[Federal Register Volume 61, Number 66 (Thursday, April 4, 1996)]
[Rules and Regulations]
[Pages 14961-14962]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-7984]



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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39

[Docket No. 95-NM-93-AD; Amendment 39-9559; AD 96-07-10]


Airworthiness Directives; Boeing Model 747-100, -200, and -300 
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 747-100, -200, and -300 series 
airplanes, that requires an inspection to determine if hinge bolts and 
nuts are installed in the overhead stowage bins, and the installation 
of hinge bolts and nuts, if necessary. This amendment is prompted by 
reports that overhead stowage bins in the passenger compartment have 
fallen out of position due to missing hinge bolts. The actions 
specified by this AD are intended to ensure that hinge bolts are 
installed in the overhead stowage bins. Missing hinge bolts could 
result in the overhead stowage bins falling out of position and 
injuring airplane occupants.

DATES: Effective May 6, 1996.

    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of May 6, 1996.

ADDRESSES: The service information referenced in this AD may be 
obtained from Boeing Commercial Airplane Group, 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.

FOR FURTHER INFORMATION CONTACT: Dorothy Lundy, Aerospace Engineer, 
Airframe Branch, ANM-120S, FAA, Transport Airplane Directorate, Seattle 
Aircraft Certification Office, 1601 Lind Avenue, SW., Renton, 
Washington; telephone (206) 227-1675; fax (206) 227-1181.

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 747-100, -
200, and -300 series airplanes was published as a supplemental notice 
of proposed rulemaking in the Federal Register on January 9, 1996 (61 
FR 634). That action proposed to require an inspection to determine if 
hinge bolts and nuts are installed in the overhead stowage bins, and 
the installation of hinge bolts and nuts, if necessary.
    Interested persons have been afforded an opportunity to participate 
in the making of this amendment. Due consideration has been given to 
the comments received.
    One commenter supports the proposed rule.
    One commenter states that the inspection required by the proposed 
rule is a relatively simple inspection, and the issuance of an AD 
should not be required. The FAA infers that the commenter requests the 
AD be withdrawn. The FAA does not concur. According to section 39.1 
(``Airworthiness Directives'') of the Federal Aviation Regulations (14 
CFR 39.1), the issuance of an AD is based on the finding that an unsafe 
condition exists or is likely to develop in aircraft of a particular 
type design. The responsibilities placed on the FAA by the Federal 
Aviation Act do not limit it from making any unsafe condition--whether 
resulting from maintenance, design defect, or otherwise--the proper 
subject of an AD. Regardless of whether the corrective action is easy 
or difficult to perform, the FAA has determined that the corrective 
action must be accomplished in order to eliminate or prevent the 
identified unsafe condition. Issuance of an AD is the appropriate 
vehicle for ensuring that the corrective action is accomplished on all 
affected airplanes.
    Another commenter states that some stowage bin support panels 
separated due to damaged honeycomb cores (the connection point for the 
hinge bolts), not due to the absence of hinge bolts, as stated in the 
proposed AD. The commenter also states that it installed an enlarged 
blade assembly on the panels, and this corrected the problem. While 
this commenter does not request that the proposed rule be changed, the 
FAA infers that the commenter is requesting that the proposed rule be 
withdrawn. In that case, the FAA does not concur. Investigation of 
damaged stowage bin support panels in service revealed that the stowage 
bin support panel separated because the hinge bolts were not installed 
during maintenance; these occurrences prompted the issuance of the 
proposed rule. Missing hinge bolts could result in the overhead stowage 
bins falling out of position and injuring airplane occupants. 
Additionally, the stowage bin support panels themselves must be in good 
condition in order to support the interface of the hinge bolts. Prudent 
operators performing the inspection of

[[Page 14962]]
the hinge bolts required by this AD would likely address any damage 
found of the honeycomb cores of the panels or any damage detected of 
the bin. The FAA has been advised that Boeing is currently developing 
service information to address the repair of the bins. When this 
information is reviewed and approved, the FAA may consider further 
rulemaking.
    One commenter requests that the compliance time for the inspection 
be extended from the proposed 90 days to 150 days. This commenter 
considers that extending it by another 60 days would allow operators to 
accomplish the inspection during regularly scheduled maintenance, and 
would prevent any disruption of service. The FAA does not concur. In 
developing the compliance time for this rulemaking action, the FAA took 
into consideration not only the safety implications associated with the 
addressed unsafe condition, but parts availability, fleet utilization 
rates, and normal maintenance schedules for the majority of affected 
operators. In consideration of these factors, the FAA finds that the 
90-day compliance time is appropriate for the one-time inspection 
required by this AD. Additionally, the AD provides ``credit'' to 
operators who have performed this inspection within the last 18 months 
prior to the effective date of the AD. However, paragraph (b) of the 
final rule does provide affected operators the opportunity to apply for 
an adjustment of the compliance time if data are presented to justify 
such an adjustment.
    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 as proposed.
    There are approximately 573 Model 747-100, -200, and -300 series 
airplanes of the affected design in the worldwide fleet. The FAA 
estimates that 157 airplanes of U.S. registry would be affected by this 
AD, that it will take approximately 1 work hour per airplane to 
accomplish the required actions, and that the average labor rate is $60 
per work hour. Based on these figures, the cost impact of the AD on 
U.S. operators is estimated to be $9,420, or $60 per airplane.
    The cost impact figure discussed above is 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 regulations adopted herein will not have substantial direct 
effects 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, in 
accordance with Executive Order 12612, it is determined that this final 
rule does not have sufficient federalism implications to warrant the 
preparation of a Federalism Assessment.
    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

    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:

96-07-10  Boeing: Amendment 39-9559. Docket 95-NM-93-AD.

    Applicability: Model 747-100, -200, and -300 series airplanes, 
as listed in Boeing Alert Service Bulletin 747-25A3095, Revision 1, 
dated September 28, 1995; certificated in any category.

    Note 1: This AD applies to each airplane identified in the 
preceding applicability provision, regardless of whether it has been 
otherwise 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 (b) 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.
    To ensure that hinge bolts are installed in the overhead stowage 
bins, accomplish the following:
    (a) Within 90 days after the effective date of this AD, unless 
accomplished previously within the last 18 months prior to the 
effective date of this AD, perform a one-time visual inspection to 
determine if hinge bolts and nuts are installed in the overhead 
stowage bins, in accordance with either Boeing Alert Service 
Bulletin 747-25A3095, dated April 27, 1995, or Revision 1, dated 
September 28, 1995.
    (1) If the hinge bolts and nuts are installed, no further action 
is required by this AD.
    (2) If any hinge bolt or nut is not installed, prior to further 
flight, install a hinge bolt and nut in accordance with either alert 
service bulletin.
    (b) 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, Transport Airplane Directorate. 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 2: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Seattle ACO.

    (c) 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.
    (d) The actions shall be done in accordance with Boeing Alert 
Service Bulletin 747-25A3095, dated April 27, 1995, or Boeing Alert 
Service Bulletin 747-25A3095, Revision 1, dated September 28, 1995. 
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.
    (e) This amendment becomes effective on May 6, 1996.

    Issued in Renton, Washington, on March 27, 1996.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 96-7984 Filed 4-3-96; 8:45 am]
BILLING CODE 4910-13-U