03-24680. Airworthiness Directives; McDonnell Douglas Model DC-10-10, DC-10-10F, DC-10-15, DC-10-30, DC-10-30F, DC-10-30F (KC-10A-and KDC-10), DC-10-40, DC-10-40F, MD-10-10F, and MD-10-30F Airplanes; and Model MD-11 and MD-11F Airplanes

AGENCY:

Federal Aviation Administration, DOT.

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

This document proposes the adoption of a new airworthiness directive (AD) that is applicable to certain McDonnell Douglas transport category airplanes. For certain airplanes, this proposal would require a general visual inspection to detect cracking in the nuts on the lower attach bolt assemblies of the forward attach bracket of the inboard flap outboard hinge, replacement of both upper and lower attach bolt assemblies with new bolts and nuts made from Inconel material, and replacement of certain preload-indicating (PLI) washers with new washers. For certain other airplanes, this proposal would require replacement of the lower attach bolt assemblies of the inboard forward attach bracket of the inboard flap outboard hinge with new bolts and nuts made from Inconel material, and replacement of PLI washers with new washers. These actions are necessary to prevent separation of the inboard flap outboard hinge from the wing structure and consequent reduced controllability of the airplane. This action is intended to address the identified unsafe condition.

DATES:

Comments must be received by November 14, 2003.

ADDRESSES:

Submit comments in triplicate to the Federal Aviation Administration (FAA), Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 2003-NM-43-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056. Comments may be inspected at this location between 9 a.m. and 3 p.m., Monday through Friday, except Federal holidays. Comments may be submitted via fax to [phone]. Comments may also be sent via the Internet using the following address: [e-mail]. Comments sent via fax or the Internet must contain “Docket No. 2003-NM-43-AD” in the subject line and need not be submitted in triplicate. Comments sent via the Internet as attached electronic files must be formatted in Microsoft Word 97 or 2000 or ASCII text.

The service information referenced in the proposed rule may be obtained from the Boeing Commercial Aircraft Group, Long Beach Division, 3855 Lakewood Boulevard, Long Beach, California 90846, Attention: Data and Service Management, Dept. C1-L5A (D800-0024). This information may be examined at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the FAA, Los Angeles Aircraft Certification Office, 3960 Paramount Boulevard, Lakewood, California.

FOR FURTHER INFORMATION CONTACT:

Ronald Atmur, Aerospace Engineer, Airframe Branch, ANM-120L, FAA, Los Angeles Aircraft Certification Office, 3960 Paramount Boulevard, Lakewood, California 90712-4137; telephone [phone]; fax [phone].

SUPPLEMENTARY INFORMATION:

Comments Invited

Interested persons are invited to participate in the making of the proposed rule by submitting such written data, views, or arguments as they may desire. Communications shall identify the Rules Docket number and be submitted in triplicate to the address specified above. All communications received on or before the closing date for comments, specified above, will be considered before taking action on the proposed rule. The proposals contained in this action may be changed in light of the comments received.Submit comments using the following format:

• Organize comments issue-by-issue. For example, discuss a request to change the compliance time and a request to change the service bulletin reference as two separate issues.
• For each issue, state what specific change to the proposed AD is being requested.
• Include justification (e.g., reasons or data) for each request.

Comments are specifically invited on the overall regulatory, economic, environmental, and energy aspects of the proposed rule. All comments submitted will be available, both before and after the closing date for comments, in the Rules Docket for examination by interested persons. A report summarizing each FAA-public contact concerned with the substance of this proposal will be filed in the Rules Docket.

Commenters wishing the FAA to acknowledge receipt of their comments submitted in response to this action must submit a self-addressed, stamped postcard on which the following statement is made: “Comments to Docket Number 2003-NM-43-AD.” The postcard will be date stamped and returned to the commenter.

Availability of NPRMs

Any person may obtain a copy of this NPRM by submitting a request to the FAA, Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 2003-NM-43-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056.

Discussion

The FAA received a report of an incident in June 2002, involving a McDonnell Douglas Model MD-11 airplane on which the left-hand inboard flap outboard hinge pulled away from the wing structure where a bracket attaches it with two upper and two lower bolts. Preliminary investigation indicated that the two lower attach bolt assemblies likely failed first. When the bracket separated, it caused an asymmetrical condition for the inboard flaps, additional structural damage to the wing, and loss of one hydraulic system. The flightcrew applied full right-hand aileron to level the wings, and during emergency landing, the tail of the airplane scraped the runway. The affected airplane had accumulated 37,439 flight-hours and 9,241 landings.

Following the incident reported above, on July 10, 2002, we issued AD 2002-14-03, amendment 39-12803 (67 FR 47254, July 18, 2002), which required, for certain MD-11 and MD-11F airplanes, a one-time inspection to detect loose PLI washers or cracked or corroded nuts of the lower bolts of the inboard flap outboard hinge, and replacement with new parts if necessary. As a result of the reporting requirements in AD 2002-14-03, it was determined that the failure in the affected bolts was due to stress corrosion. This condition, if not corrected, could result in separation of the inboard flap outboard hinge from the wing structure and consequent reduced controllability of the airplane.

The preamble to AD 2002-14-03, indicated that we consider the requirements “interim action,” and that we were considering further rulemaking. We have now determined that further rulemaking is indeed necessary, and this proposed AD follows from that determination.

Similar Models

The subject area on certain McDonnell Douglas Model DC-10-10, DC-10-10F, DC-10-15, DC-10-30, DC-10-30F, DC-10-30F (KC-10A- and KDC-10), DC-10-40, DC-10-40F, MD-10-10F, and MD-10-30F airplanes is almost identical to that on the affected Model MD-11 and MD-11F airplanes. Therefore, all of these models may be subject to the same unsafe condition.

Explanation of Relevant Service Information

The FAA has reviewed and approved Boeing Alert Service Bulletin DC10-57A149, including Appendices A and B, dated January 7, 2003, which describes procedures for performing a general visual inspection of lower attach bolt assembly nuts on the forward attach bracket of the inboard flap outboard hinge to detect cracking in the nuts. This service bulletin also describes procedures for replacing the upper and lower attach bolt assemblies with new bolts and nuts made from Inconel material, and for replacing certain PLI washers with new PLI washers.

The FAA has also reviewed and approved Boeing Alert Service Bulletin MD11-57A068, including Appendix A, dated January 7, 2003, which describes procedures for replacing the lower attach bolt assemblies on the forward attach bracket of the inboard flap outboard hinge with new bolts and nuts made from Inconel material and replacing the PLI washers with new PLI washers.

If the steel attach bolts assemblies were replaced previously with new Inconel material bolt assemblies, no further action is specified in the service bulletin. Accomplishment of the actions specified in the service bulletins is intended to adequately address the identified unsafe condition.

Explanation of Requirements of Proposed Rule

Since an unsafe condition has been identified that is likely to exist or develop on other products of this same type design, the proposed AD would require accomplishment of the actions specified in the service bulletins described previously. Although the Accomplishment Instructions in Boeing Alert Service Bulletin DC10-57A149, dated January 7, 2003, which is referenced in this proposed AD, specifies to submit information and discrepant parts to the manufacturer, this proposed AD does not include such a requirement.

Changes to 14 CFR part 39/Effect on the Proposed AD

On July 10, 2002, the FAA issued a new version of 14 CFR part 39 (67 FR 47997, July 22, 2002), which governs the FAA's airworthiness directives system. The regulation now includes material that relates to altered products, special flight permits, and alternative methods of compliance (AMOCs). Because we have now included this material in part 39, only the office authorized to approve AMOCs is identified in each individual AD.

Change to Labor Rate Estimate

We have reviewed the figures we have used over the past several years to calculate AD costs to operators. To account for various inflationary costs in the airline industry, we find it necessary to increase the labor rate used in these calculations from $60 per work hour to $65 per work hour. The cost impact information, below, reflects this increase in the specified hourly labor rate.

Cost Impact

There are approximately 394 Model DC-10 and Model MD-10 airplanes, and approximately 192 Model MD-11 and -11F airplanes of the affected design in the worldwide fleet. The FAA estimates that 252 DC-10 and Model MD-10 airplanes and 76 Model MD-11 and -11F airplanes of U.S. registry would be affected by this proposed AD, and that the average labor rate is $65 per hour.

The following table shows the estimated cost impact for airplanes affected by this proposed AD:

Table—Cost Impact Estimate

Model	Work hours	Labor cost per airplane	Parts cost per airplane	Fleet cost
DC-10 and MD-10 airplanes	25	$1,625	$4,139	$1,452,528
MD-11 and -11F airplanes	13	845	2,041	219,336

The cost impact figures discussed above are based on assumptions that no operator has yet accomplished any of the proposed requirements of this AD action, and that no operator would accomplish those actions in the future if this proposed AD were not adopted. The cost impact figures discussed in AD rulemaking actions represent only the time necessary to perform the specific actions actually required by the AD. These figures typically do not include incidental costs, such as the time required to gain access and close up, planning time, or time necessitated by other administrative actions.

Regulatory Impact

The regulations proposed herein 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. Therefore, it is determined that this proposal would not have federalism implications under Executive Order 13132.

For the reasons discussed above, I certify that 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) if promulgated, 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. A copy of the draft regulatory evaluation prepared for this action is contained in the Rules Docket. A copy of it may be obtained by contacting the Rules Docket at the location provided under the caption ADDRESSES.

List of Subjects in 14 CFR Part 39

• Air transportation
• Aircraft
• Aviation safety
• Safety

The Proposed Amendment

Accordingly, pursuant to the authority delegated to me by the Administrator, the Federal Aviation Administration proposes to amend 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.

§ 39.13

[Amended]

2. Section 39.13 is amended by adding the following new airworthiness directive:

McDonnell Douglas: Docket 2003-NM-43-AD.

Applicability: Model DC-10-10, DC-10-10F, DC-10-15, DC-10-30, DC-10-30F, DC-10-30F (KC-10A- and KDC-10), DC-10-40, DC-10-40F, MD-10-10F, and MD-10-30F airplanes as listed in Boeing Alert Service Bulletin DC10-57A149, dated January 7, 2003; and Model MD-11 and MD-11F airplanes, as listed in Boeing Alert Service Bulletin MD11-57A068, dated January 7, 2003; certificated in any category.

Compliance: Required as indicated, unless accomplished previously.

To prevent separation of the inboard flap outboard hinge from the wing structure and consequent reduced controllability of the airplane, accomplish the following:

Replacements Accomplished Per Previous Service Bulletins

(a) Replacements of steel bolts and nuts with Inconel bolts and nuts accomplished before the effective date of this AD per Boeing Service Bulletin DC10-57-116, Revision 01, dated November 25, 1996; Boeing Service Bulletin DC10-57-116, Revision 02, dated December 22, 1998; Boeing Service Bulletin DC10-57-116, Revision 03, dated May 12, 1999; and per Condition 1, Group 1 or 2, Option 1 of Boeing Alert Service Bulletin MD11-57A067, including Appendices A and B, dated July 10, 2002; are considered acceptable for compliance with the corresponding action specified in this AD.

General Visual Inspection, Model DC-10 and MD-10 Airplanes

(b) Within six months after the effective date of this AD, for all affected Model DC-10 and MD-10 airplanes, remove the encapsulating sealant from the nut side only of both assemblies and do a general visual inspection of the inboard flap, outboard hinge, forward attach bracket, lower attach bolt assembly nuts to detect cracking in the nuts, in accordance with the Accomplishment Instructions in Boeing Alert Service Bulletin DC10-57A149, dated January 7, 2003.

Note 1:

For the purposes of this AD, a general visual inspection is defined as: “A visual examination of an interior or exterior area, installation, or assembly to detect obvious damage, failure, or irregularity. This level of inspection is made from within touching distance unless otherwise specified. A mirror may be necessary to enhance visual access to all exposed surfaces in the inspection area. This level of inspection is made under normally available lighting conditions such as daylight, hangar lighting, flashlight, or droplight and may require removal or opening of access panels or doors. Stands, ladders, or platforms may be required to gain proximity to the area being checked.”

Replacement, Model DC-10 and MD-10 Airplanes

(c) Following the general visual inspection described in paragraph (b) of this AD, for all affected Model DC-10 and MD-10 airplanes, accomplish the applicable action(s) described in Table 1 of this AD at the specified times, per the Accomplishment Instructions in Boeing Alert Service Bulletin DC10-57A149, dated January 7, 2003. Although the Accomplishment Instructions specify to submit certain information and discrepant parts to the manufacturer, this AD does not include such a requirement.

Table 1.—Inspection and Replacement, Model DC-10 and MD-10 Airplanes

Condition	Actions to accomplish
(1) Cracks in either nut	(i) Option 1 (Preferred): Prior to further flight, replace both upper and lower attach bolt assemblies with new bolts and nuts made from Inconel material.
	(ii) Option 2: Prior to further flight, replace both lower attach bolt assemblies with new bolts and nuts made from Inconel material, and replace the preload-indicating (PLI) washers with new washers. Within 24 months after the effective date of this AD, replace both upper attach bolt assemblies with new bolts and nuts made from Inconel material, and replace the preload-indicating (PLI) washers with new washers.
(2) No cracks in nuts	Within 24 months after the effective date of this AD, replace both upper and lower attach bolt assemblies with bolts and nuts made from Inconel material, and replace the PLI washers with new washers, as applicable.

Replacement, Model MD-11 and -11F Airplanes

(d) Replace the inboard flap, outboard hinge, forward attach bracket, lower attach bolt assemblies of the affect Model MD-11 and MD-11F airplanes with new bolts and nuts made from Inconel material and replace the PLI washers with new PLI washers within the compliance time for the applicable condition described in Table 2 of this AD. Accomplish all replacements per the Accomplishment Instructions in Boeing Alert Service Bulletin MD11-57A068, dated January 7, 2003.

Table 2.—Condition and Compliance Time, Model MD-11 and -11F Airplanes

Condition	Compliance time
MD-11 and MD-11F airplanes that have not replaced steel bolts and nuts with new like parts or Inconel bolts per group 1 or 2, option 1 or 2 of Boeing Alert Service Bulletin MD11-57A067, including Appendices A and B, dated July 10, 2002	Within 18 months after the effective date of this AD.
MD-11 and MD-11F airplanes that have replaced steel bolts and nuts with new steel bolts and steel nuts per group 1 or 2, option 2, table 2, note 7 of Boeing Alert Service Bulletin MD11-57A067, including Appendices A and B, dated July 10, 2002	Within 36 months after the effective date of this AD.
MD-11 and MD-11F airplanes that have replaced steel bolts and nuts with new steel bolts and new Inconel nuts per Group 1 or 2, Option 2 of Boeing Alert Service Bulletin MD11-57A067, including Appendices A and B, dated July 10, 2002	Within 60 months after the date of this effective AD.

Alternative Methods of Compliance

(e) In accordance with 14 CFR 39.19, the Manager, Los Angeles Aircraft Certification Office (ACO), FAA, is authorized to approve alternative methods of compliance (AMOCs) for this AD.

Issued in Renton, Washington, on September 24, 2003.

Ali Bahrami,

Acting Manager, Transport Airplane Directorate, Aircraft Certification Service.