[Federal Register Volume 68, Number 246 (Tuesday, December 23, 2003)]
[Rules and Regulations]
[Pages 74173-74176]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 03-31273]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2003-NM-243-AD; Amendment 39-13397; AD 2003-26-01]
RIN 2120-AA64


Airworthiness Directives; Boeing Model 737-100, -200, -200C, -
300, -400, and -500 Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule; request for comments.

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SUMMARY: This amendment adopts a new airworthiness directive (AD) that 
is applicable to all Boeing Model 737-100, -200, -200C, -300, -400, and 
-500 series airplanes. This action requires a

[[Page 74174]]

one-time general visual inspection to identify the material of the 
rudder assembly, and corrective actions, if necessary. For airplanes 
with a graphite assembly, this action requires repetitive general 
visual inspections of the flange bolts of the rudder front spar for any 
loose bolts, and corrective actions, if necessary. This action is 
necessary to detect and correct loose bolts common to the flange of the 
rudder front spar and main thrust hinge and actuator assembly, as well 
as the auxiliary actuator support fitting, which could cause the rudder 
actuator to separate from the rudder during certain flight conditions, 
resulting in loss of rudder control and consequent loss of control of 
the airplane. This action is intended to address the identified unsafe 
condition.

DATES: Effective January 7, 2004.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of January 7, 2004.
    Comments for inclusion in the Rules Docket must be received on or 
before February 23, 2004.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 2003-NM-243-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: 
[email protected]. Comments sent via fax or the Internet must 
contain ``Docket No. 2003-NM-243-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 or 2000 or 
ASCII text.
    The service information referenced in this AD may be obtained from 
Boeing Commercial Airplane Group, PO 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: Nancy Marsh, Aerospace Engineer, 
Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office, 
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 
917-6440; fax (425) 917-6590.

SUPPLEMENTARY INFORMATION: The manufacturer, Boeing, has advised the 
FAA that it received two reports of loose bolts common to the flange of 
the rudder front spar and main thrust hinge and actuator assembly, as 
well as auxiliary actuator support fitting, on Boeing Model 737 series 
airplanes. In the first case, no additional damage was reported. In the 
second case, the holes common to the flange of the rudder front spar 
had become elongated and were repaired using oversized bolts.
    Boeing has notified us that it has received nine additional reports 
of loose flange bolts. In all of the reported cases (including the 
original two), the rudders had a graphite spar. The airplanes on which 
the loose flange bolts were found had between 7,246 and 45,312 total 
flight hours and between 7,846 and 35,362 total flight cycles. The 
cause of the loose flange bolts has not yet been determined.
    Loose bolts common to the flange of the rudder front spar and main 
thrust hinge and actuator assembly, as well as the auxiliary actuator 
support fitting, could cause the rudder actuator to separate from the 
rudder during certain flight conditions. This condition, if not 
detected and corrected, could result in loss of rudder control and 
consequent loss of control of the airplane.

Explanation of Relevant Service Information

    The FAA has reviewed and approved Boeing Alert Service Bulletin 
737-55A1087, dated October 2, 2003, which describes procedures for 
performing a one-time general visual inspection of the rudder assembly 
to determine if an aluminum/fiberglass rudder assembly, or, if a 
graphite rudder assembly, part number 65C27234-() or 65C25841-(), is 
installed; performing repetitive general visual inspections of the 
flange bolts (Stage 1); and corrective actions, if necessary. The 
corrective actions include retorqueing or replacing the flange bolts as 
necessary, and contacting Boeing for certain conditions.
    The alert service bulletin also describes additional Stage 2 and 
Stage 3 repetitive flange bolt inspections for certain airplanes.

Explanation of the Requirements of the Rule

    Since an unsafe condition has been identified that is likely to 
exist or develop on other airplanes of the same type design registered 
in the United States, this AD requires accomplishment of the actions 
specified in the alert service bulletin described previously, except as 
discussed below.

Interim Action

    This is considered to be interim action. We are continuing to 
investigate the cause of the loose flange bolts. Once the cause and 
final action have been identified, we may consider further rulemaking. 
We are, however, currently considering further rulemaking to supersede 
this AD to require the Stage 2 and Stage 3 repetitive inspections 
described in the alert service bulletin. Should we determine that those 
inspections are necessary, the planned compliance time would allow 
enough time to provide notice and opportunity for prior public comment.

Differences Between This AD and the Alert Service Bulletin

    Operators should note that Boeing Alert Service Bulletin 737-
55A1087, dated October 2, 2003, specifies inspections in addition to 
those required by this AD. As stated above, this AD does not require 
the Stage 2 and Stage 3 repetitive inspections because the planned 
compliance time for those inspections would allow enough time to 
provide notice and opportunity for prior public comment.
    Additionally, for any aluminum/fiberglass rudder assembly having an 
identification plate indicating a graphite assembly, or for any 
graphite rudder assembly having an identification plate indicating an 
aluminum assembly, the alert service bulletin specifies to contact 
Boeing for appropriate action. This AD requires operators to contact 
us, or a Boeing Company Designated Engineering Representative who has 
been authorized by us to make such findings.
    Although the Work Instructions of the alert service bulletin 
recommend that operators report inspection findings of any loose flange 
bolt to the manufacturer, this AD does not require operators to submit 
those inspection findings.

Explanation of Compliance Time for One-time Inspection

    Operators should note that the compliance time for accomplishment 
of the one-time inspection of the rudder assembly to identify the 
material of the rudder assembly and front spar and the initial Stage 1 
repetitive flange bolt inspection required by this AD is 120 days after 
the effective date of this AD. In developing an appropriate compliance 
time for this AD, we considered not only the manufacturer's 
recommendation, but also the degree of urgency associated with 
addressing the

[[Page 74175]]

subject unsafe condition, the significant impact on scheduling and cost 
for the large fleet of airplanes which must be inspected, and adequate 
time and availability of facilities for safe and accurate 
accomplishment of the inspection. In light of all of these factors, we 
find a 120-day compliance time for doing the flange bolt inspection to 
be warranted in that it represents an appropriate interval of time 
allowable for affected airplanes to continue to operate without 
compromising safety.

Determination of Rule's Effective Date

    Since a situation exists that requires the immediate adoption of 
this regulation, it is found that notice and opportunity for prior 
public comment hereon are impracticable, and that good cause exists for 
making this amendment effective in less than 30 days.

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.
    Submit comments using the following format:
    [sbull] 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.
    [sbull] For each issue, state what specific change to the AD is 
being requested.
    [sbull] 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 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 2003-NM-243-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

0
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

0
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]

0
2. Section 39.13 is amended by adding the following new airworthiness 
directive:

2003-26-01 Boeing: Amendment 39-13397. Docket 2003-NM-243-AD.

    Applicability: All Model 737-100, -200, -200C, -300, -400, and -
500 series airplanes, certificated in any category.
    Compliance: Required as indicated, unless accomplished 
previously.
    To detect and correct loose bolts common to the flange of the 
rudder front spar and main thrust hinge and actuator assembly, as 
well as the auxiliary actuator support fitting, which could cause 
the rudder actuator to separate from the rudder during certain 
flight conditions, resulting in loss of rudder control and 
consequent loss of control of the airplane; accomplish the 
following:

One-Time Inspection

    (a) For Groups 1, 2 and 3 airplanes, as listed in Boeing Alert 
Service Bulletin 737-55A1087, dated October 2, 2003: Within 120 days 
after the effective date of this AD, perform a one-time general 
visual inspection of the rudder assembly to determine if an 
aluminum/fiberglass rudder assembly (Group 1 airplanes), or, if a 
graphite rudder assembly, part number 65C27234-() or 65C25841-() 
(Group 2 and Group 3 airplanes) is installed; per the Work 
Instructions of Boeing Alert Service Bulletin 737-55A1087, dated 
October 2, 2003.

    Note 1: 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.''

    (b) If an aluminum/fiberglass assembly is found: No further 
action is required by paragraph (c) of this AD.

Stage 1--Repetitive Flange Bolt Inspections

    (c) If a graphite assembly is found: Within 120 days after the 
effective date of this AD, perform a general visual inspection of 
the flange bolts in the main thrust hinge and actuator assembly, as 
well as the auxiliary actuator support fitting to detect loose 
bolts, per ``Stage 1--Repeat Flange Bolt Inspection'' of the Work 
Instructions of Boeing Alert Service Bulletin 737-55A1087, dated 
October 2, 2003.
    (1) If no loose flange bolt is found: Repeat the inspection 
required by paragraph (c) of this AD at intervals not to exceed 
1,500 flight cycles or 2,000 flight hours, whichever occurs first.
    (2) If any loose flange bolt is found: Before further flight, do 
the applicable corrective actions by accomplishing all actions 
specified in paragraphs 4. and 5. of ``Stage 1--Repeat Flange Bolt 
Inspection'' of the Work Instructions of the alert service bulletin. 
Thereafter, repeat the inspection required by paragraph (c) of this 
AD at intervals not to exceed 1,500 flight cycles or 2,000 flight 
hours, whichever occurs first.

[[Page 74176]]

    (d) For any aluminum/fiberglass rudder assembly having an 
identification plate indicating a graphite assembly, or for any 
graphite rudder assembly having an identification plate indicating 
an aluminum assembly, and the alert service bulletin specifies to 
contact Boeing for appropriate action: Prior to further flight, 
contact the Manager, Seattle Aircraft Certification Office (ACO), 
FAA; or a Boeing Company Designated Engineering Representative who 
has been authorized by the Manager, Seattle ACO, to make such 
findings.

Parts Installation

    (e) As of the effective date of this AD, no person may install 
on any airplane a rudder assembly having part number 65C27234-() or 
65C25841-(), unless it has been inspected per paragraph (c) of this 
AD.

Information Submission

    (f) Although the service bulletin referenced in this AD 
specifies to submit inspection findings to the manufacturer, this AD 
does not include such a requirement.

Alternative Methods of Compliance

    (g) In accordance with 14 CFR 39.19, the Manager, Seattle 
Aircraft Certification Office (ACO), FAA, is authorized to approve 
alternative methods of compliance (AMOCs) for this AD.

Incorporation by Reference

    (h) Unless otherwise specified in this AD, the actions shall be 
done in accordance with Boeing Alert Service Bulletin 737-55A1087, 
dated October 2, 2003. 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, PO 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

    (i) This amendment becomes effective on January 7, 2004.

    Issued in Renton, Washington, on December 12, 2003.
Kevin M. Mullin,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 03-31273 Filed 12-22-03; 8:45 am]
BILLING CODE 4910-13-P