03-5123. Airworthiness Directives; Boeing Model 767 Series Airplanes

AGENCY:

Federal Aviation Administration, DOT.

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

This document proposes the supersedure of an existing airworthiness directive (AD), applicable to certain Boeing Model 767 series airplanes, that currently requires a one-time inspection for missing bolts on the inboard and outboard support of the inboard main flap, and follow-on inspections and corrective actions, if necessary. For certain airplanes that are subject to the existing AD, this action would add requirements for a new one-time inspection for gaps, a new one-time torque check for loose bolts, corrective actions if necessary, and eventual replacement of existing titanium bolts with steel bolts. These actions are necessary to detect missing, loose, or cracked bolts on the supports of the inboard main flap and prevent loss of the inboard main flap, which could result in loss of control of the airplane. This action is intended to address the identified unsafe condition.

DATES:

Comments must be received by April 21, 2003.

ADDRESSES:

Submit comments in triplicate to the Federal Aviation Administration (FAA), Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 2002-NM-142-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. 2002-NM-142-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:

Suzanne Masterson, 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 action must submit a self-addressed, stamped postcard on which the following statement is made: “Comments to Docket Number 2002-NM-142-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. 2002-NM-142-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056.

Discussion

On October 24, 2002, the FAA issued AD 2002-22-07, amendment 39-12932 (67 FR 66043, October 30, 2002), applicable to certain Boeing Model 767 series airplanes, to require a one-time inspection for missing bolts on the inboard and outboard support of the inboard main flap, and follow-on inspections and corrective actions, if necessary. That action was prompted by an evaluation by the airplane manufacturer that revealed that the titanium bolts on the inboard main flap did not have an acceptable fatigue life or damage-tolerance rating, and a subsequent report indicating that an operator found one missing bolt and two loose bolts out of four bolts at the aft attachment locations on the outboard support of the inboard main flap. The requirements of that AD are intended to detect missing, loose, or cracked bolts on the supports of the inboard main flap and prevent loss of the inboard main flap, which could result in loss of control of the airplane.

Actions Since Issuance of Previous Rule

In the preamble to AD 2002-22-07, the FAA indicated that the actions required by that AD were considered “interim action” and that further rulemaking action was being considered to require the new inspection for gaps, the torque check for loose bolts, and the replacement of existing titanium bolts with steel bolts described in Boeing Alert Service Bulletin 767-27A0176, Revision 1, dated June 6, 2002. (The existing AD refers to that service bulletin as an appropriate source of service information for the required actions.) The FAA now has determined that further rulemaking action is indeed necessary, and this proposed AD follows from that determination.

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 supersede AD 2002-22-07 to continue to require a one-time inspection for missing bolts on the inboard and outboard support of the inboard main flap, and follow-on inspections and corrective actions, if necessary. These actions would continue to be required to be accomplished per Boeing Alert Service Bulletin 767-27A0176, Revision 1, except as specified under the heading “Differences Between This AD and Service Bulletin” in AD 2002-16-05, amendment 39-12844 (67 FR 52401, August 12, 2002). (AD 2002-22-07 superseded AD 2002-16-05.)

For certain airplanes, the proposed AD would add requirements for a new one-time inspection for gaps, a new one-time torque check for loose bolts, corrective actions if necessary, and eventual replacement of existing titanium bolts on the inboard and outboard supports of the inboard main flap with steel bolts. The actions would be required to be accomplished per Boeing Alert Service Bulletin 767-27A0176, Revision 1.

Cost Impact

There are approximately 821 airplanes of the affected design in the worldwide fleet. The FAA estimates that 374 airplanes of U.S. registry would be affected by this proposed AD.

The initial inspection that is currently required by AD 2002-16-05 takes approximately 6 work hours per airplane to accomplish, at an average labor rate of $60 per work hour. Based on these figures, the cost impact of the currently required inspection on U.S. operators is estimated to be $134,640, or $360 per airplane.

For an affected airplane, the new inspection for gaps that is proposed in this AD action would take approximately 1 work hour per airplane to accomplish, at an average labor rate of $60 per work hour. Based on these figures, the cost impact of this proposed inspection is $60 per airplane.

For an affected airplane, the new torque test that is proposed in this AD action would take approximately 6 work hours per airplane to accomplish, at an average labor rate of $60 per work hour. Based on these figures, the cost impact of this proposed torque test is $360 per airplane.

For an affected airplane, the replacement of bolts that is proposed in this AD action would take approximately 10 work hours per airplane to accomplish, at an average labor rate of $60 per work hour. Required parts would cost approximately $1,880 per airplane. Based on these figures, the cost impact of this proposed replacement is $2,480 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.

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 removing amendment 39-12932 (67 FR 66043, October 30, 2002), and by adding a new airworthiness directive (AD), to read as follows:

Boeing: Docket 2002-NM-142-AD. Supersedes AD 2002-22-07, Amendment 39-12932.

Applicability: Model 767 series airplanes, including Model 767-400ER series airplanes, line numbers 1 through 879 inclusive, 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 (h)(1) 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 missing, loose, or cracked bolts on the inboard and outboard support of the inboard main flap and prevent loss of the inboard main flap, which could result in loss of control of the airplane, accomplish the following:

Restatement of Requirements of AD 2002-22-07

Group 1 and 2 Airplanes: One-Time Inspection for Missing or Loose Bolts

(a) Within 90 days after August 27, 2002 (the effective date of AD 2002-16-05, amendment 39-12844), do a one-time general visual inspection to determine if any bolt is missing from the outboard support of the inboard main flap, per Part 2 or Part 8, as applicable, of the Accomplishment Instructions of Boeing Alert Service Bulletin 767-27A0176, Revision 1, dated June 6, 2002. Group 1 airplanes may comply with the replacement specified in paragraph (g) of this AD in lieu of the inspection in this paragraph, provided that the replacement per paragraph (g) of this AD is accomplished within the compliance time specified in this paragraph.

Note 2:

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.”

(1) If no bolt is missing, before further flight, do a general visual inspection for a gap between the nut and surrounding structure or between shim and joint (which would indicate a loose bolt), per Part 2 or Part 8, as applicable, of the Accomplishment Instructions of the service bulletin. If no bolt is missing and no gap is found, no further action is required by this paragraph.

(2) If any bolt is missing, before further flight, do paragraph (b) of this AD. In lieu of paragraph (b) of this AD, airplanes in Group 1 may comply with paragraph (g) of this AD.

Group 1 and 2 Airplanes: Missing Bolts or Gaps—Follow-On Actions

(b) For Group 1 or 2 airplanes as listed in Boeing Alert Service Bulletin 767-27A0176, Revision 1, dated June 6, 2002: If any bolt is missing or any gap is found during the inspections per paragraph (a) or (f) of this AD, before further flight, remove all of the bolts in the subject area and replace them with new or serviceable bolts, per Figure 6, 7, or 8 of the service bulletin, as applicable. For any attachment hole where the bolt was missing, install a new or serviceable bolt made from the same material as the other bolts, per the Accomplishment Instructions of the service bulletin.

(1) An existing bolt may be reinstalled if a fluorescent dye penetrant inspection for cracking is done per Part 5 of the Accomplishment Instructions of the service bulletin, and the bolt is found to be free of any crack.

(2) Do not intermix BACB30MR*K* bolts with BACB30LE*K* or BACB30US*K* bolts in the joints subject to this AD.

Model 767-400ER Series Airplanes: Initial Inspection and Corrective Actions

(c) For Model 767-400ER series airplanes: Within 90 days after August 27, 2002, do a one-time general visual inspection to determine if any bolt is missing from the inboard and outboard support of the inboard main flap, and do a detailed inspection for a gap between the nut and surrounding structure or between shim and joint (which would indicate a loose bolt), per Figure 2 of Boeing Alert Service Bulletin 767-27A0176, Revision 1, dated June 6, 2002.

(1) If no bolt is missing and no gap is found: No further action is required by this paragraph.

(2) If any bolt is missing or any gap is found: Do paragraphs (c)(2)(i) and (c)(2)(ii) of this AD.

(i) Before further flight, repair per a method approved by the Manager, Seattle Aircraft Certification Office (ACO), 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 ACO, to make such findings. For a repair method to be approved as required by this paragraph, the approval must specifically refer to this AD.

(ii) Within 10 days after the inspections: Submit a report of inspection findings to the Manager, Boeing Certificate Management Office, FAA, Transport Airplane Directorate, 2500 East Valley Road, Suite C2, Renton, Washington 98055; fax [phone]. The report must include the airplane's serial number, the total number of flight cycles and flight hours on the airplane, the number and specific location of discrepant bolts, and the nature of the discrepancy (i.e., missing bolt or gap found). Information collection requirements contained in this AD have been approved by the Office of Management and Budget (OMB) under the provisions of the Paperwork Reduction Act of 1980 (44 U.S.C. 3501 et seq.) and have been assigned OMB Control Number 2120-0056.

Previously Accomplished Inspections and Bolt Replacements

(d) Inspections and bolt replacements accomplished before the effective date of this AD per Boeing Alert Service Bulletin 767-27A0176, dated November 16, 2001, are acceptable for compliance with the corresponding actions required by this AD.

Group 1 and 2 Airplanes: One-Time Inspection for Missing or Loose Bolts

(e) Within 90 days after November 14, 2002 (the effective date of AD 2002-22-07, amendment 39-12932): Do the one-time general visual inspection required by paragraph (a) of this AD to determine if any bolt is missing from the inboard support of the inboard main flap, per Part 2 or Part 8, as applicable, of the Accomplishment Instructions of Boeing Alert Service Bulletin 767-27A0176, Revision 1, dated June 6, 2002. Group 1 airplanes may comply with the replacement specified in paragraph (g) of this AD in lieu of the inspection in this paragraph, provided that the replacement per paragraph (g) of this AD is accomplished within the compliance time specified in this paragraph.

New Requirements of This AD

Group 1 Airplanes: Follow-On Actions

(f) For Group 1 airplanes as listed in Boeing Alert Service Bulletin 767-27A0176, Revision 1, dated June 6, 2002: If no bolt is missing and no gap is found during the inspections required by paragraphs (a), (a)(1), and (e) of this AD, prior to the accumulation of 5,000 total flight cycles, or within 24 months after the effective date of this AD, whichever is later, perform a general visual inspection to find any gap between the nut and surrounding structure or between shim and joint (which would indicate a loose bolt), per Part 3 of the Accomplishment Instructions of the service bulletin.

(1) If no gap is found, before further flight, do a torque check per Part 4 of the Accomplishment Instructions of the service bulletin.

(i) If, during the torque check, the nut does not turn, remove the nut, clean the bolt and threads, and reinstall the nut per Part 4 and Figure 4 of the service bulletin. Do paragraph (g) of this AD at the time specified in that paragraph.

(ii) If the nut turns, do paragraph (b) of this AD. Then, do paragraph (g) of this AD at the time specified in that paragraph.

(2) If any gap is found, do paragraph (b) of this AD. Then, do paragraph (g) of this AD at the time specified in that paragraph.

Group 1 Airplanes: Replacement of Titanium Bolts

(g) For Group 1 airplanes as listed in Boeing Alert Service Bulletin 767-27A0176, Revision 1, dated June 6, 2002: Prior to the accumulation of 10,000 total flight cycles, or within 48 months after the effective date of this AD, whichever is later, replace all subject titanium bolts with new steel bolts per Part 6 of the Accomplishment Instructions of the service bulletin. This action is acceptable for compliance with paragraph (a), (e), and (f) of this AD and eliminates the need for the inspections required by those paragraphs. This action is acceptable for compliance with paragraph (b) of this AD, provided that the replacement of bolts per this paragraph is accomplished at the time specified in paragraph (b) of this AD. Do not intermix BACB30MR*K* bolts with BACB30LE*K* or BACB30US*K* bolts in the joints subject to this AD.

Alternative Methods of Compliance

(h)(1) 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.

(2) Alternative methods of compliance, approved previously in accordance with AD 2002-16-05, amendment 39-12844, and AD 2002-22-07, amendment 39-12932, are approved as alternative methods of compliance for the corresponding requirements of paragraphs (b) and (c)(2)(i) of this AD.

(3) Alternative methods of compliance, approved previously in accordance with paragraph (c) of AD 2002-16-05, amendment 39-12844, and AD 2002-22-07, amendment 39-12932, are approved as alternative methods of compliance for the requirements for paragraph (g) of this AD.

Note 3:

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

(i) Special flight permits may be issued in accordance with §§ 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 February 27, 2003.

Kalene C. Yanamura,

Acting Manager, Transport Airplane Directorate, Aircraft Certification Service.