Airworthiness Directives; McDonnell Douglas Model DC-10-10, DC-10-10F, DC-10-15, DC-10-30, DC-10-30F, DC-10-30F (KC10A and KDC-10), DC-10-40, DC-10-40F, MD-10-10F, MD-10-30F, 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 Model DC-10-10, DC-10-10F, DC-10-15, DC-10-30, DC-10-30F, DC-10-30F (KC10A and KDC-10), DC-10-40, DC-10-40F, MD-10-10F, MD-10-30F, MD-11, and MD-11F airplanes. This proposal would require a one-time inspection to determine the thickness of the walls of the rudder pedal arm assembly for the captain's and first officer's rudder pedals, and follow-on actions. This action is necessary to prevent failure of the rudder pedal arm assembly, which, under certain conditions, could result in reduced controllability of the airplane. This action is intended to address the identified unsafe condition.

DATES:

Comments must be received by October 21, 2002.

ADDRESSES:

Submit comments in triplicate to the Federal Aviation Administration (FAA), Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 2001-NM-207-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 (425) 227-1232. Comments may also be sent via the Internet using the following address: 9-anm-nprmcomment@faa.gov. Comments sent via fax or the Internet must contain “Docket No. 2001-NM-207-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 for Windows or ASCII text.

The service information referenced in the proposed rule may be obtained from 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:

Technical Information: Ron Atmur, Aerospace Engineer, Airframe Branch, ANM-120L, FAA, Los Angeles Aircraft Certification Office, 3960 Paramount Boulevard, Lakewood, California 90712-4137; telephone (562) 627-5224; fax (562) 627-5210.

Other Information: Judy Golder, Airworthiness Directive Technical Editor/Writer; telephone (425) 687-4241, fax (425) 227-1232. Questions or comments may also be sent via the Internet using the following address: judy.golder@faa.gov. Questions or comments sent via the Internet as attached electronic files must be formatted in Microsoft Word 97 for Windows or ASCII text.

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 2001-NM-207-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. 2001-NM-207-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056.

Discussion

The FAA has received a report indicating that the rudder pedal arm assembly for the captain and first officer was found broken on a McDonnell Douglas Model MD-11 airplane. Investigation revealed that the thickness of the walls of the rudder pedal arm was below the minimum design specification. The same rudder pedal arm assemblies are also installed on certain McDonnell Douglas Model DC-10-10, DC-10-10F, DC-10-15, DC-10-30, DC-10-30F, DC-10-30F (KC10A and KDC-10), DC-10-40, DC-10-40F, MD-10-10F, MD-10-30F, and MD-11F airplanes. Therefore, all of these models may be subject to the same unsafe condition.

Subsequent to the first report, we received several reports that, during inspections to determine the thickness of the walls of the rudder pedal assemblies, the clevis of the rudder pedal arm was found cracked or broken. The cracking of the clevis has been attributed to fatigue.

These conditions, if not corrected, could result in failure of the rudder pedal arm assembly. In the event of an engine failure while the airplane is in take-off configuration, such failure of the rudder pedal arm assembly could result in reduced controllability of the airplane.

Explanation of Relevant Service Information

We have reviewed and approved Boeing Alert Service Bulletin DC10-27A233, Revision 01, dated June 6, 2002 (for Model DC-10-10, DC-10-10F, DC-10-15, DC-10-30, DC-10-30F, DC-10-30F (KC10A and KDC-10), DC-10-40, DC-10-40F, MD-10-10F, MD-10-30F airplanes); and Boeing Alert Service Bulletin MD11-27A080, Revision 01, dated June 6, 2002 (for MD-11 and MD-11F airplanes). These service bulletins describe procedures for a one-time inspection to determine the thickness of the walls of the rudder pedal arm assembly for the captain's and first officer's rudder pedals, and these follow-on actions:

• If the wall thickness is within the design specifications or operational limits specified in the applicable service bulletin: Performing a dye penetrant inspection for cracking of the clevis of the rudder pedal arm assembly.
• If the wall thickness is within design specifications and no cracking is found (Condition 1): Performing repetitive dye penetrant inspections for cracking of the clevis of the rudder pedal assembly, or replacing the rudder pedal arm assembly with a new, improved assembly.
• If the wall thickness is within operational limits and no cracking is found (Condition 2): Changing the part number of the rudder pedal arm assembly to identify the assembly as a “temporary operation” part, and eventually replacing of the “temporary operation” rudder pedal arm assembly with a new, improved rudder pedal arm assembly.
• If the wall thickness is not within the limits in the service bulletin, or the clevis is cracked or broken (Condition 3 or 4): Replacing the rudder pedal assembly with a new, improved rudder pedal assembly.

Accomplishment of the actions specified in the applicable service bulletin 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 applicable service bulletin described previously, except as discussed below in the “Differences Between Service Bulletin and Proposed AD” section of this proposed AD.

Operators may note that the service bulletins described previously specify that, if the thickness of the walls of the rudder pedal arm assembly is within design specifications and no cracking of the clevis of the rudder pedal assembly is found (Condition 1), repetitive dye penetrant inspections for cracking of the clevis of the rudder pedal assembly may be accomplished in lieu of replacement of the rudder pedal arm assembly. We consider three criteria for situations in which repetitive inspections of a crack-prone area may be permitted to continue indefinitely, even though a positive fix to the problem exists: (1) The area is easily accessible, (2) the cracking is easily detectable, and (3) the consequences of the cracking are not likely to be catastrophic. In consideration of the cracking that may occur on the clevis of the rudder pedal assembly, we have determined that the circumstances warranting continual repetitive inspections meet these three criteria.

Differences Between Service Bulletin and Proposed AD

While the Revision Transmittal Sheet for Revision 01 of Boeing Alert Service Bulletin MD11-27A080 specifies an interval of 5,200 flight hours if repetitive inspections are necessary, this proposed AD would require such inspections, when necessary, to be done every 4,200 flight hours for MD-11 and MD-11F airplanes, as specified under paragraph 1.E. “Compliance” in that service bulletin.

Also, where paragraph 1.E. “Compliance” of Boeing Alert Service Bulletin MD11-27A080, Revision 01, specifies repetitive “close visual” inspections, this proposed AD would require repetitive dye penetrant inspections, as described in the Accomplishment Instructions of that service bulletin.

We have identified these discrepancies in the service bulletin to the airplane manufacturer. If it becomes necessary in the future to revise the service bulletin, the airplane manufacturer will be able to correct these discrepancies at that time.

Cost Impact

There are approximately 594 airplanes of the affected design in the worldwide fleet. We estimate that 366 airplanes of U.S. registry would be affected by this proposed AD, that it would take approximately 4 work hours per airplane to accomplish the proposed inspection to determine wall thickness, and that the average labor rate is $60 per work hour. Based on these figures, the cost impact of the proposed AD on U.S. operators is estimated to be $87,840, or $240 per airplane.

Should an operator be required to accomplish the follow-on inspection to detect cracking, the inspection would take approximately 1 work hour per airplane, at an average labor rate of $60 per work hour. Based on these figures, the cost impact of this inspection would be approximately $60 per airplane, per inspection cycle.

Should an operator be required to accomplish the replacement of a rudder pedal arm assembly, the replacement would take approximately 4 work hours per assembly, per airplane, at an average labor rate of $60 per work hour. Parts would cost approximately $2,943 per assembly. Based on these figures, the cost impact of this replacement would be approximately $3,148 per rudder pedal arm assembly, per airplane.

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.

For Model MD-11 and -11F airplanes within the period under the warranty agreement, we have been advised that the manufacturer has committed previously to its customers that it will bear the cost of replacement parts. We have also been advised that manufacturer warranty remedies may be available for labor costs associated with accomplishing the actions that would be required by this proposed AD. Therefore, the future economic cost impact of this AD may be less than the cost impact figure indicated above.

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.