60810 Federal Register / Vol. 62, No. 219 / Thursday, November 13, 1997 / Proposed Rules

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.

§ 39.13 [Amended]

2. Section 39.13 is amended by

removing amendment 39–10011 (62 FR

24325, May 5, 1997), and by adding a

new airworthiness directive (AD), to

read as follows:

Boeing: Docket 97–NM–157–AD. Revises AD

97–09–15, Amendment 39–10011.

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 (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, unless

accomplished previously.

To prevent sudden uncommanded yawing

of the airplane due to potential failures

within the yaw damper system, and

consequent injury to passengers and

crewmembers, accomplish the following:

(a) Perform a one-time inspection of the

engage solenoid valve of the yaw damper on

the rudder power control unit (PCU) to

determine the part number (P/N) of the valve.

If any valve having Parker P/N 59600–5011

(Boeing P/N 10–60811–9), Parker P/N 59600–

5007 (Boeing P/N 10–60811–3), or Parker P/

N 59600–5003 (Boeing P/N 10–60811–1) is

installed, prior to further flight, replace it

with a valve having Parker P/N 881600–1001

(Boeing P/N 10–60811–13), Sterer P/N

45080–1 (Boeing P/N 10–60811–8), or Sterer

P/N 45080 (Boeing P/N 10–60811–3).

Accomplish the actions in accordance with

procedures specified in Chapter 22–11–61

(for Model 737–100 and –200 series

airplanes) or Chapter 22–12–21 (for Model

737–300, –400, and –500 series airplanes) of

the Boeing Maintenance Manual, as

applicable. Accomplish the inspection at the

earlier of the times specified in paragraphs

(a)(1) and (a)(2) of this AD.

(1) Within 5 years or 15,000 flight hours

after June 9, 1997 (the effective date of AD

97–09–15, amendment 39–10011), whichever

occurs first.

(2) At the next time the PCU is sent to a

repair facility.

Note 2: Boeing In-Service Activities Report

95–03–2725–10, dated February 16, 1995 (for

Model 737–100 and –200 series airplanes), or

95–04–2725–10, dated February 24, 1995 (for

Model 737–300, –400, and –500 series

airplanes), provides additional information

concerning interchangeability of solenoid

valve part numbers.

Note 3: Operators should note that, as

specified in paragraph (a) of this AD, both the

Parker and Sterer P/N’s have the same Boeing

P/N (10–60811–3). If, upon inspection,

Boeing P/N 10–60811–3 is found to be

installed, operators must ascertain the vendor

P/N. Parts having Boeing P/N 10–60811–3

and Parker P/N 59600–5007 must be replaced

and are not considered to be acceptable

replacement parts. In addition, some engage

solenoid valves may be labeled with only the

name ‘‘Bertea,’’ rather than ‘‘Parker’’ or

‘‘Parker-Bertea.’’

(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 4: 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.

Issued in Renton, Washington, on

November 6, 1997.

Darrell M. Pederson,

Acting Manager, Transport Airplane

Directorate, Aircraft Certification Service.

[FR Doc. 97–29820 Filed 11–12–97; 8:45 am]

BILLING CODE 4910–13–U

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).

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
Federal Register / Vol. 62, No. 219 / Thursday, November 13, 1997 / Proposed Rules 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.

§ 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
60812 Federal Register / Vol. 62, No. 219 / Thursday, November 13, 1997 / Proposed Rules

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

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