01-21225. Airworthiness Directives; Boeing Model 767-200, -300, and -300F 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 all Boeing Model 767-200, -300, and -300F series airplanes. This proposal would require examination of maintenance records to determine if Titanine JC5A corrosion inhibiting compound (“C.I.C”) was ever used; inspection for cracks or corrosion and corrective action, if applicable; repetitive inspections and C.I.C. applications; and modification of the aft trunnion area of the outer cylinder, which terminates the need for the repetitive inspections and C.I.C. applications. This action is necessary to prevent severe corrosion in the main landing gear (MLG) outer cylinder at the aft trunnion, which could develop into stress corrosion cracking and consequent collapse of the MLG. This action is intended to address the identified unsafe condition. The FAA is also planning to issue additional rulemaking to exclude the use of Titanine JC5A for compliance with previously issued ADs.

DATES:

Comments must be received by September 24, 2001.

ADDRESSES:

Submit comments in triplicate to the Federal Aviation Administration (FAA), Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 2001-NM-189-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 [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. 2001-NM-189-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 action must submit a self-addressed, stamped postcard on which the following statement is made: “Comments to Docket Number 2001-NM-189-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-189-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056.

Discussion

The FAA has received reports indicating that an approved corrosion inhibiting compound (“C.I.C.”) has caused severe corrosion in the main landing gear (MLG) at the outer cylinder aft trunnion on Boeing Model 767 series airplanes. The corrosion was found on landing gear that were previously reworked using the C.I.C. Titanine JC5A (hereafter referred to as “JC5A”) during accomplishment of Boeing Alert Service Bulletin 767-32A0148, dated December 21, 1995, or Revision 1, dated October 10, 1996 (which were referenced in AD 96-21-06, amendment 39-9783 (61 FR 55080, October 24, 1996), as the appropriate source of service information for accomplishing the terminating action). During general maintenance; overhaul; accomplishment of Boeing Alert Service Bulletin 767-32A0148, dated December 21, 1995, or Revision 1, dated October 10, 1996; or when assembled new, JC5A was commonly used as a substitute for C.I.C. BMS 3-27 (Mastinox 6856K) on aft trunnion components.

Over time, the JC5A deteriorates and becomes hard and dry. If moisture enters the outer cylinder aft trunnion and mixes with JC5A, a series of chemical reactions occur and the reaction products degrade the primer and cadmium plating. This may lead to corrosion in the aft trunnion where the JC5A was used. There is more potential for corrosion in aft trunnions with an undercut on the inner diameter of the aft trunnion in the area of the bushing, which serves as a lubrication reservoir, which certain airplanes had as delivered. The presence of JC5A on the aft trunnion, if not corrected, could result in severe corrosion in the MLG outer cylinder at the aft trunnion, which could develop into stress corrosion cracking and consequent collapse of the MLG.

Explanation of Relevant Service Information

The FAA has reviewed and approved Boeing Alert Service Bulletin 767-32A0192, dated May 31, 2001. The service bulletin describes procedures for examination of airplane records to determine if JC5A C.I.C. was ever used; application of a different C.I.C.; inspections for cracks or corrosion of the cross bolt hole inner chamfer and cross bolt bushing holes and chamfers; and corrective and follow-on actions, if necessary. Corrective and follow-on actions include corrosion repair; repetitive inspections and C.I.C. applications; and modification of the aft trunnion area of the outer cylinder, which terminates the need for the repetitive inspections and C.I.C. applications. 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, the proposed AD would require accomplishment of the actions specified in the service bulletin described previously.

Cost Impact

There are approximately 806 airplanes of the affected design in the worldwide fleet. The FAA estimates that 489 airplanes of U.S. registry would be affected by this proposed AD. The approximate work hours required to accomplish the proposed actions are indicated in the table below. It is estimated that the average labor rate is $60 per work hour. Cost of required parts per airplane and the estimated cost impact of the proposed AD on U.S. operators is indicated in the table below.

Estimated Costs

Category	Labor costs (at $60 per hour)	Parts costs	Total cost per airplane	Total fleet cost (489 airplanes)
1	Inspection—Bushings Removed—25 hours/$1,500	[Reserved]	$1,500	$733,500
1	Inspection—Bushings Not Removed—20 hours/$1,200	[Reserved]	1,200	586,800
1	C.I.C. Application—5 hours/$300	[Reserved]	300	146,700
1	Terminating Action—218 hours/$13,080	$6,356	19,436	9,504,204
2	Inspection—Bushings Not Removed—20 hours/$1,200	[Reserved]	1,200	586,800
2	C.I.C. Application—5 hours/$300	[Reserved]	300	146,700
Category 1: Airplanes with an undercut in the aft trunnion bore.
Category 2: Airplanes without an undercut in the aft trunnion bore.

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:

Boeing: Docket 2001-NM-189-AD.

Applicability: All Model 767-200, -300, and -300F series airplanes, 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 (m) 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 prevent severe corrosion in the main landing gear (MLG) outer cylinder at the aft trunnion, which could develop into stress corrosion cracking and consequent collapse of the MLG, accomplish the following:

Records Examination

(a) Within 90 days after the effective date of this AD, examine airplane records to determine if Titanine JC5A (hereafter referred to as “JC5A”) corrosion inhibiting compound (“C.I.C.”) was used in the aft trunnion area of the MLG outer cylinder during general maintenance; overhaul; or incorporation of Boeing Alert Service Bulletin 767-32A0148, dated December 21, 1995, or Revision 1, dated October 10, 1996 (required by paragraph (e) of AD 96-21-06, amendment 39-9783), in accordance with Boeing Alert Service Bulletin 767-32A0192, dated May 31, 2001. If records do not show conclusively which compound was used, assume JC5A was used. Refer to Boeing Alert Service Bulletin 767-32A0192, dated May 31, 2001, for the line numbers of airplanes which were assembled new using JC5A.

Note 2:

Prior to January 31, 2001, if BMS 3-27 was ordered from Boeing, Boeing shipped JC5A as a substitute.

MLGs on Which JC5A Was Not Used

(b) Except as provided by paragraph (1) of this AD, if, according to the criteria of paragraph (a) of this AD, JC5A was never used, no further action is required by this AD.

C.I.C. Applications, Inspections, and Corrective Actions if Necessary

(c) For Category 1 MLG outer cylinders as identified in Boeing Alert Service Bulletin 767-32A0192, dated May 31, 2001: If, according to the criteria of paragraph (a) of this AD, JC5A may have been used, perform the actions specified in both paragraphs (d) and (e) of this AD, as applicable, in accordance with Boeing Alert Service Bulletin 767-32A0192, dated May 31, 2001.

(d) For MLGs and MLG outer cylinders identified in paragraphs (d)(1), (d)(2), and (d)(3) of this AD: Within 90 days after the effective date of this AD, perform the C.I.C. application on the MLG in accordance with “Part 3—C.I.C. Application” of the Accomplishment Instructions of Boeing Alert Service Bulletin 767-32A0192, dated May 31, 2001. Thereafter, repeat at intervals not to exceed 180 days until the terminating action required by paragraph (i) of this AD has been accomplished.

(1) MLG outer cylinders that are less than 3 years old since new.

(2) MLGs that have been overhauled less than 3 years ago.

(3) MLGs on which rework per Boeing Alert Service Bulletin 767-32A0148, dated December 21, 1995, or Revision 1, dated October 10, 1996, was accomplished less than 3 years ago.

(e) Before the MLG outer cylinder is 3 years old since new; since last overhaul; since rework per Boeing Alert Service Bulletin 767-32A0148, dated December 21, 1995, or Revision 1, dated October 10, 1996; or within 90 days after the effective date of this AD; whichever is later, perform a detailed visual inspection for cracks and corrosion of the cross bolt bushing holes and chamfers in accordance with “Part 1—Cross Bolt Hole Inspection—Bushings Removed” of the Accomplishment Instructions of Boeing Alert Service Bulletin 767-32A0192, dated May 31, 2001.

Note 3:

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.”

(1) If no crack or corrosion is found during the detailed visual inspection required by paragraph (e) of this AD, perform the actions in paragraphs (e)(1)(i), (e)(1)(ii), and (e)(1)(iii) of this AD, at the applicable times indicated.

(i) Before further flight, and thereafter at intervals not to exceed 180 days, perform the C.I.C. application on the landing gear in accordance with “Part 3—C.I.C. Application” of the Accomplishment Instructions of the service bulletin.

(ii) Within 18 months after performing the detailed visual inspection required by paragraph (e) of this AD, and thereafter at intervals not to exceed 18 months, perform the detailed visual inspection for cracks and corrosion of the cross bolt hole inner chamfer, in accordance with “Part 2—Cross Bolt Hole Inner Chamfer Inspection—Bushings Not Removed” of the Accomplishment Instructions of the service bulletin, until the terminating action required by paragraph (i) of this AD has been accomplished.

(iii) Before the MLG cylinder is 61/2years since new; since last overhaul; or since rework per Boeing Alert Service Bulletin 767-32A0148, dated December 21, 1995, or Revision 1, dated October 10, 1996; whichever is later, perform the terminating action described in paragraph (i) of this AD.

(2) If any corrosion is found on the cross bolt holes or outer chamfers during the detailed visual inspection required by paragraph (e) of this AD, before further flight, remove the corrosion per Figure 2 of the service bulletin.

(i) If all of the corrosion can be removed, before further flight, and thereafter at intervals not to exceed 180 days, perform the C.I.C. application on the MLG in accordance with “Part 3—C.I.C. Application” of the Accomplishment Instructions of the service bulletin, and perform the terminating action described in paragraph (i) of this AD, at the applicable time specified in paragraphs (e)(2)(i)(A) or (e)(2)(i)(B) of this AD.

(A) If the MLG outer cylinder is less than 5 years old since new; if the MLG was last overhauled less than 5 years ago; or, if rework per Boeing Alert Service Bulletin 767-32A0148, dated December 21, 1995, or Revision 1, dated October 10, 1996, was accomplished less than 5 years ago: Within 18 months after performing the detailed visual inspection required by paragraph (e) of this AD.

(B) If the MLG outer cylinder is 5 years old or more since new; if the MLG was last overhauled 5 years ago or more; or, if rework per Boeing Alert Service Bulletin 767-32A0148, dated December 21, 1995, or Revision 1, dated October 10, 1996, was accomplished 5 years ago or more: Before the MLG outer cylinder is 61/2 years old since new; since last overhaul; or since rework per Boeing Alert Service Bulletin 767-32A0148, dated December 21, 1995, or Revision 1, dated October 10, 1996; whichever is later.

(ii) If corrosion cannot be removed, before further flight, perform the terminating action described in paragraph (i) of this AD.

(3) If any crack is found anywhere during the detailed visual inspection required in paragraph (e) of this AD, or if corrosion in the inner cross bolt hole chamfers is found, before further flight, perform the terminating action described in paragraph (i) of this AD.

(f) For Category 2 MLG outer cylinders as identified in Boeing Alert Service Bulletin 767-32A0192, dated May 31, 2001: If, according to the criteria of paragraph (a) of this AD, JC5A may have been used, perform the actions specified in both paragraphs (g) and (h) of this AD, as applicable, in accordance with Boeing Alert Service Bulletin 767-32A0192, dated May 31, 2001.

(g) For MLGs and MLG outer cylinders identified in paragraphs (g)(1) and (g)(2) of this AD: Within 90 days after the effective date of this AD, perform the C.I.C. application on the MLG in accordance with “Part 3—C.I.C. Application” of the Accomplishment Instructions of Boeing Alert Service Bulletin 767-32A0192, dated May 31, 2001. Thereafter, repeat the application at intervals not to exceed 180 days until the terminating action required by paragraph (i) of this AD has been accomplished.

(1) MLG outer cylinders that are less than 3 years old since new.

(2) MLGs that have been overhauled less than 3 years ago.

(h) Before the MLG outer cylinder is 3 years old since new or since the last overhaul, or within 90 days of the effective date of this AD, whichever is later, perform a detailed visual inspection for cracks and corrosion of the cross bolt hole inner chamfer, in accordance with “Part 2—Crossbolt Hole Inner Chamfer Inspection—Bushings Not Removed” of the Accomplishment Instructions of Boeing Alert Service Bulletin 767-32A0192, dated May 31, 2001.

(1) If no crack or corrosion is found during the inspection required by paragraph (h) of this AD, before further flight, and thereafter at intervals not to exceed 180 days, perform the C.I.C. application on the MLG in accordance with “Part 3—C.I.C. Application” of the Accomplishment Instructions of the service bulletin, until the next MLG overhaul. After the next MLG overhaul has been completed, no further action is required by this AD.

(2) If any corrosion is found during the detailed visual inspection required by paragraph (h) of this AD, prior to further flight, remove the cross bolt bushings and perform the detailed visual inspection specified in paragraph (e) of this AD, and remove the corrosion per Figure 2 of the service bulletin.

(i) If all of the corrosion can be removed, perform the actions specified in paragraph (h)(2)(i)(A) and (h)(2)(i)(B) of this AD, at the applicable times indicated.

(A) Prior to further flight, and thereafter at intervals not to exceed 180 days, perform the C.I.C. application on the MLG in accordance with “Part 3—C.I.C. Application” of the Accomplishment Instructions of the service bulletin.

(B) Within 18 months after the corrosion removal required by paragraph (h)(2) of this AD, perform the terminating action described in paragraph (i) of this AD.

(ii) If all the corrosion cannot be removed, before further flight, perform the terminating action required by paragraph (i) of this AD.

(3) If any crack is found during the detailed visual inspection required by paragraph (h) of this AD, before further flight, perform the terminating action described in paragraph (i) of this AD.

Terminating Action

(i) Perform the terminating action (including removal of the existing bushings, repair of the aft trunnion area of the outer cylinder, and machining and installation of new bushings) in accordance with “Part 4—Terminating Action” of the Accomplishment Instructions of Boeing Alert Service Bulletin 767-32A0192, dated May 31, 2001. Completion of the terminating action terminates the requirements for the repetitive inspection and C.I.C. applications of this AD.

(j) Accomplishment of the actions specified in paragraph (i) of this AD is considered acceptable for compliance with the requirements of paragraph (e) of AD 96-21-06, amendment 39-9783.

Spares

(k) As of the effective date of this AD, no person shall install on any airplane an MLG outer cylinder unless it complies with either paragraph (b) or paragraph (i) of this AD, as applicable.

(l) As of the effective date of this AD, no person shall use on any airplane the corrosion inhibiting compound Titanine JC5A.

Alternative Methods of Compliance

(m) 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 Aircraft Certification Office (ACO), FAA. 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

(n) 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 August 16, 2001.

Vi L. Lipski,

Manager, Transport Airplane Directorate, Aircraft Certification Service.