AD 2002-22-05
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Boeing | 737-100 | Airworthiness Directives; Boeing Model 737-100, -200, -200C, -300, -400, and -500 Series Airplanes |
Unsafe Condition
Cracks, fractures, or corrosion of the carriage spindle of the left and right outboard mid-flaps could lead to severe flap asymmetry, potentially resulting in reduced control or loss of controllability of the airplane.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Inspect each carriage spindle of the left and right outboard mid-flaps for cracks, fractures, or corrosion. Take corrective action if necessary. Optionally, overhaul or replace the carriage spindles to extend the inspection interval.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Within 50 flight hours after the effective date of the AD.
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
Boeing Model 737-100, -200, -200C, -300, -400, and -500 series airplanes.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
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 repetitive inspections to find cracks, fractures, or corrosion of each carriage spindle of the left and right outboard mid-flaps; and corrective action, if necessary. This action also provides for an optional action of overhaul or replacement of the carriage spindles, which would extend the repetitive inspection interval. This action is necessary to prevent severe flap asymmetry due to fractures of the carriage spindles on an outboard mid- flap, which could result in reduced control or loss of controllability of the airplane. This action is intended to address the identified unsafe condition.
Document Text
Show stored source text (verify against official source)
[Federal Register Volume 67, Number 211 (Thursday, October 31, 2002)]
[Rules and Regulations]
[Pages 66316-66318]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 02-27315]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 2002-NM-214-AD; Amendment 39-12929; AD 2002-22-05]
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 repetitive inspections to
find cracks, fractures, or corrosion of each carriage spindle of the
left and right outboard mid-flaps; and corrective action, if necessary.
This action also provides for an optional action of overhaul or
replacement of the carriage spindles, which would extend the repetitive
inspection interval. This action is necessary to prevent severe flap
asymmetry due to fractures of the carriage spindles on an outboard mid-
flap, which could result in reduced control or loss of controllability
of the airplane. This action is intended to address the identified
unsafe condition.
DATES: Effective November 15, 2002.
The incorporation by reference of certain publications listed in
the regulations is approved by the Director of the Federal Register as
of November 15, 2002.
Comments for inclusion in the Rules Docket must be received on or
before December 30, 2002.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), Transport Airplane Directorate, ANM-114,
Attention: Rules Docket No. 2002-NM-214-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#a89185c9c6c585c1c9dacbc7c5c5cdc6dce8cec9c986cfc7de"><span class="__cf_email__" data-cfemail="ebd2c68a8586c6828a99888486868e859fab8d8a8ac58c849d">[email protected]</span></a>. Comments sent via fax or the Internet must
contain ``Docket No. 2002-NM-214-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 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: Technical Information: Sue Lucier,
Aerospace Engineer, Airframe Branch, ANM-120S, FAA, Seattle Aircraft
Certification Office, 1601 Lind Avenue, SW., Renton, Washington 98055-
4056; telephone (425) 227-2186; fax (425) 227-1181.
Other Information: Sandi Carli, Airworthiness Directive Technical
Editor/Writer; telephone (425) 687-4243, fax (425) 227-1232. Questions
or comments may also be sent via the Internet using the following
address: <a href="/cdn-cgi/l/email-protection#57243639333e793436253b3e1731363679303821"><span class="__cf_email__" data-cfemail="a0d3c1cec4c98ec3c1d2ccc9e0c6c1c18ec7cfd6">[email protected]</span></a>. Questions or comments sent via the
Internet as attached electronic files must be formatted in Microsoft
Word 97 for Windows or ASCII text.
SUPPLEMENTARY INFORMATION: The FAA has received reports indicating
fractures of the carriage spindles of the outboard mid-flaps on certain
Boeing Model 737 series airplanes. The fractures resulted from stress-
corrosion cracking. The most critical section for a fracture is at the
forward end of the spindle; two of the thirteen reported fractures
occurred in this area on airplanes that had accumulated between 4,198
and 43,919 total flight cycles. In a recent incident, dual failure of
the carriage spindles occurred and one of the spindles failed at a
location critical for continued flap functionality. If one carriage
spindle fractures on a flap, it will affect control of flight of the
airplane. If both the inboard and outboard spindles fracture in the
critical section on an outboard
[[Page 66317]]
flap, it could result in loss of controllability of the airplane.
Related Rulemaking
This AD is related to AD 90-17-19, amendment 39-6705 (55 FR 33280,
August 15, 1990). That AD is applicable to all Boeing Model 747 series
airplanes, except Model 747SP, and requires periodic inspections of
both inboard and outboard trailing edge flap carriage spindles for
cracks and corrosion, and overhaul or replacement, if necessary. That
AD also requires periodic inspections to detect cracks or corrosion of
all exposed surfaces of the carriage spindles, including inner bore,
and aft links; and overhaul or replacement, if necessary. That AD also
shortens certain compliance intervals to ensure continued
airworthiness.
This AD requires similar actions for all Boeing Model 737-100, -
200, -200C, -300, -400, and -500 series airplanes, because the carriage
spindles on the outboard mid-flaps are very similar to the carriage
spindles on Model 747 series airplanes.
Explanation of Relevant Service Information
We have reviewed and approved Boeing Alert Service Bulletin 737-
57A1277, dated July 25, 2002, which describes procedures for repetitive
nondestructive test (NDT) inspections to find cracks, fractures, or
corrosion of each carriage spindle of the left and right outboard mid-
flaps; and corrective action, if necessary. The corrective action
includes overhaul or replacement of the carriage spindle if any cracks,
fractures, or corrosion are found. The service bulletin also recommends
that a report be sent to the manufacturer if a crack or fracture of any
carriage spindle is found. Accomplishment of the actions specified in
the service bulletin is intended to adequately address the identified
unsafe condition
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, the
actions in this AD are required to be accomplished in accordance with
the service bulletin described previously, except as discussed below.
Differences Between AD and Service Information
The service bulletin explicitly specifies doing a NDT inspection
for cracks or fractures of each carriage spindle, and indicates that
operators should look for cracking or corrosion of the exposed portion
of the spindle. We infer that this description is that of a general
visual inspection; therefore, this AD adds a general visual inspection
for cracks, fractures, or corrosion of the spindle. We have added a
note to this AD to define such an inspection.
Although the service bulletin recommends that operators report
inspection findings of any crack or fracture in the carriage spindle to
the manufacturer, this AD does not contain such a reporting
requirement.
Interim Action
This is considered to be interim action. We are currently
considering mandating overhaul or replacement of the carriage spindles,
which will extend the interval for the repetitive inspections required
by this AD action. This action is similar to that required by AD 90-17-
19, discussed above. However, the planned compliance time for the
overhaul or replacement action is sufficiently long so that notice and
opportunity for prior public comment will be practicable.
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 2002-NM-214-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
[[Page 66318]]
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:
2002-22-05 Boeing: Amendment 39-12929. Docket 2002-NM-214-AD.
Applicability: All Model 737-100, -200, -200C, -300, -400, and -
500 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 (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 been
eliminated, the request should include specific proposed actions to
address it.
Compliance: Required as indicated, unless accomplished
previously.
To prevent severe flap asymmetry due to fractures of the
carriage spindles on an outboard mid-flap, which could result in
reduced control or loss of controllability of the airplane,
accomplish the following:
Repetitive Inspections
(a) Do general visual and nondestructive test (NDT) inspections
of each carriage spindle (two on each flap) of the left and right
outboard mid-flaps to find cracks, fractures, or corrosion at the
later of the times specified in paragraphs (a)(1) and (a)(2) of this
AD, as applicable, per the Work Instructions of Boeing Alert Service
Bulletin 737-57A1277, dated July 25, 2002. Repeat the inspection at
least every 180 days until paragraph (c) of this AD is done.
(1) Before the accumulation of 12,000 total flight cycles or 8
years in-service on new or overhauled carriage spindles, whichever
is first.
(2) Within 90 days after the effective date of this AD.
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.''
Corrective Action
(b) If any crack, fracture, or corrosion is found during any
inspection required by paragraph (a) of this AD: Before further
flight, do the applicable actions for that spindle as specified in
paragraph (b)(1) or (b)(2) of this AD, per the Work Instructions of
Boeing Alert Service Bulletin 737-57A1277, dated July 25, 2002. Then
repeat the inspections required by paragraph (a) of this AD every
12,000 flight cycles or 8 years, whichever is first; on the
overhauled or replaced spindle only.
(1) If any corrosion is found in the carriage spindle, overhaul
the spindle.
(2) If any crack or fracture is found in the carriage spindle,
replace with a new or overhauled carriage spindle.
Note 3: Although the service bulletin recommends that operators
report inspection findings of any crack or fracture in the carriage
spindle to the manufacturer, this AD does not contain such a
reporting requirement.
Optional Overhaul or Replacement
(c) Overhaul or replacement, as applicable, of all four carriage
spindles, per the Work Instructions of Boeing Alert Service Bulletin
737-57A1277, dated July 25, 2002, extends the repetitive inspection
interval specified in paragraph (a) of this AD to every 12,000
flight cycles or 8 years, whichever is first.
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 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
(e) 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.
Incorporation by Reference
(f) The actions shall be done in accordance with Boeing Alert
Service Bulletin 737-57A1277, dated July 25, 2002. 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
(g) This amendment becomes effective on November 15, 2002.
Issued in Renton, Washington, on October 22, 2002.
Vi L. Lipski,
Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 02-27315 Filed 10-30-02; 8:45 am]
BILLING CODE 4910-13-P
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