AD 2001-09-51

[Federal Register Volume 66, Number 112 (Monday, June 11, 2001)]
[Rules and Regulations]
[Pages 31141-31143]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 01-13997]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2001-NM-126-AD; Amendment 39-12251; AD 2001-09-51]
RIN 2120-AA64


Airworthiness Directives; Boeing Model 737-600, -700, -700C, and 
-800 Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule; request for comments.

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SUMMARY: This document publishes in the Federal Register an amendment 
adopting airworthiness directive (AD) 2001-09-51 that was sent 
previously to all known U.S. owners and operators of Boeing Model 737-
600, -700, -700C, and -800 series airplanes by individual notices. This 
AD requires inspection of the small jam nut on the elevator tab control 
rods to detect inspection putty and to determine its condition; a 
torque check of the small and large jam nuts on the tab control rod, if 
necessary; and corrective actions, as applicable. For certain 
airplanes, this AD also requires a one-time inspection for torque of 
the small and large jam nuts on the tab control rods; and corrective 
actions, as applicable. This action is prompted by reports indicating 
that operators found problems with the elevator tab control rods during 
accomplishment of an existing AD. The actions specified by this AD are 
intended to prevent excessive freeplay in the tab control mechanism, 
which could result in elevator tab flutter and consequent loss of 
controllability of the airplane.

DATES: Effective June 18, 2001, to all persons except those persons to 
whom it was made immediately effective by emergency AD 2001-09-51, 
issued April 24, 2001, which contained the requirements of this 
amendment.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of June 18, 2001.
    Comments for inclusion in the Rules Docket must be received on or 
before August 10, 2001.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 2001-NM-126-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 (425) 227-1232. 
Comments may also be sent via the Internet using the following address: 
<a href="/cdn-cgi/l/email-protection#0e37236f606323676f7c6d6163636b607a4e686f6f20696178"><span class="__cf_email__" data-cfemail="c3faeea2adaeeeaaa2b1a0acaeaea6adb783a5a2a2eda4acb5">[email&#160;protected]</span></a>. Comments sent via fax or the Internet must 
contain ``Docket No. 2001-NM-126-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 applicable service information 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; or at the 
Office of the Federal Register, 800 North Capitol Street, NW., suite 
700, Washington, DC.

FOR FURTHER INFORMATION CONTACT: Kenneth J. Fairhurst, Aerospace 
Engineer, Systems and Equipment Branch, ANM-130S, FAA, Seattle Aircraft 
Certification Office, 1601 Lind Avenue, SW., Renton, Washington 98055-
4056; telephone (425) 227-1118; fax (425) 227-1181.

SUPPLEMENTARY INFORMATION: On April 24, 2001, the FAA issued emergency 
AD 2001-09-51, which is applicable to certain Boeing Model 737-600, -
700, -700C, and -800 series airplanes.
    That action was prompted by reports indicating that, during 
accomplishment of actions required by AD 2001-04-08, amendment 39-12127 
(66 FR 13229, March 5, 2001), operators found problems with the 
elevator tab control rods on certain Boeing Model 737-700 and -800 
series airplanes. One operator found jam nuts that had been installed 
improperly. Two other operators reported damage that was attributed to 
inadequately torqued jam nuts. The control rod jam nuts may not have 
been torqued properly when the control rod length was rigged at Boeing 
prior to delivery of the airplanes.
    Improperly torqued jam nuts on the elevator tab control rods could 
result in damage to the tab control rod. If both tab control rods are 
damaged, excessive freeplay in the tab control mechanism can occur, 
which could result in elevator tab flutter. This condition, if not 
corrected, could result in loss of controllability of the airplane.
    The elevator tab control rods on Model 737-600 and -700C series 
airplanes are identical to those on the affected Model 737-700 and -800 
series airplanes. Therefore, those Model 737-600 and -700C series 
airplanes may be

[[Page 31142]]

subject to the same unsafe condition revealed on Model 737-700 and -800 
series airplanes.

Explanation of Relevant Service Information

    The FAA has reviewed and approved Boeing Alert Service Bulletin 
737-27A1245, dated April 23, 2001, which describes procedures for 
inspecting the small jam nut on the elevator tab control rods to detect 
inspection putty and to determine its condition; a torque check of the 
small and large jam nuts on the tab control rod, if necessary; and 
corrective actions (including performing a detailed visual inspection 
of the threads on the rod end bearing for wear, measuring the diameter 
of the threads on the rod end bearing, replacing the rod end bearing 
and the threaded adjustment bushing, torquing the jam nuts, and 
applying inspection putty), as applicable.
    For any control rod jam nut on which the putty is found and is 
intact, the alert service bulletin also describes procedures for a one-
time inspection for torque of the small and large jam nuts on the tab 
control rods; and corrective actions (including performing a detailed 
visual inspection of the threads on the rod end bearing for wear, 
measuring the diameter of the threads on the rod end bearing, replacing 
the rod end bearing and the threaded adjustment bushing, torquing the 
jam nuts, and applying inspection putty), as applicable.

Explanation of Requirements of the Rule

    Since an unsafe condition has been identified that is likely to 
exist or develop on other airplanes of this same type design, this 
airworthiness directive is issued to require the actions specified in 
the alert service bulletin described previously. The actions are 
required to be accomplished in accordance with the alert service 
bulletin described previously.
    This AD also requires that operators report both positive and 
negative results of inspections to Boeing.
    Since it was found that immediate corrective action was required, 
notice and opportunity for prior public comment thereon were 
impracticable and contrary to the public interest, and good cause 
existed to make the AD effective immediately by individual notices 
issued on April 24, 2001, to all known U.S. owners and operators of 
Boeing Model 737-600, -700, -700C, and -800 series airplanes. These 
conditions still exist, and the AD is hereby published in the Federal 
Register as an amendment to section 39.13 of the Federal Aviation 
Regulations (14 CFR 39.13) to make it effective to all persons.

Clarification of Applicability

    For clarification, the FAA notes that, while the alert service 
bulletin does not specify that Model 737-700C series airplanes are 
subject to the actions in the alert service bulletin, the list of 
affected line numbers in the applicability of this AD includes the line 
numbers of certain Model 737-700C series airplanes.

Comments Invited

    Although this action is in the form of a final rule that involves 
requirements affecting flight safety and, thus, was not preceded by 
notice and an opportunity for public comment, comments are invited on 
this rule. Interested persons are invited to comment on this 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 under the caption ADDRESSES. All 
communications received on or before the closing date for comments will 
be considered, and this rule may be amended in light of the comments 
received. Factual information that supports the commenter's ideas and 
suggestions is extremely helpful in evaluating the effectiveness of the 
AD action and determining whether additional rulemaking action would be 
needed.
    Comments are specifically invited on the overall regulatory, 
economic, environmental, and energy aspects of the rule that might 
suggest a need to modify the 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 that 
summarizes each FAA-public contact concerned with the substance of this 
AD will be filed in the Rules Docket.
    Commenters wishing the FAA to acknowledge receipt of their comments 
submitted in response to this rule must submit a self-addressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket Number 2001-NM-126-AD.'' The postcard will be date stamped 
and returned to the commenter.

Regulatory Impact

    The regulations adopted herein will 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 final rule does not have federalism 
implications under Executive Order 13132.
    The FAA has determined that this regulation is an emergency 
regulation that must be issued immediately to correct an unsafe 
condition in aircraft, and that it is not a ``significant regulatory 
action'' under Executive Order 12866. It has been determined further 
that this action involves an emergency regulation under DOT Regulatory 
Policies and Procedures (44 FR 11034, February 26, 1979). If it is 
determined that this emergency regulation otherwise would be 
significant under DOT Regulatory Policies and Procedures, a final 
regulatory evaluation will be prepared and placed in the Rules Docket. 
A copy of it, if filed, may be obtained from the Rules Docket at the 
location provided under the caption ADDRESSES.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, Safety.

Adoption of the Amendment

    Accordingly, pursuant to the authority delegated to me by the 
Administrator, the Federal Aviation Administration amends 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 adding the following new 
airworthiness directive:

2001-09-51  Boeing: Amendment 39-12251. Docket 2001-NM-126-AD.

    Applicability: Model 737-600, -700, -700C, and -800 series 
airplanes, line numbers 1 through 788 inclusive, 790 through 814 
inclusive, 816, 819, 821, and 823, 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

[[Page 31143]]

been eliminated, the request should include specific proposed 
actions to address it.

    Compliance: Required as indicated, unless accomplished 
previously.
    To prevent excessive freeplay in the tab control mechanism, 
which could result in elevator tab flutter, and consequent loss of 
controllability of the airplane, accomplish the following:

Inspection and Corrective Actions

    (a) Within 10 days after the effective date of this AD, inspect 
the small jam nut on the elevator tab control rods to detect 
inspection putty and to determine its condition, per paragraph 
III.B. of the Accomplishment Instructions of Boeing Alert Service 
Bulletin 737-27A1245, dated April 23, 2001.
    (1) If inspection putty is found and it is intact, no further 
action is required by paragraph (a) of this AD.
    (2) If inspection putty is missing or detached, prior to further 
flight, perform a torque check of the small and large jam nuts on 
the tab control rod, in accordance with paragraph III.B. of the 
alert service bulletin. Prior to further flight, perform corrective 
actions (including performing a detailed visual inspection of the 
threads on the rod end bearing for wear, measuring the diameter of 
the threads on the rod end bearing, replacing the rod end bearing 
and the threaded adjustment bushing, torquing the jam nuts, and 
applying inspection putty), as applicable, per paragraph III.B. of 
the alert service bulletin. If the tab control rod is disassembled 
and if no wear is found during accomplishment of the detailed visual 
inspection specified in this paragraph, measuring the diameter of 
the threads on the rod end bearing may be deferred until 250 flight 
cycles or 30 days after the effective date of this AD, whichever 
occurs first.

    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.''

    (b) For any control rod jam nut on which the putty was found and 
was intact, as specified in paragraph (a)(1) of this AD: Within 250 
flight cycles or 30 days after the effective date of this AD, 
whichever occurs first, perform a one-time inspection for torque of 
the small and large jam nuts on the tab control rods, per paragraph 
III.C. of the Accomplishment Instructions of Boeing Alert Service 
Bulletin 737-27A1245, dated April 23, 2001. Prior to further flight, 
perform corrective actions (including performing a detailed visual 
inspection of the threads on the rod end bearing for wear, measuring 
the diameter of the threads on the rod end bearing, replacing the 
rod end bearing and the threaded adjustment bushing, torquing the 
jam nuts, and applying inspection putty), as applicable, per 
paragraph III.C. of the alert service bulletin.

Reporting Requirement

    (c) Within 15 days after accomplishing the inspections required 
by paragraphs (a) and (b) of this AD, submit a report of inspection 
findings, positive or negative, to Boeing per paragraph I.C. of the 
Planning Information of Boeing Alert Service Bulletin 737-27A1245, 
dated April 23, 2001. Information collection requirements contained 
in this regulation 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.

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

Incorporation by Reference

    (e) The actions shall be done in accordance with Boeing Alert 
Service Bulletin 737-27A1245, dated April 23, 2001. This 
incorporation by reference was approved by the Director of the 
Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 
51. Copies may be obtained from Boeing Commercial Airplane Group, 
P.O. Box 3707, Seattle, Washington 98124-2207. Copies may be 
inspected at the FAA, Transport Airplane Directorate, 1601 Lind 
Avenue, SW., Renton, Washington; or at the Office of the Federal 
Register, 800 North Capitol Street, NW., suite 700, Washington, DC.

Effective Date

    (f) This amendment becomes effective on June 18, 2001, to all 
persons except those persons to whom it was made immediately 
effective by emergency AD 2001-09-51, issued on April 24, 2001, 
which contained the requirements of this amendment.

    Issued in Renton, Washington, on May 25, 2001.
Vi L. Lipski,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 01-13997 Filed 6-8-01; 8:45 am]
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