[Federal Register Volume 67, Number 117 (Tuesday, June 18, 2002)]
[Proposed Rules]
[Pages 41355-41357]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 02-15244]


 ========================================================================
 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. 67, No. 117 / Tuesday, June 18, 2002 / 
Proposed Rules  

[[Page 41355]]



DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2001-NM-274-AD]
RIN 2120-AA64


Airworthiness Directives; Boeing Model 737-300, -400, and -500 
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 737-
300, -400, and -500 series airplanes, that currently requires 
replacement, with new parts, of the existing actuators or the rod ends 
on the existing actuators at wing leading edge slat positions 1, 2, 5, 
and 6. This new action would add a one-time inspection of all the rod 
ends on the actuators of the wing leading edge slats to determine if 
vibro-engraving was used to identify the parts, and corrective action, 
if necessary. This proposal is prompted by reports indicating that 
vibro-engraving was found on new rod ends during installation; such 
part markings create stress risers that reduce the fatigue life of the 
rod ends. The actions specified by the proposed AD are intended to 
prevent fatigue cracking, which could result in failure of the rod 
ends, uncommanded deployment of the wing leading edge slat, and 
consequent reduced controllability of the airplane. This action is 
intended to address the identified unsafe condition.

DATES: Comments must be received by August 2, 2002.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 2001-NM-274-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-274-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: Douglas Tsuji, Aerospace Engineer, 
Systems and Equipment Branch, ANM-130S, FAA, Transport Airplane 
Directorate, Seattle Aircraft Certification Office, 1601 Lind Avenue 
SW., Renton, Washington 98055-4056; telephone (425) 227-1506; 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-274-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-274-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    On January 18, 2000, the FAA issued AD 2000-02-03, amendment 39-
11521 (65 FR 3801, January 25, 2000), applicable to certain Boeing 
Model 737-300, -400 and -500 series airplanes, to require replacement, 
with new parts, of the existing actuators or the rod ends on the 
existing actuators at wing leading edge slat positions 1, 2, 5, and 6. 
That action was prompted by reports indicating that the rod ends on 
several leading edge slat actuators had fractured. The requirements of 
that AD are intended to prevent fatigue cracking of the rod ends of the 
leading edge slat actuators, which could result in uncommanded 
deployment of the wing leading edge slat and consequent reduced 
controllability of the airplane.

Actions Since Issuance of Previous Rule

    Since the issuance of AD 2000-02-03, the FAA has received a report 
indicating that vibro-engraving was found on a new rod end during 
accomplishment of Boeing Alert Service Bulletin 737-27A1211 (which was 
referenced in that AD as the appropriate source of service information 
for accomplishing the replacement of the existing actuators or the rod 
ends on the existing actuators with new parts). Subsequent to the first 
report, a second report was received that indicated vibro-engraving was 
found on

[[Page 41356]]

two sides of certain rod ends. Vibro-engraving creates stress risers in 
the rod ends that reduce the fatigue life of the part and can cause 
fatigue cracking. The manufacturer's rod end assembly drawings do not 
allow vibro-engraving as an acceptable part-marking method. Fatigue 
cracking of the rod ends on the actuators of the leading edge slats 
could result in failure of the rod ends, uncommanded deployment of the 
wing leading edge slat, and consequent reduced controllability of the 
airplane.

Explanation of Relevant Service Information

    The FAA has reviewed and approved Boeing Alert Service Bulletin 
737-27A1243, dated July 26, 2001. The service bulletin describes 
procedures for a visual inspection of all six rod ends on the actuators 
of the wing leading edge slats to determine if vibro-engraving was used 
to identify the parts, and corrective action if vibro-engraving is 
found on any rod end. The corrective action consists of rework or 
replacement of the affected rod end with a new rod end. Accomplishment 
of the actions specified in the service bulletin is intended to 
adequately address the identified unsafe condition.
    We also have reviewed and approved Boeing Alert Service Bulletin 
737-27A1211, Revision 2, dated December 21, 2000, including information 
notice (IN) 737-27A1211 IN 03, dated July 26, 2001. (The original 
version and Revision 1 of this service bulletin are referenced in the 
existing AD as service information for accomplishment of the specified 
actions). There are no significant changes to Revision 2; however, 
Information Notice 737-27A1211 IN 03 addresses vibro-engraving as an 
incorrect method of identification of the rod ends and instructs 
operators to return vibro-engraved parts to the vendor, or to do the 
procedures specified in Boeing Alert Service Bulletin 737-27A1243 
(described above).

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 2000-02-03 to continue to require 
replacement, with new parts, of the existing actuators or the rod ends 
on the existing actuators at wing leading edge slat positions 1, 2, 5, 
and 6. This new action would add a one-time inspection of the rod ends 
on the actuators of the wing leading edge slats to determine if vibro-
engraving was used to identify the parts, and corrective action, if 
necessary. The actions would be required to be accomplished in 
accordance with the service bulletins described previously, except as 
discussed below.

Difference Between This Proposed AD and the Service Bulletin

    The service bulletin recommends a visual inspection of all six rod 
ends on the actuators of the wing leading edge slats ``at the earliest 
convenient maintenance opportunity'' to determine if vibro-engraving 
was used to identify the rod ends, then reworking or replacing the 
parts that have vibro-engraving within 42 months after incorporation of 
Boeing Service Bulletin 737-27A1211 (described above). However, the FAA 
has determined that ``at the earliest convenient maintenance 
opportunity'' may not ensure that the identified unsafe condition is 
addressed in a timely manner. In developing an appropriate compliance 
time for this proposed AD, we considered not only the manufacturer's 
recommendation, but the degree of urgency associated with addressing 
the subject unsafe condition, the average utilization of the affected 
fleet, and the time necessary to accomplish the proposed AD. In light 
of all of these factors, we find a compliance time of 12,000 flight 
cycles or 42 months after doing the replacement required by AD 2000-02-
03, whichever is first; or 12,000 flight cycles or 42 months after the 
effective date of the AD, whichever is first; as applicable; to be 
warranted, in that it represents an appropriate interval of time 
allowable for affected airplanes to continue to operate without 
compromising safety.

Cost Impact

    There are approximately 1,963 airplanes of the affected design in 
the worldwide fleet. The FAA estimates that 799 airplanes of U.S. 
registry would be affected by this proposed AD.
    Replacement of the leading edge slat actuator with an actuator that 
has a new rod end is one option for compliance with the actions 
currently required by AD 2000-02-03. Replacement of the actuators on 
slat positions 1, 2, 5, and 6 takes approximately 3 work hours per 
airplane to accomplish, at an average labor rate of $60 per work hour. 
Required parts cost approximately $32,252 per airplane. Based on these 
figures, the cost impact of the installation of actuators with new rod 
ends, as provided as one option by this AD, is estimated to be $32,432 
per airplane.
    In lieu of installation of an actuator with a new rod end, AD 2000-
02-03 provides an option for replacement of the rod ends on the 
existing actuators. This action takes approximately 4 work hours per 
airplane to accomplish, at an average labor rate of $60 per work hour. 
Required parts cost between approximately $5,928 and $21,544 per 
airplane. Based on these figures, the cost impact of the replacement of 
the rod ends, as provided as a second option by this AD, is estimated 
to be between $6,168 and $21,784 per airplane.
    The new inspection that is proposed in this AD action would take 
approximately 2 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 inspection proposed by this AD on U.S. operators is 
estimated to be $95,880, or $120 per airplane.
    The cost impact figures discussed above are based on assumptions 
that no operator has yet accomplished any of the current or 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.
    Should an operator be required to accomplish the replacement of the 
rod end, it would take approximately 1 work hour per rod end to 
accomplish the replacement, at an average labor rate of $60 per work 
hour. Required parts would cost between $2,917 and $5,527 per rod end. 
Based on these figures, the cost impact of any replacement action is 
estimated to be between $2,977 and $5,587 per rod end.
    Should an operator be required to accomplish the rework of the rod 
end, it would take approximately 2 work hours per rod end to accomplish 
the rework, at an average labor rate of $60 per hour. Based on these 
figures, the cost impact of the rework is estimated to be $120 per rod 
end.

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.

[[Page 41357]]

    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 39-11521 (65 FR 
3801, January 25, 2000), and by adding a new airworthiness directive 
(AD), to read as follows:

Boeing: Docket 2001-NM-274-AD. Supersedes AD 2000-02-03, Amendment 
39-11521.

    Applicability: Model 737-300, -400, and -500 series airplanes; 
line numbers 1001 through 3132 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 (e)(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 fatigue cracking of the rod ends of the actuators of 
the leading edge slats, which could result in failure of the rod 
ends, uncommanded deployment of the wing leading edge slat, and 
consequent reduced controllability of the airplane, accomplish the 
following:

Restatement of Requirements of AD 2000-02-03

Replacement

    (a) Within 24 months after February 29, 2000 (the effective date 
of AD 2000-02-03, amendment 39-11521): Replace the leading edge slat 
actuator with an actuator that has a new rod end, or replace the rod 
end on the existing slat actuator with a new rod end, at slat 
positions 1, 2, 5, and 6; in accordance with the Accomplishment 
Instructions in Boeing Alert Service Bulletin 737-27A1211, dated 
November 19, 1998; Revision 1, dated December 9, 1999; or Revision 
2, dated December 21, 2000, including information notice (IN) 737-
27A1211 IN 03, dated July 26, 2001.

Spares

    (b) As of February 29, 2000, no person shall install any part 
having a part number identified in the ``Existing Part Number'' 
column of Section 2.E. of Boeing Alert Service Bulletin 737-27A1211, 
dated November 19, 1998, on any airplane.

New Requirements of This AD

One-Time Inspection/Corrective Action

    (c) Do a one-time general visual inspection of all six rod ends 
on the actuators of the wing leading edge slats to determine if 
vibro-engraving was used to identify the rod ends, at the time 
specified in paragraph (c)(1) or (c)(2) of this AD, as applicable, 
per the Work Instructions of Boeing Alert Service Bulletin 737-
27A1243, dated July 26, 2001. If vibro-engraving is found, rework or 
replace the affected rod end with a new rod end at the time 
specified in paragraph (c)(1) or (c)(2) of this AD, as applicable, 
per the service bulletin. If no vibro-engraving is found, no further 
action is required by 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) For airplanes on which the rod ends were replaced as 
required by paragraph (a) of this AD: Within 12,000 flight cycles or 
42 months after doing the replacement per paragraph (a) of this AD, 
whichever is first.
    (2) For all other airplanes: Within 12,000 flight cycles or 42 
months after the effective date of this AD, whichever is first.

Spares

    (d) After the effective date of this AD, no person shall install 
on any airplane a rod end having vibro-engraving, or other part 
markings that penetrate the surface, unless that part has been 
reworked as required by this AD.

Alternative Methods of Compliance

    (e)(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 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.
    (2) Alternative methods of compliance, approved previously in 
accordance with AD 2000-02-03, amendment 39-11521, are approved as 
alternative methods of compliance with paragraph (a) 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

    (f) 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 June 7, 2002.
Ali Bahrami,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 02-15244 Filed 6-17-02; 8:45 am]
BILLING CODE 4910-13-P