this AD to reduce the potential of ignition sources inside fuel tanks in the event of a severe lightning strike, 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.

Restatement of Requirements of AD 2006-16-03 With New Service Information

Installation or Replacement

(g) For airplanes with manufacturer's fuselage numbers identified in the applicable service bulletin listed in Table 2 of this AD: Within 7,500 flight hours or 60 months after September 7, 2006 (the effective date of AD 2006-16-03), whichever occurs earlier: Install or replace with improved parts, as applicable, the bonding straps between the metallic frame of the fillet and the wing leading edge ribs, on both the left and right sides of the airplane, in accordance with the Accomplishment Instructions of the applicable service bulletin identified in Table 2 of this AD or Table 1 of this AD. After the effective date of this AD, use the applicable service bulletin identified in Table 1 of this AD.

Table 2—Fuselage Numbers Affected by AD 2006-16-03

McDonnell Douglas DC-10 Service Bulletin—	Revision—	Dated—	For airplanes with—
53-109	4	October 7, 1992	Extended wing-to-fuselage fillets.
53-111	3	August 24, 1992	Conventional wing-to-fuselage fillets.

New Requirements of This AD

Installation or Replacement

(h) For airplanes with fuselage numbers not identified in Table 2 of this AD except for airplanes identified in paragraph (i) or (j) of this AD: Within 7,500 flight hours or 60 months, whichever occurs first after the effective date of this AD, install or replace with improved parts, as applicable, the bonding straps between the metallic frame of the fillet and the wing leading edge ribs, on both the left and right sides of the airplane, and reposition two bonding straps. Do the actions in accordance with the Accomplishment Instructions of the applicable service bulletin identified in Table 1 of this AD.

Strap Repositioning for Certain Airplanes

(i) For Group 1-4, Configuration 3 airplanes, as identified in Boeing Service Bulletin DC10-53-109, Revision 7, dated March 3, 2009: Within 7,500 flight hours or 60 months after the effective date of this AD, whichever occurs first, do the actions specified in paragraphs (i)(1) and (i)(2) of this AD.

(1) Remove two braided bonding straps and install two longer braided bonding straps between the metallic frame of the fillet and the wing leading edge ribs, in accordance with the Accomplishment Instructions of Boeing Service Bulletin DC10-53-109, Revision 7, dated March 3, 2009.

(2) Measure the resistance of the previously installed bonding straps and, before further flight, do all applicable corrective actions in accordance with the Accomplishment Instructions of Boeing Service Bulletin DC10-53-109, Revision 7, dated March 3, 2009.

Inspection and Corrective Action for Certain Airplanes

(j) For Group 1-2, Configuration 2 airplanes, as identified in Boeing Service Bulletin DC10-53-111, Revision 6, dated March 3, 2009: Within 7,500 flight hours or 60 months after the effective date of this AD, whichever occurs first, do the actions specified in paragraphs (j)(1) and (j)(2) of this AD.

(1) Do a general visual inspection to verify correct installation of the braided bonding strap, and, before further flight, do all applicable corrective actions, in accordance with Accomplishment Instructions of Boeing Service Bulletin DC10-53-111, Revision 6, dated March 3, 2009.

(2) Measure the resistance of the previously installed bonding straps and, before further flight, do all applicable corrective actions, in accordance with Accomplishment Instructions of Boeing Service Bulletin DC10-53-111, Revision 6, dated March 3, 2009.

Credit for Actions Accomplished In Accordance With Previous Service Information

(k) Actions accomplished before the effective date of this AD according to Boeing Service Bulletin DC10-53-111, Revision 5, dated March 19, 2008; and Boeing Service Bulletin DC10-53-109, Revision 6, dated July 10, 2008; are considered acceptable for compliance with the corresponding action specified in this AD.

Alternative Methods of Compliance (AMOCs)

(l)(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 Aircraft Certification Office, 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) AMOCs approved previously in accordance with AD 2006-16-03 are approved as AMOCs for the corresponding provisions of this AD.

Issued in Renton, Washington, on August 17, 2009.

Ali Bahrami,

Manager, Transport Airplane Directorate, Aircraft Certification Service.