[Federal Register Volume 64, Number 5 (Friday, January 8, 1999)]
[Rules and Regulations]
[Pages 1112-1114]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-185]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 97-NM-238-AD; Amendment 39-10981; AD 99-01-16]
RIN 2120-AA64
Airworthiness Directives; Boeing Model 737-100, -200, -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 737-100, -200, -300, -400, and -500
series airplanes, that requires installation of a placard that warns
the cabin crew not to put the selector valve for the forward lavatory
water supply in the ``DRAIN'' position during flight. This amendment
also requires installation of an isolation valve in the drain line
downstream of the selector valve, which would terminate the requirement
for the placard installation. This amendment is prompted by reports of
damage to the horizontal stabilizer, and engine flameout caused by ice
formed from water drained inadvertently through a mispositioned
selector valve. The actions specified by this AD are intended to
prevent damage to the engines, airframe, or horizontal stabilizer, and/
or to prevent a hazard to persons or property on the ground, as a
result of ice that could dislodge from the airplane.
DATES: Effective February 12, 1999.
The incorporation by reference of certain publications listed in
the regulations is approved by the Director of the Federal Register as
of February 12, 1999.
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 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: Don Eiford, Aerospace Engineer,
Systems and Equipment Branch, ANM-130S, FAA, Transport Airplane
Directorate, Seattle Aircraft Certification Office, 1601 Lind Avenue,
SW., Renton, Washington 98055-4056; telephone (425) 227-2788; fax (425)
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 all Boeing Model 737-100, -200, -
300, -400, and -500 series airplanes was published in the Federal
Register on November 13, 1997 (62 FR 60810). That action proposed to
require installation of a placard that warns the cabin crew not to put
the selector valve for the forward lavatory water supply in the
``DRAIN'' position during flight. That action also proposed to require
installation of an isolation valve in the drain line downstream of the
selector valve.
Consideration of Comments Received
Interested persons have been afforded an opportunity to participate
in the making of this amendment. Due consideration has been given to
the comments received.
Request To Delay Issuance of AD Pending Release of Service
Information
Several commenters request delay of the issuance of the AD pending
the release of appropriate service information that provides technical
details for installation of the isolation valve. The commenters state
that, without such service information, they are unable to provide
meaningful comments regarding the technical content of the proposed AD.
The FAA partially concurs with the commenter's request. The FAA
recognizes that a service bulletin would provide technical details and
procedures for accomplishing the actions proposed by the notice of
proposed rulemaking (NPRM). However, the issue subject to public
comment was the general requirement for the placard and valve
installations. Further, because the valve installation is not expected
to be technically complicated or difficult to accomplish, the FAA does
not anticipate receiving any comments addressing the technical aspects
of the valve installation. In light of this information, the FAA has
determined that it is unnecessary to delay issuance of the final rule.
Request To Revise Applicability
One commenter states its understanding of the applicability as
[[Page 1113]]
being limited to those models on which forward lavatories are
installed.
The FAA infers that the commenter is requesting that the FAA revise
the applicability to include that limitation. The FAA concurs with the
commenter's request, having determined that an affected airplane
without a forward lavatory installed would not be subject to the
identified unsafe condition. The applicability of the final rule has
been revised accordingly.
Request To Consider Valve Installation as Terminating Action
One commenter requests that the proposed AD be revised to require
installation initially of either the placard or the valve. That
commenter considers the valve installation as the primary solution to
address the identified unsafe condition; therefore, valve installation
(if accomplished within the compliance time required for the placard
installation) would preclude the need for the placard installation.
That commenter suggests some airlines may choose to incorporate the
valves within the 6-month window and forgo the placard installation. As
further justification for its request, the commenter adds that
production airplanes now include the isolation valve but not the
placard.
The FAA concurs with the request to require installation initially
of either the placard or the valve. The FAA's intent behind
installation of a placard, as proposed by the NPRM, was to provide an
expeditious means to achieve an acceptable level of safety pending
installation of the isolation valve. However, the FAA agrees that the
isolation valve is considered the primary design solution to the
identified unsafe condition. Therefore, the placard would not be needed
if the valve is installed within the 6-month compliance time required
to install the placard. The final rule has been revised to specify
this, and to indicate that installation of the valve terminates the
requirement for installation of the placard.
Request To Remove Requirement for Valve Installation
One commenter reports that it has not experienced the problem
addressed in the proposed AD. The commenter states that the proposed
requirement to install an isolation valve in the drain line is
unnecessary, and installation of a placard should be sufficient to
address the unsafe condition.
The FAA infers that the commenter is requesting removal of the
requirement to install the valve. The FAA does not concur. The FAA has
determined that long-term continued operational safety will be better
assured by design changes to remove the source of the problem, rather
than by reliance on the cabin crew following additional procedures.
This determination, coupled with a better understanding of the human
factors associated with following such procedures, has led the FAA to
consider placing less emphasis on the use of informational placards and
more emphasis on design improvements. The valve installation
requirement is in consonance with these conditions. No change to the
final rule in this regard is necessary.
Concern Regarding AD Effectiveness
One commenter generally supports the proposal, but urges the FAA to
continue to monitor occurrences of airframe damage and engine flameout
due to inadvertent or erroneous drain valve activation in flight. The
commenter states that the proposed corrective action would reduce but
not eliminate the possibility of this unsafe condition, and urges the
FAA to determine if a more active means of preventing the unsafe
condition would be appropriate.
The FAA acknowledges the commenter's concern and will continue to
monitor such occurrences of airframe damage and engine flameout. The
FAA may consider further rulemaking activity if additional corrective
actions are deemed necessary.
Actions Since Issuance of NPRM
Since the issuance of the NPRM, the FAA has reviewed and approved
Boeing Service Bulletin 737-38-1043, dated January 8, 1998, which
provides procedures for the installation of the placard. Paragraph (a)
of the final rule has been revised to incorporate the service bulletin
as the appropriate source of service information for the placard
installation. In addition, Figure 1 of the NPRM (which depicts the
placard) has been removed from the final rule because an appropriate
figure is provided in the service bulletin.
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 described
previously. The FAA has determined that these changes will neither
increase the economic burden on any operator nor increase the scope of
the AD.
Cost Impact
There are approximately 2,830 airplanes of the affected design in
the worldwide fleet. The FAA estimates that 1,037 airplanes of U.S.
registry will be affected by this AD.
It will take approximately 1 work hour per airplane to accomplish
the required placard installation, at an average labor rate of $60 per
work hour. Based on these figures, the cost impact of this installation
required by this AD on U.S. operators is estimated to be $62,220, or
$60 per airplane.
It will take approximately 6 work hours per airplane to accomplish
the required installation of an isolation valve, at an average labor
rate of $60 per work hour. Required parts will cost approximately $300
per airplane. Based on these figures, the cost impact of this
installation required by this AD on U.S. operators is estimated to be
$684,420, or $660 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.
Regulatory Impact
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 section (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 obtain
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.
[[Page 1114]]
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:
99-01-16 Boeing: Amendment 39-10981. Docket 97-NM-238-AD.
Applicability: Model 737-100, -200, -300, -400, and -500 series
airplanes; having forward lavatories installed; 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 damage to the engines, airframe, or horizontal
stabilizer, and/or to prevent a hazard to persons or property on the
ground, accomplish the following:
(a) Except as provided by paragraph (c) of this AD: Within 6
months after the effective date of this AD, install a placard on the
door beneath the forward lavatory sink, that warns the cabin crew
not to put the selector valve for the forward lavatory water supply
in the ``DRAIN'' position during flight. The installation shall be
accomplished in accordance with Boeing Service Bulletin 737-38-1043,
dated January 8, 1998.
(b) Within 36 months after the effective date of this AD,
install an isolation valve in the drain line downstream of the
selector valve for the forward lavatory water supply, in accordance
with a method approved by the Manager, Seattle Aircraft
Certification Office (ACO), FAA, Transport Airplane Directorate.
Once the valve is installed, the placard described in paragraph (a)
of this AD may be removed.
(c) For airplanes on which the valve installation required by
paragraph (b) of this AD is accomplished within the compliance time
specified in paragraph (a) of this AD, the placard installation
required by paragraph (a) is not required.
(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 ACO. 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.
(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.
(f) The placard installation shall be done in accordance with
Boeing Service Bulletin 737-38-1043, dated January 8, 1998. 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.
(g) This amendment becomes effective on February 12, 1999.
Issued in Renton, Washington, on December 30, 1998.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 99-185 Filed 1-7-99; 8:45 am]
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