01-31558. Airworthiness Directives; Boeing Model 767-200 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 Boeing Model 767-200 series airplanes. This proposal would require repetitive inspections of the side panels of the nose wheel well for broken rivets and replacement of any broken rivets with bolts. This proposal would also require follow-on inspections of adjacent areas for cracks or broken rivets, whenever two or more adjacent broken rivets are found; repair of any cracks; and replacement of any broken rivets with bolts. Finally, this proposal provides for the optional replacement of all rivets in the affected area with bolts, which would terminate the repetitive inspections. This action is necessary to detect and correct broken rivets in the nose wheel well side panels and top panel, which could impair the function of the nose landing gear and cause fatigue cracks in the side panel and top panel webs of the nose wheel well, which could result in rapid cabin depressurization during flight. This action is intended to address the identified unsafe condition.

DATES:

Comments must be received by February 11, 2002.

ADDRESSES:

Submit comments in triplicate to the Federal Aviation Administration (FAA), Transport Airplane Directorate, ANM-114, Attention: Rules Docket Number 2000-NM-382-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. 2000-NM-382-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 Airplane Group, P.O. Box 3707, Seattle, Washington 98124-2207. This information may be examined at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington.

FOR FURTHER INFORMATION CONTACT:

John Craycraft, Aerospace Engineer, Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office, 1601 Lind Avenue, SW., Renton, Washington 98055-4056; 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 notice must submit a self-addressed, stamped postcard on which the following statement is made: “Comments to Docket Number 2000-NM-382-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 Number 2000-NM-382-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056.

Discussion

The FAA has received a report indicating that 155 broken rivets were found in the side and top panels of the nose wheel well on a Boeing Model 767-200 airplane. Analysis indicates that pressurization loads on the side panel and top panel webs results in high prying loads on these rivets. Broken rivets in the side and top panels of the nose wheel well, if not corrected, could impair the function of the nose landing gear and cause fatigue cracks in the side and top panel webs of the nose wheel well, which could result in rapid cabin depressurization during flight.

Explanation of Relevant Service Information

The FAA has reviewed and approved Boeing Service Bulletin 767-53A0090, Revision 1, dated September 14, 2000, which describes procedures for repetitive inspections of the nose wheel well side panels for broken rivets and replacement of any broken rivets with bolts. The service bulletin also describes procedures for follow-up inspections of adjacent areas for broken rivets and cracks, whenever two or more adjacent broken rivets are found; repair of any cracks; and replacement of any broken rivets with bolts. Finally, the service bulletin describes procedures for the optional replacement of all rivets in the affected area with bolts, which eliminates the need for repetitive inspections.

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 rule would require accomplishment of the actions specified in the service bulletin described previously, except as described below.

Differences Between Service Bulletin and Proposed Rule

Operators should note that the service bulletin specifies that if broken rivets are found during a secondary inspection, they must be repaired, and that repair data should be requested from the Boeing Company. However, this proposed rule would require the repair to be accomplished per a method approved by the FAA, or per data meeting the type certification basis of the airplane approved by a Boeing Company Designated Engineering Representative who has been authorized by the Manager, Seattle Aircraft Certification Office, to make such findings.

Cost Impact

There are approximately 62 airplanes of the affected design in the worldwide fleet. The FAA estimates that 46 airplanes of U.S. registry would be affected by this proposed AD, that it would take approximately 2 work hours per airplane to accomplish the proposed inspection, 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 $5,520, or $120 per airplane, per inspection cycle.

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 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:

Boeing: Docket 2000-NM-382-AD.

Applicability: Model 767 series airplanes, line numbers 1 through 62; certificated in any category.

Note 1:

This AD applies to each airplane identified in the preceding applicability provision, regardless of whether it has been modified, altered, or repaired in the area subject to the requirements of this AD. For airplanes that have been modified, altered, or repaired so that the performance of the requirements of this AD is affected, the owner/operator must request approval for an alternative method of compliance in accordance with paragraph (d) of this AD. The request should include an assessment of the effect of the modification, alteration, or repair on the unsafe condition addressed by this AD; and, if the unsafe condition has not been eliminated, the request should include specific proposed actions to address it.

Compliance: Required as indicated, unless accomplished previously.

To detect and correct broken rivets in the nose wheel well side panels and top panel, which could impair the function of the nose landing gear and cause fatigue cracks in the nose wheel well side panel and top panel webs, which could result in rapid cabin depressurization during flight, accomplish the following:

Initial and Repetitive Inspections

(a) Within 18 months or 3,000 flight cycles after the effective date of this AD, whichever occurs first: Perform a detailed visual inspection of the nose wheel well side panels for broken rivets, in accordance with Boeing Service Bulletin 767-53A0090, Revision 1, dated September 14, 2000.

Note 2:

For the purposes of this AD, a detailed visual inspection is defined as: “An intensive visual examination of a specific structural area, system, installation, or assembly to detect damage, failure, or irregularity. Available lighting is normally supplemented with a direct source of good lighting at intensity deemed appropriate by the inspector. Inspection aids such as mirror, magnifying lenses, etc., may be used. Surface cleaning and elaborate access procedures may be required.”

Note 3:

Inspections, replacement, and repairs performed prior to the effective date of this AD in accordance with Boeing Service Bulletin 767-53A0090, dated August 3, 2000, are considered acceptable for compliance with the applicable actions specified in this amendment.

(1) If no broken rivets are detected: No further action is required as part of the initial inspection. Repeat the inspection at intervals not to exceed 18 months or 3,000 flight cycles, whichever occurs first.

(2) If broken rivets are detected, but they do not include two or more adjacent rivets: Prior to further flight, replace the broken rivets with bolts in accordance with the service bulletin. Repeat the inspection at intervals not to exceed 18 months or 3,000 flight cycles, whichever occurs first.

(3) If two or more adjacent broken rivets are detected: Prior to further flight, perform a secondary inspection as specified in paragraph (c) of this AD.

Optional Terminating Action

(b) Replacement of all the rivets with bolts in accordance with Figure 5 of Boeing Service Bulletin 767-53A0090, Revision 1, dated September 14, 2000, terminates the repetitive inspection required by paragraph (a) of this AD.

Secondary Inspections

(c) If two or more adjacent broken rivets are found during any inspection required by paragraph (a) of this AD: Prior to further flight, perform a detailed visual inspection of the side panels and the top panel of the nose wheel well for cracks or broken rivets, in accordance with Boeing Service Bulletin 767-53A0090, Revision 1, dated September 14, 2000.

(1) If no cracks or additional broken rivets are found: Prior to further flight replace all of the rivets with bolts in accordance with Figure 5 of the service bulletin. This terminates the repetitive inspections required by paragraph (a) of this AD.

(2) If any cracks or additional broken rivets are found: Prior to further flight, repair the cracks and replace all of the rivets, per a method approved by the Manager, Seattle Aircraft Certification Office, or per data meeting the type certification basis of the airplane approved by a Boeing Company Designated Engineering Representative who has been authorized by the Manager, Seattle ACO, to make such findings. For a repair method to be approved by the Manager, Seattle ACO, as required by this paragraph, the Manager's approval letter must specifically reference this AD. This terminates the repetitive inspections required by paragraph (a) of this AD.

Alternative Methods of Compliance

(d) An alternative method of compliance or adjustment of the compliance time that provides an acceptable level of safety may be used if approved by the Manager, Seattle ACO. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, Seattle ACO.

Note 4:

Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Seattle ACO.

Special Flight Permits

(e) Special flight permits may be issued in accordance with sections 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 21.197 and 21.199) to operate the airplane to a location where the requirements of this AD can be accomplished.

Issued in Renton, Washington, on December 17, 2001.

Kalene C. Yanamura,

Acting Manager, Transport Airplane Directorate, Aircraft Certification Service.