[Federal Register: January 30, 2004 (Volume 69, Number 20)]
[Rules and Regulations]               
[Page 4452-4454]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr30ja04-4]                         

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2001-NM-88-AD; Amendment 39-13443; AD 2004-02-08]
RIN 2120-AA64

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

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

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SUMMARY: This amendment adopts a new airworthiness directive (AD), 
applicable to certain Boeing Model 737-300, -400, and -500 series 
airplanes. This amendment requires, for certain airplanes, replacement 
of the hinge assemblies on certain escape slide compartments of the 
forward doors with new, stronger hinge assemblies; and, for certain 
other airplanes, an inspection for incorrectly crimped hinge 
assemblies, and corrective action if necessary. The actions specified 
by this AD are intended to prevent forward door escape slides from 
falling out of their compartments into the airplane interior and 
inflating, which could impede an evacuation in the event of an 
emergency. This action is intended to address the identified unsafe 
condition.

DATES: Effective March 5, 2004.
    The incorporation by reference of a certain publication listed in 
the regulations is approved by the Director of the Federal Register as 
of March 5, 2004.

ADDRESSES: The service information referenced in this AD may be 
obtained from Boeing Commercial Airplanes, P.O. Box 3707, Seattle, 
Washington 98124-2207. This information may be examined at the Federal 
Aviation Administration (FAA), Transport Airplane Directorate, Rules 
Docket, 1601 Lind Avenue, SW., Renton, Washington; or at the Office of 
the Federal Register, 800 North Capitol Street, NW., suite 700, 
Washington, DC.

[[Page 4453]]


FOR FURTHER INFORMATION CONTACT: Keith Ladderud, Aerospace Engineer, 
Cabin Safety and Environmental Systems Branch, ANM-150S, FAA, Seattle 
Aircraft Certification Office, 1601 Lind Avenue, SW., Renton, 
Washington 98055-4056; telephone (425) 917-6435; fax (425) 917-6590.

SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal 
Aviation Regulations (14 CFR part 39) to include an airworthiness 
directive (AD) that is applicable to certain Boeing Model 737-300, -
400, and -500 series airplanes was published as a supplemental notice 
of proposed rulemaking (NPRM) in the Federal Register on September 19, 
2003 (68 FR 54869). That action proposed to require, for certain 
airplanes, replacement of the hinge assemblies on certain escape slide 
compartments of the forward doors with new, stronger hinge assemblies; 
and, for certain other airplanes, an inspection for incorrectly crimped 
hinge assemblies, and corrective action if necessary.

Comments

    Interested persons have been afforded an opportunity to participate 
in the making of this amendment. Due consideration has been given to 
the comments received.

Agrees With the Proposed AD

    One commenter generally agrees with the proposed AD and has no 
additional comments.

Allow for Reinstallation of the Hinges During Maintenance

    One commenter requests that the proposed AD be revised to allow 
reinstallation of the existing hinge assemblies if a maintenance action 
not associated with the proposed AD requires the removal of the escape 
slide/hinge assemblies. This would allow normal operations until the 
replacement of the hinge assemblies is completed per planned 
maintenance. The commenter believes paragraph (c) of the proposed AD 
prohibits normal maintenance actions that require the removal and 
reinstallation of the escape slide/hinge assemblies. The commenter 
believes their proposal would allow for normal maintenance without 
disruption while replacing the hinge assemblies within the compliance 
time of the proposed AD and without any degradation of safety.
    We agree with the commenter that clarification is necessary. The 
intent of paragraph (c) of the proposed AD is that when operators 
replace parts, they should replace them with good parts rather than bad 
parts. Doing normal maintenance where the escape slide assembly is 
removed does not warrant immediate replacement of the hinge assembly. 
By reinstalling the escape slide assembly, the operator is not 
``replacing'' the hinge assembly. The hinge assembly replacement would 
be done within the compliance time of the AD. The final rule has been 
clarified accordingly.

Conclusion

    After careful review of the available data, including the comments 
noted above, the FAA has determined that air safety and the public 
interest require the adoption of the rule with the changes previously 
described.

Cost Impact

    There are approximately 1,974 airplanes of the affected design in 
the worldwide fleet. The FAA estimates that 793 airplanes of U.S. 
registry will be affected by this AD.
    Replacement of the hinge assemblies, if necessary, will take 
approximately 5 work hours per airplane, at an average labor rate of 
$65 per work hour. Required parts will cost approximately $1,569 per 
airplane. Based on these figures, the cost impact of the hinge 
replacement is estimated to be $1,894 per airplane.
    The inspection, if necessary, will take approximately 1 to 3 work 
hours per airplane, at an average labor rate of $65 per work hour. 
Based on these figures, the cost impact of the inspection is estimated 
to be $65 to $195 per airplane.
    The cost impact figures discussed above are based on assumptions 
that no operator has yet accomplished any of the 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.

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.
    For the reasons discussed above, I certify that this action (1) is 
not a ``significant regulatory action'' under Executive Order 12866; 
(2) is not a ``significant rule'' under DOT Regulatory Policies and 
Procedures (44 FR 11034, February 26, 1979); and (3) 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 final evaluation has been prepared for this action 
and it is contained in the Rules Docket. A copy of it 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:

2004-02-08 Boeing: Amendment 39-13443. Docket 2001-NM-88-AD.

    Applicability: Model 737-300, -400, and -500 series airplanes; 
certificated in any category; as listed in Boeing Special Attention 
Service Bulletin 737-25-1430, Revision 1, dated April 10, 2003.
    Compliance: Required as indicated, unless accomplished 
previously.
    To prevent forward door escape slides from falling out of their 
compartments into the airplane interior and inflating, which could 
impede an evacuation in the event of emergency, accomplish the 
following:

Hinge Assembly Replacement

    (a) For airplanes on which the hinge assemblies have not been 
replaced as of the effective date of this AD in accordance with 
Boeing Special Attention Service Bulletin 737-25-1430, dated 
February 22, 2001: Within 36 months after the effective date of this 
AD, replace the hinge assemblies on the escape slide stowage 
compartments of the forward doors with new, stronger hinge 
assemblies, in accordance with Part 1 of the Accomplishment 
Instructions of Boeing Special Attention Service Bulletin 737-25-
1430, Revision 1, dated April 10, 2003.

Hinge Assembly Inspection

    (b) For airplanes on which the hinge assemblies were replaced 
before the effective date of this AD in accordance with Boeing

[[Page 4454]]

Special Attention Service Bulletin 737-25-1430, dated February 22, 
2001: Within 36 months after the effective date of this AD, perform 
a general visual inspection for incorrectly crimped hinge 
assemblies, in accordance with Part 2 of the Accomplishment 
Instructions of Boeing Special Attention Service Bulletin 737-25-
1430, Revision 1, dated April 10, 2003. If any hinge assembly is not 
correctly crimped, perform corrective action before further flight 
in accordance with Revision 1 of the service bulletin.

    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.''

Part Installation

    (c) As of the effective date of this AD, when replacing a hinge 
assembly, no person may install a hinge assembly, part number 
65C30431-6 or 65C30431-7, on any airplane.

Alternative Methods of Compliance

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

Incorporation by Reference

    (e) The actions shall be done in accordance with Boeing Special 
Attention Service Bulletin 737-25-1430, Revision 1, dated April 10, 
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 Airplanes, 
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 March 5, 2004.

    Issued in Renton, Washington, on January 20, 2004.
Kalene C. Yanamura,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 04-1914 Filed 1-29-04; 8:45 am]

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