[Federal Register Volume 66, Number 165 (Friday, August 24, 2001)]
[Proposed Rules]
[Pages 44553-44555]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 01-21224]


 ========================================================================
 Proposed Rules
                                                 Federal Register
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 This section of the FEDERAL REGISTER contains notices to the public of 
 the proposed issuance of rules and regulations. The purpose of these 
 notices is to give interested persons an opportunity to participate in 
 the rule making prior to the adoption of the final rules.
 
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 

  Federal Register / Vol. 66, No. 165 / Friday, August 24, 2001 / 
Proposed Rules  

[[Page 44553]]



DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2001-NM-198-AD]
RIN 2120-AA64


Airworthiness Directives; Boeing Model 767 Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: This document proposes the supersedure of an existing 
airworthiness directive (AD), applicable to certain Boeing Model 767 
series airplanes, that currently requires inspections and various 
follow-on actions to detect cracking and corrosion of the aft trunnion 
of the outer cylinder of the main landing gear (MLG). That action also 
requires termination of the inspections by repairing the outer cylinder 
and installing new aft trunnion bushings. This action would prohibit 
the use of a particular corrosion inhibiting compound during 
accomplishment of the terminating action. This action is necessary to 
prevent the collapse of the MLG due to stress corrosion cracking of the 
aft trunnion of the outer cylinder. This action is intended to address 
the identified unsafe condition.

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-198-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: 
[email protected]. Comments sent via fax or the Internet must 
contain ``Docket No. 2001-NM-198-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 (425) 
227-2782; fax (425) 227-1181.

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-198-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-198-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    On October 10, 1996, the FAA issued AD 96-21-06, amendment 39-9783 
(61 FR 55080, October 24, 1996), applicable to certain Boeing Model 767 
series airplanes, to require inspections and various follow-on actions 
to detect cracking and corrosion of the aft trunnion of the outer 
cylinder of the main landing gear (MLG). That action also requires 
termination of the inspections by repairing the outer cylinder and 
installing new aft trunnion bushings. That action was prompted by 
reports of failure of several MLG due to fracture of the aft trunnion 
outer cylinder. The requirements of that AD are intended to prevent the 
collapse of the MLG due to stress corrosion cracking of the aft 
trunnion of the outer cylinder.

Actions Since Issuance of Previous Rule

    Since the issuance of that AD, the airplane manufacturer has 
received reports indicating that a particular corrosion inhibiting 
compound has caused severe corrosion in the Model 767 MLG aft trunnion 
of the outer cylinder. The corrosion was found on MLGs that were 
previously reworked using Desoto 823E508 (Titanine JC5A) corrosion 
inhibiting compound 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 as the 
appropriate source of service information for accomplishing the 
terminating action).
    Over time, that particular corrosion inhibiting compound 
deteriorates and becomes hard and dry. If moisture

[[Page 44554]]

enters the outer cylinder aft trunnion and mixes with Titanine JC5A, a 
series of chemical reactions occurs and the reaction products can 
degrade the primer and cadmium plating. This may lead to corrosion in 
the aft trunnion where Titanine JC5A was used. Such corrosion, if not 
corrected, could result in the collapse of the MLG due to stress 
corrosion cracking of the aft trunnion of the outer cylinder.

Explanation of Relevant Service Information

    The FAA has reviewed and approved Boeing Service Bulletin 767-
32A0148, Revision 2, dated November 30, 2000. This revised service 
bulletin is essentially identical to the original version and Revision 
1 of the service bulletin. The only change effected by Revision 2 is to 
no longer allow the use of Desoto 823E508 (Titanine JC5A) as an option 
when incorporating that service bulletin. Revision 2 of the service 
bulletin adds Zip-Chem ZC-027L as an acceptable corrosion inhibiting 
compound. Zip-Chem ZC-027L and Mastinox 6856K are the only qualified 
BMS 3-27 products acceptable for use in incorporating that service 
bulletin. 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 supersede AD 96-21-06 to continue to require the 
actions specified by that AD. However, this proposed AD would prohibit 
the use of a particular corrosion inhibiting compound during 
accomplishment of the terminating action specified in AD 96-21-06. The 
actions would be required to be accomplished in accordance with the 
service bulletin described previously, as well as other service 
information specified in the existing AD.

Other Relevant Rulemaking

    The manufacturer has issued a related service bulletin, Boeing 
Alert Service Bulletin 767-32A0192, dated May 31, 2001, which gives 
instructions for inspections of the MLG to detect corrosion or 
cracking; corrective actions, if necessary; application of an alternate 
corrosion inhibiting compound; and terminating action for the 
inspections and corrosion inhibiting compound, for airplanes on which 
Desoto 823E508 (Titanine JC5A) has been used. The FAA is considering 
the issuance of a separate rulemaking action to further address the 
identified unsafe condition on airplanes on which Desoto 823E508 
(Titanine JC5A) was used.

Cost Impact

    There are approximately 605 airplanes of the affected design in the 
worldwide fleet. The FAA estimates that 200 airplanes of U.S. registry 
would be affected by this proposed AD.
    The actions that are currently required by AD 96-21-06 take 
approximately 252 work hours per airplane to accomplish, at an average 
labor rate of $60 per work hour. Required parts cost approximately 
$9,510 per airplane. Based on these figures, the cost impact of the 
currently required actions on U.S. operators is estimated to be 
$4,926,000, or $24,630 per airplane.
    The prohibition of a certain corrosion inhibiting compound proposed 
in this AD action would not change the cost impact on U.S. operators 
from that imposed by the superseded AD.
    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.


Sec. 39.13  [Amended]

    2. Section 39.13 is amended by removing amendment 39-9783 (61 FR 
55080, October 24, 1996), and by adding a new airworthiness directive 
(AD), to read as follows:

Boeing: Docket 2001-NM-198-AD. Supersedes AD 96-21-06, amendment 39-
9783.

    Applicability: Model 767 series airplanes having line numbers 
001 through 605 inclusive, on which the terminating action required 
by paragraph (e) of this AD has not been accomplished; certificated 
in any category.

    Note 1: This AD applies to each airplane identified in the 
preceding applicability provision, regardless of whether it has been 
otherwise 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 (i)(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 prevent collapse of the main landing gear (MLG) due to stress 
corrosion cracking of the aft trunnion of the outer cylinder, 
accomplish the following:

    Note 2: This AD is merely a restatement of the requirements of 
AD 96-21-06, amendment 39-9783, with one exception: Only Revision 2, 
dated November 30, 2000, of Boeing Service Bulletin 767-32A0148, 
which disallows the use of Desoto 823E508 (Titanine JC5A) corrosion 
inhibiting compound, may be used after the effective date of this 
new AD. As allowed by the phrase, ``unless accomplished 
previously,'' if

[[Page 44555]]

those requirements of AD 96-21-06 have already been accomplished 
prior to the effective date of this AD in accordance with prior 
versions of that service bulletin, this AD does not require that 
those actions be repeated. The FAA is, however, considering the 
issuance of a separate rulemaking action to further address the 
identified unsafe condition on airplanes on which Desoto 823E508 
(Titanine JC5A) was used.

Restatement of the Requirements of AD 96-21-06

Inspections and Various Follow-On Actions

    (a) Perform the inspections described in paragraph III, 
Accomplishment Instructions, of Boeing Alert Service Bulletin 767-
32A0151, dated November 30, 1995, or Revision 1, dated October 10, 
1996, to detect cracking and corrosion of the aft trunnion of the 
outer cylinder of the MLG at the time specified in paragraph (a)(1), 
(a)(2), or (a)(3) of this AD, as applicable. These inspections are 
to be accomplished in accordance with Figure 1 of the alert service 
bulletin. Repeat these inspections thereafter at the intervals 
specified in that alert service bulletin. To determine the category 
in which an airplane falls, the age of the outer cylinder of the MLG 
is to be calculated as of February 16, 1996 (the effective date of 
AD 96-03-02 R1, amendment 39-9526). For airplanes on which the age 
of the right MLG differs from the age of the left MLG, an operator 
may place the airplane into a category that is the higher 
(numerically) of the two categories to ease its administrative 
burden, and to simplify the recordkeeping requirements imposed by 
this AD. Once the category into which an airplane falls is 
determined, operators must obtain approval from the Manager, Seattle 
Aircraft Certification Office (ACO), FAA, to move that airplane into 
another category.

    Note 3: The broken (dash) lines used in Figure 1 of Boeing Alert 
Service Bulletin 767-32A0151, dated November 30, 1995, and Revision 
1, dated October 10, 1996, denote ``go to'' actions for findings of 
discrepancies detected during any of the inspections required by 
this AD.


    Note 4: Boeing Alert Service Bulletin 767-32A0151, dated 
November 30, 1995, and Revision 1, dated October 10, 1996, refer to 
Boeing Alert Service Bulletin 767-32A0148, dated December 21, 1995, 
and Revision 1, dated October 10, 1996, for procedures to repair the 
outer cylinder and replace the bushings in the outer cylinder of the 
MLG with new bushings.

    (1) For airplanes identified as Category 3 in paragraph I.C. of 
Boeing Alert Service Bulletin 767-32A0151, dated November 30, 1995, 
or Revision 1, dated October 10, 1996: Perform the initial 
inspections within 30 days after February 16, 1996 (the effective 
date of AD 96-03-02 R1, amendment 39-9526).
    (2) For airplanes identified as Category 2 in paragraph I.C. of 
Boeing Alert Service Bulletin 767-32A0151, dated November 30, 1995, 
or Revision 1, dated October 10, 1996: Perform the initial 
inspections within 90 days after February 16, 1996.
    (3) For airplanes identified as Category 1 in paragraph I.C. of 
Boeing Alert Service Bulletin 767-32A0151, dated November 30, 1995, 
or Revision 1, dated October 10, 1996: Perform the initial 
inspections prior to the accumulation of 2\1/2\ years since the MLG 
outer cylinder was new or last overhauled, or within 150 days after 
February 16, 1996, whichever occurs later.
    (b) If no cracking or corrosion is detected during the 
inspections required by paragraph (a) of this AD, accomplish the 
follow-on actions described in Boeing Alert Service Bulletin 767-
32A0151, November 30, 1995, or Revision 1, dated October 10, 1996, 
at the time specified in the alert service bulletin. These follow-on 
actions are to be accomplished in accordance with that alert service 
bulletin.
    (c) If any cracking is detected during the inspections required 
by paragraph (a) of this AD, prior to further flight, replace the 
outer cylinder with a new or serviceable outer cylinder in 
accordance with Boeing Alert Service Bulletin 767-32A0151, dated 
November 30, 1995, or Revision 1, dated October 10, 1996.
    (d) If any corrosion is detected during the inspections required 
by paragraph (a) of this AD, accomplish the follow-on actions at the 
time specified in the ``Corrosion Flowchart,'' in Figure 1 of Boeing 
Alert Service Bulletin 767-32A0151, dated November 30, 1995, or 
Revision 1, dated October 10, 1996. The follow-on actions are to be 
accomplished in accordance with that alert service bulletin.

Terminating Action

    (e) Unless previously accomplished in accordance with paragraph 
(e) of AD 96-21-06, at the time specified in either paragraph (e)(1) 
or (e)(2) of this AD, as applicable, repair the outer cylinder and 
replace the bushings in the aft trunnion and crossbolt of the MLG 
with new bushings, in accordance with Boeing Service Bulletin 767-
32A0148, Revision 2, dated November 30, 2000. Accomplishment of this 
repair and replacement constitutes terminating action for this AD, 
and for the requirements of AD 95-19-10, amendment 39-9372; and AD 
95-20-51, amendment 39-9398.

    Note 5: Boeing Service Bulletin 767-32A0148, Revision 2, dated 
November 30, 2000, refers to Boeing Component Maintenance Manual 
(CMM) 32-11-40 for certain procedures.

    (1) For airplanes identified as Category 3 in paragraph I.C. of 
Boeing Alert Service Bulletin 767-32A0151, dated November 30, 1995, 
or Revision 1, dated October 10, 1996: Accomplish the repair and 
replacement within 18 months after November 29, 1996 (the effective 
date of AD 96-21-06, amendment 39-9783).
    (2) For airplanes identified as either Category 1 or Category 2 
in paragraph I.C. of Boeing Alert Service Bulletin 767-32A0151, 
dated November 30, 1995, or Revision 1, dated October 10, 1996: 
Accomplish the repair and replacement at the time specified in 
either paragraph (e)(2)(i) or (e)(2)(ii) of this AD.
    (i) Prior to the accumulation of 5\1/2\ years since the MLG 
outer cylinders were new or last overhauled, or within 18 months 
after November 29, 1996, whichever occurs later; or
    (ii) Prior to the accumulation of 7 years since the MLG outer 
cylinders were new or last overhauled, provided that accomplishment 
of visual and non-destructive testing (NDT) inspections at the times 
specified in Figure 1 of the Accomplishment Instructions of Boeing 
Alert Service Bulletin 767-32A0151, dated November 30, 1995, or 
Revision 1, dated October 10, 1996, are repeated until the repair 
and replacement are accomplished.
    (f) Accomplishment of the inspection requirements of this AD (in 
accordance with Boeing Alert Service Bulletin 767-32A0151, dated 
November 30, 1995, or Revision 1, dated October 10, 1996) is 
considered acceptable for compliance with AD 95-19-10, amendment 39-
9372; and AD 95-20-51, amendment 39-9398.

New Requirement of This AD

    (g) As of the effective date of this AD, only Revision 2, dated 
November 30, 2000, of Boeing Service Bulletin 767-32A0148 shall be 
used to accomplish the actions required by paragraph (e) of this AD.

Use of Titanine JC5A Prohibited

    (h) As of the effective date of this AD, no person shall use the 
corrosion inhibiting compound Desoto 823E508 (Titanine JC5A) on any 
airplane.

Alternative Methods of Compliance

    (i)(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.

    Note 6: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Seattle ACO.

    (2) Alternative methods of compliance, approved in accordance 
with AD 96-03-02, amendment 39-9497; AD 96-03-02 R1, amendment 39-
9526; AD 95-19-10, amendment 39-9372; or AD 95-20-51, amendment 39-
9398; are approved as alternative methods of compliance with this AD 
except as required in paragraph (h) of this AD.

Special Flight Permits

    (j) 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 August 16, 2001.
Vi L. Lipski,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 01-21224 Filed 8-23-01; 8:45 am]
BILLING CODE 4910-13-U