Airworthiness Directives; McDonnell Douglas Model DC-8 Series 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-8 series airplanes. This proposal would require a one-time inspection to determine the manufacturer of the circuit breakers, and corrective action, if necessary. This proposal is prompted by reports of smoke and electrical odor in the flight compartment and cabin area as a result of failure of circuit breakers. The actions specified by the proposed AD are intended to prevent internal overheating and arcing of the circuit breakers and airplane wiring due to long-term use and breakdown of internal components of the circuit breakers, which could result in smoke and fire in the flight compartment and main cabin.

DATES:

Comments must be received by October 16, 2000.

ADDRESSES:

Submit comments in triplicate to the Federal Aviation Administration (FAA), Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 99-NM-272-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056. Comments may be inspected at this location between 9:00 a.m. and 3:00 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. 99-NM-272-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: Technical Publications Business Administration, Dept. C1-L51 (2-60). This information may be examined at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the FAA, Transport Airplane Directorate, Los Angeles Aircraft Certification Office, 3960 Paramount Boulevard, Lakewood, California.

FOR FURTHER INFORMATION CONTACT:

Elvin Wheeler, Aerospace Engineer, Systems and Equipment Branch, ANM-130L, FAA, Los Angeles Aircraft Certification Office, 3960 Paramount Boulevard, Lakewood, California 90712-4137; telephone (562) 627-5344; fax (562) 627-5210.

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 notice may be changed in light of the comments received.

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 notice must submit a self-addressed, stamped postcard on which the following statement is made: “Comments to Docket Number 99-NM-272-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. 99-NM-272-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056.

Supplementary Information

As part of its practice of re-examining all aspects of the service experience of a particular aircraft whenever an accident occurs, the FAA has become aware of instances of smoke and electrical odor in the flight compartment and cabin area of McDonnell Douglas Model DC-9 series airplanes. Investigation revealed that long-term use and breakdown of the internal components of the circuit breakers, manufactured by Wood Electric Corporation or Wood Electric Division of Potter Brumfield Corporation, contributed to internal overheating and arcing of the circuit breakers. This condition, if not corrected, could result in smoke and fire in the flight compartment and main cabin.

The subject circuit breakers on McDonnell Douglas Model DC-8 series airplanes are similar to those on the affected McDonnell Douglas Model DC-9 series airplanes. Therefore, both of these models may be subject to this same unsafe condition.

Other Related Rulemaking

The FAA is considering further rulemaking for certain McDonnell Douglas Model DC-9 series airplanes to address the identified unsafe condition.

The FAA, in conjunction with Boeing and operators of Model DC-8 series airplanes, is continuing to review all aspects of the service history of those airplanes to identify potential unsafe conditions and to take appropriate corrective actions. This proposed airworthiness directive (AD) is one of a series of actions identified during that process. The process is continuing and the FAA may consider additional rulemaking actions as further results of the review become available.

Explanation of Relevant Service Information

The FAA has reviewed and approved McDonnell Douglas Alert Service Bulletin DC8-24A075, Revision 01, dated September 21, 1999. The service bulletin describes procedures for a one-time inspection to determine the manufacturer of the circuit breakers, and replacement of any circuit breaker manufactured by Wood Electric Corporation or Wood Electric Division of Potter Brumfield Corporation with a new circuit breaker. Accomplishment of the actions specified in the 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, this proposed AD would require accomplishment of the actions specified in the service bulletin described previously, except as discussed below.

Differences Between Proposed AD and Service Bulletin

Operators should note that the proposed AD would require a one-time inspection to determine the manufacturer of the circuit breakers within 24 months after the effective date of this AD. The service bulletin recommends that the inspection be accomplished within 12 months from the issuance of the service bulletin. The proposed AD also would require replacement of the circuit breaker at the next scheduled maintenance visit, but not later than 24 months after the effective date of this AD. The service bulletin recommends that the replacement be accomplished prior to further flight. In developing an appropriate compliance time for these proposed actions, the FAA considered not only the degree of urgency associated with addressing the subject unsafe condition, but the availability of required parts. The FAA has determined that 24 months represents an appropriate interval of time allowable wherein an ample number of required parts will be available for inspection and replacement of the U.S. fleet within the proposed compliance period. The FAA also finds that such a compliance time will not adversely affect the safety of the affected airplanes.

Cost Impact

There are approximately 310 airplanes of the affected design in the worldwide fleet. The FAA estimates that 231 airplanes of U.S. registry would be affected by this proposed AD, it would take approximately 80 work hours per airplane to accomplish the proposed inspection of the circuit breakers (over 700 installed on each airplane), 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 $1,108,800, or $4,800 per airplane.

The cost impact figure discussed above is 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 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 substantial direct effects 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, in accordance with Executive Order 12612, it is determined that this proposal would not have sufficient federalism implications to warrant the preparation of a Federalism Assessment.

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.