[Federal Register Volume 62, Number 219 (Thursday, November 13, 1997)]
[Proposed Rules]
[Pages 60810-60812]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-29819]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 97-NM-238-AD]
RIN 2120-AA64
Airworthiness Directives; Boeing Model 737-100, -200, -300, -400,
and -500 Series Airplanes
AGENCY: Federal Aviation Administration, DOT.
ACTION: Notice of proposed rulemaking (NPRM).
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SUMMARY: This document proposes the adoption of a new airworthiness
directive (AD) that is applicable to all Boeing Model 737-100, -200, -
300, -400, and -500 series airplanes. This proposal would 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. This proposal also would require installation
of an isolation valve in the drain line downstream of the selector
valve. This proposal 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 the proposed AD are intended to prevent damage to the
engines, airframe, or horizontal stabilizer, and/or prevent a hazard to
persons or property on the ground, as a result of ice that could
dislodge from the airplane.
DATES: Comments must be received by December 29, 1997.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), Transport Airplane Directorate, ANM-103,
Attention: Rules Docket No. 97-NM-238-AD, 1601 Lind Avenue, SW.,
Renton, Washington 98055-4056. Comments may be inspected at this
location between 9:00 a.m. and 3:00 p.m., Monday through Friday, except
Federal holidays.
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:
Comments Invited
Interested persons are invited to participate in the making of the
proposed 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 above. All
communications received on or before the closing date for comments,
specified above, will be considered before taking action on the
proposed rule. The proposals contained in this notice may be changed in
light of the comments received.
Comments are specifically invited on the overall regulatory,
economic, environmental, and energy aspects of the proposed 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 summarizing each FAA-public contact concerned with
the substance of this
[[Page 60811]]
proposal will be filed in the Rules Docket.
Commenters wishing the FAA to acknowledge receipt of their comments
submitted in response to this notice must submit a self-addressed,
stamped postcard on which the following statement is made: ``Comments
to Docket Number 97-NM-238-AD.'' The postcard will be date stamped and
returned to the commenter.
Availability of NPRMs
Any person may obtain a copy of this NPRM by submitting a request
to the FAA, Transport Airplane Directorate, ANM-103, Attention: Rules
Docket No. 97-NM-238-AD, 1601 Lind Avenue, SW., Renton, Washington
98055-4056.
Discussion
The FAA has received several reports that ice has formed on the
skin of Boeing Model 737 series airplanes due to drainage of potable
water through an incorrectly positioned selector valve for the forward
lavatory water supply. Two of these incidents resulted in engine
flameout and two other incidents resulted in damage to the horizontal
stabilizer.
The selector valve is a three-position (``DRAIN,'' ``SUPPLY,'' and
``SHUTOFF'') selector valve for the forward lavatory water supply. It
is possible to place the selector valve in the ``DRAIN'' position
instead of the ``SHUTOFF'' position during flight, which results in the
contents of the potable water supply tank draining onto the skin of the
airplane. This condition, if not corrected, could result in the
formation of ice that could dislodge from the airplane and,
consequently, cause damage to the engines, airframe, or horizontal
stabilizer and/or pose a hazard to persons or property on the ground.
Explanation of Requirements of Proposed Rule
Since an unsafe condition has been identified that is likely to
exist or develop on other products of this same type design, the
proposed AD would require installation of a placard to warn the cabin
crew not to put the selector valve for the forward lavatory water
supply in the ``DRAIN'' position during flight. In addition, the
proposed AD would require installation of an isolation valve in the
drain line downstream of the selector valve. These actions would be
required to be accomplished in accordance with a method approved by the
FAA.
Cost Impact
There are approximately 2,830 Boeing Model 737-100, -200, -300, -
400, and -500 series airplanes of the affected design in the worldwide
fleet. The FAA estimates that 1,037 airplanes of U.S. registry would be
affected by this proposed AD.
It would take approximately 1 work hour per airplane to accomplish
the proposed placard installation, at an average labor rate of $60 per
work hour. Based on these figures, the cost impact of this installation
proposed by this AD on U.S. operators is estimated to be $62,220, or
$60 per airplane.
It would take approximately 6 work hours per airplane to accomplish
the proposed installation of an isolation valve, and that the average
labor rate is $60 per work hour. Required parts would cost
approximately $300 per airplane. Based on these figures, the cost
impact of this installation proposed 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 proposed 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 proposed herein would 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
proposal would not have sufficient federalism implications to warrant
the preparation of a Federalism Assessment.
For the reasons discussed above, I certify that this proposed
regulation (1) is not a ``significant regulatory action'' under
Executive Order 12866; (2) is not a ``significant rule'' under the DOT
Regulatory Policies and Procedures (44 FR 11034, February 26, 1979);
and (3) if promulgated, 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 copy of the draft
regulatory evaluation prepared for this action is contained in the
Rules Docket. A copy of it may be obtained by contacting the Rules
Docket at the location provided under the caption ADDRESSES.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Safety.
The Proposed Amendment
Accordingly, pursuant to the authority delegated to me by the
Administrator, the Federal Aviation Administration proposes to amend
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:
Boeing: Docket 97-NM-238-AD.
Applicability: All Model 737-100, -200, -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
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 (c) 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 a hazard to persons or property on the ground,
accomplish the following:
(a) Within 6 months after the effective date of this AD, install
a placard (as shown in Figure 1 of this AD) 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 a method approved by the Manager,
Seattle Aircraft Certification Office (ACO), FAA, Transport Airplane
Directorate.
(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 ACO.
(c) 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
[[Page 60812]]
compliance with this AD, if any, may be obtained from the Seattle
ACO.
(d) 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.
BILLING CODE 4910-13-U
[GRAPHIC] [TIFF OMITTED] TP13NO97.024
Issued in Renton, Washington, on November 6, 1997.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 97-29819 Filed 11-12-97; 8:45 am]
BILLING CODE 4910-13-C
