This section of the FEDERAL REGISTER

contains notices to the public of the proposed

issuance of rules and regulations. The

purpose of these notices is to give interested

persons an opportunity to participate in the

rule making prior to the adoption of the final

rules.

Proposed Rules Federal Register

18520

Vol. 61, No. 82

Friday, April 26, 1996

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 95–ANE–30]

Airworthiness Directives; Hartzell

Propeller Inc. HC–A3V, HC–B3M, HC–

B3T, HC–B4M, HC–B4T, and HC–B5M

Series Propellers

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

Hartzell Propeller Inc. (Hartzell) HC–

A3V, HC–B3M, HC–B3T, HC–B4M, HC–

B4T, and HC–B5M series propellers.

This proposal would require hub

replacement over a 10-year time period

with a concurrent blade and blade

clamp inspection. This proposal is

prompted by reports of two propeller

hub failures and one crack indication

that occurred on Mitsubishi MU–2B–60

aircraft, the similarity of construction

and load transfer paths between the

Hartzell propeller models installed on

the Mitsubishi MU–2 aircraft and

Hartzell’s 3-, 4-, and 5-bladed steel hub

propeller models, several blade shank

failures, and reports of cracks in blade

clamps. The actions specified by the

proposed AD are intended to prevent

propeller hub, blade, or blade clamp

failure, which can result in loss of

aircraft control.

DATES: Comments must be received by

June 25, 1996.

ADDRESSES: Submit comments in

triplicate to the Federal Aviation

Administration (FAA), New England

Region, Office of the Assistant Chief

Counsel, Attention: Rules Docket No.

95–ANE–30, 12 New England Executive

Park, Burlington, MA 01803–5299.

Comments may be inspected at this

location between 8:00 a.m. and 4:30

p.m., Monday through Friday, except

Federal holidays.

The service information referenced in

the proposed rule may be obtained from

Hartzell Propeller Inc., One Propeller

Place, Piqua, OH 45356–2634. This

information may be examined at the

FAA, New England Region, Office of the

Assistant Chief Counsel, 12 New

England Executive Park, Burlington,

MA.

FOR FURTHER INFORMATION CONTACT:

Tomaso DiPaolo, Aerospace Engineer,

Chicago Aircraft Certification Office,

FAA, Small Airplane Directorate, 2300

East Devon Ave., Des Plaines, IL 60018;

telephone (847) 294–7031, fax (847)

294–7834.

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

should 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

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 95–ANE–30.’’ 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, New England Region, Office of the

Assistant Chief Counsel, Attention:

Rules Docket No. 95–ANE–30, 12 New

England Executive Park, Burlington, MA

01803–5299.

Discussion

The Federal Aviation Administration

(FAA) has received reports of two hub

failures and one crack indication that

occurred on Hartzell Propeller Inc.

(Hartzell) HC–B4TN–5(D,G,J)L/

LT10282(B,K)–5.3R and HC–B4TN–

5(D,G,J)L/LT10282N(B,K)–5.3R

propellers installed on Mitsubishi MU–

2B–60 aircraft. This airworthiness

directive (AD) action is prompted by

those reports and the similarity of

construction and load transfer paths

between the Hartzell propeller models

installed on the Mitsubishi MU– 2B–60

aircraft and other Hartzell 3-, 4-, and 5-

bladed steel hub propeller model

installations. This condition, if not

corrected, could result in hub failure,

which can result in loss of aircraft

control.

The FAA has determined that the

most effective way to address all hub

strength concerns is to require propeller

hub replacement. The following are

some of the benefits of a replacement

program:

1. Improved propeller hub metallurgy;

2. Elimination of any surface

decarburization in the pilot tube bore;

3. Introduction of compressive

residual stress in the pilot tube bore;

4. Improved corrosion protection in

the pilot tube bore;

5. Improved surface finish in the pilot

tube bore.

Additionally, the referenced propeller

models have been involved in several

incidents of blade shank failures and

have been reported to have cracks in the

blade clamps. These conditions, if not

corrected, could result in blade or blade

clamp failure, which can result in loss

of aircraft control. Therefore, the FAA

has determined that a concurrent

inspection of the blades and blade

clamps at the time of hub replacement

is necessary to detect cracks in either

component.

The FAA has issued previous AD’s to

address a similar condition for specific

propeller models and aircraft

combinations. This AD, however,

addresses a broader population.

Airworthiness directive 95–01–02 is

applicable to Hartzell propeller models

HC–B4TN–5(D,G,J)L/LT10282(B,K)–

5.3R, HC–B4TN–5(D,G,J)L/
Federal Register / Vol. 61, No. 82 / Friday, April 26, 1996 / Proposed Rules 18521

LT10282N(B,K)–5.3R, and HC–B4TN–

5(D,G,J)L/LT10282NS(B,K)–5.3R

installed on Mitsubishi MU–2B– 26A,

–36A, –40, –60; MU–2B–30 modified by

Supplemental Type Certificate (STC)

SA336GL–D & SA339GL–D; MU–2B–36

Modified by STC SA2413SW and any

other MU–2 Series aircraft which have

the referenced propeller models

installed. Airworthiness directive 95–

03–03 is applicable to Hartzell propeller

models HC–B4TN–3/T10173F(N)(B,K)–

12.5 and HC–B4TN– 3A/

T10173F(N)(B,K)–12.5 installed on

Beech A100 and A100A aircraft.

Operators of the referenced propellers

and aircraft combinations must refer to

the previous AD’s for required actions.

The FAA has reviewed and approved

the technical contents of Hartzell

Propeller Inc. Manual 118F, Revision 2,

dated May 1992, pages 15 to 19 and 57

through 96, for 3- and 4-bladed hub

models, and Manual 132A, Revision 2,

dated June 1992, pages IV–5 to IV–11

and VII–1 to VII–46, for 5-bladed hub

models, that describe procedures for

disassembling and reassembling the

propeller with a new hub; Hartzell

Propeller Inc. Service Manual 202A,

Revision 3, dated June 1995, pages 201

through 215, that describes the magnetic

particle inspection procedure for the

propeller blade clamps; and Hartzell

Propeller Inc. Service Bulletin No.

136H, dated March 12, 1993, that

describes inspection procedures for the

propeller blade bearing bores.

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, over a 10-year time period,

propeller hub replacement with a

concurrent blade and blade clamp

inspection for Hartzell Propeller Inc.

Models HC–A3VF–7 ( ), HC–B3TF–7( ),

HC–B3MN–3( ), HC–B3TN–2( ), HC–

B3TN–3( ), HC–B3TN–5 ( ), HC–B4MN–

5( ), HC–B4MP–3( ), HC–B4TN–3( ),

HC–B4TN–5( ), HC–B5MA–3( ), HC–

B5MP–3( ), HC–B5MP–5( ), HC–B3MN–

5( ), HC– B3TN–4( ), HC–B4MP–4( ),

and HC–B5MN–3( ) propellers. This

propeller hub replacement program has

been scheduled to require replacement

of the most aged propeller hubs first.

Additionally, the replacement program

will accelerate the replacement of the 4

and 5 blade propeller hubs, while still

replacing the 3 blade propeller hubs,

with completion of the program in 10

years. Hartzell Propeller Inc. has

advised the FAA that they will provide

new hubs at special prices for the

duration of this AD program. The

actions would be required to be

accomplished in accordance with the

service documents described

previously.

There are approximately 24,320

propellers of the affected design in the

worldwide fleet. The FAA estimates that

50% of the subject propellers are

installed on aircraft of U.S. registry and

that 75% will have the work done

during normally scheduled propeller

maintenance. For those who accomplish

the AD action during normal propeller

maintenance, the parts cost will average

$1,955 with no additional labor. For

those who accomplish the AD action by

itself, the parts cost will average $2,174,

plus approximately 27 work hours per

propeller at an average labor rate of $60

per work hour. Based on these figures,

the total cost impact on U.S. operators

is estimated to be $29,363,360. The cost

will vary between the 3-, 4-, and 5-

bladed propeller configurations and the

above data represents an average cost.

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:

Hartzell Propeller Inc.: Docket No. 95–ANE–

30.

Applicability: Hartzell Propeller Inc.

(Hartzell) Models HC–A3VF–7( ), HC–B3TF–

7( ), HC–B3MN–3( ), HC–B3TN–2( ), HC–

B3TN–3( ), HC–B3TN–5 ( ), HC–B4MN–5( ),

HC–B4MP–3( ), HC–B4TN–3( ), HC–B4TN–5(

), HC–B5MA–3( ), HC–B5MP–3( ), HC–

B5MP–5( ), HC–B3MN–5( ), HC–B3TN–4( ),

HC–B4MP–4( ), and HC–B5MN–3( )

propellers. These propellers are installed on

but not limited to the following aircraft:

Aerospace Technologies of Australia PTY

LTD N22B, N24A, N22S; Air Tractor, Inc.

AT–301, AT–302, AT–400, AT–400A, AT–

401, AT–402, AT–502, AT–503, AT–802;

Agusta S.p.A. SF600, F.260;

Ayres Corporation S–2R, S2R–T11, S2R–T15,

S2R–T34, S2R–T56, S2RHG–T65;

Beech A36, 65–90, 65–90A, C90, B90, E90,

C90A, F90, 100, 200, 200C, A200C, B200,

B200C, 200T, 200CT, A200CT, B200T,

B200CT, 65–80, 65–A90–1, 65–A90–2, 65–

A90–4, 99, 99A, A99A, B99, A200, C99,

H90, 300, 300LW, B300, B300C, 1900,

1900C, T34C, T34C–1;

Cessna 208, 208A, 208B, 421, 425, 441, 402,

P210N;

Construcciones Aeronauticas, S.A. (CASA)

C–212–CB, –CC, –CE, –CF;

deHavilland Aircraft Co., Ltd. D.H.114;

deHavilland Inc. DHC–2, DHC–3, DHC–4;

DHC–6, 1, 100, 200, 300;

Empresa Brasileira de Aeronautica S/A

Embraer EMB–110P1, EMB–110P2;

Fairchild Aircraft, Inc. SA26–AT, –T;

SA226–AT, –TB;

Frakes Aviation (Gulfstream American ) G–

73;

Great Lakes Aircraft Co. 2T–1A;

Helio HST–550, HST–550A;

Industrie Aeronautiche e Meccaniche Piaggio

P.166DL3;

Israel Aircraft Industries, Ltd. Arava 101,

101B;

McDonnell Douglas DC–3 series;

McKinnon Enterprises, Inc. (Grumman) G–

21E, G21–G;

Mitsubishi MU–2B series;

Pacific Aerospace Corporation, Ltd. FU24–

954, FU2A–954;

Partenavia Costruzioni Aeronautiche S.p.A.

AP68TP 300, AP68TP 600;

Pilatus Aircraft Ltd. PC–6/A–H2, /B1–H2,

/B–H2, /B2–H2, /B2–H4, PC–7;

Piper Aircraft Corporation PA31–T1, –T2,

–T3; PA31P; PA42, –42–720, –42–720R;

Prop-Jets, Inc., Interceptor (Aero

Commander) (Meyers) 400;

Schweizer Aircraft Corp. (Grumman) G–

164A, G–164B, G–164B–34T, –15T; G–

164D;

Short Bros. Limited & Harland Ltd. SC–7

series, SD3 series;
18522 Federal Register / Vol. 61, No. 82 / Friday, April 26, 1996 / Proposed Rules

Twin Commander Aircraft Corp. 680T, V,

681, 690A, 690B, 690C, 695, 695A;

Weatherly Aviation Company 620TP.

Note 1: The parenthesis that appear in the

propeller models indicate the presence or

absence of additional letter(s) which vary the

basic propeller hub model designation. This

airworthiness directive (AD) is applicable

regardless of whether these letters are present

or absent on the propeller hub model

designation.

Note 2: The above is not a complete list of

aircraft which may contain the affected

Hartzell Propeller Inc. Models HC–A3VF–7

( ), HC–B3TF–7( ), HC–B3MN–3( ), HC–

B3TN–2( ), HC–B3TN–3( ), HC–3TN–5( ),

HC–B4MN–5( ), HC–B4MP–3( ), HC–B4TN–

3( ), HC–B4TN–5( ), HC–B5MA–3( ), HC–

B5MP–3( ), HC–B5MP–5( ), HC–B3MN–5( ),

HC–B3TN–4( ), HC–B4MP–4( ), and HC–

B5MN–3( ) propellers because of installation

approvals made by, for example,

Supplemental Type Certificate or field

approval under FAA Form 337 ‘‘Major Repair

and Alteration.’’ It is the responsibility of the

owner, operator, and person returning the

aircraft to service to determine if an aircraft

has an affected propeller.

Note 3: This AD applies to each propeller

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

propellers that have been modified, altered,

or repaired so that the performance of the

requirements of this AD is affected, the

owner/operator must use the authority

provided in paragraph (h) to request approval

from the Federal Aviation Administration

(FAA). This approval may address either no

action, if the current configuration eliminates

the unsafe condition, or different actions

necessary to address the unsafe condition

described in this AD. Such a request should

include an assessment of the effect of the

changed configuration on the unsafe

condition addressed by this AD. In no case

does the presence of any modification,

alteration, or repair remove any propeller

from the applicability of this AD.

Compliance: Required as indicated, unless

accomplished previously.

To prevent propeller hub, blade, or blade

clamp failure, which can result in loss of

aircraft control, accomplish the following:

(a) This AD requires no action for operators

with Hartzell propeller models HC–B4TN–

5(D,G,J)L/LT10282(B,K)–5.3R, HC–B4TN–

5(D,G,J)L/LT10282N(B,K)–5.3R, and HC–

B4TN–5(D,G,J)L/LT10282NS(B,K)–5.3R

installed on Mitsubishi MU–2B– 26A, –36A,

–40, –60; MU–2B–30 modified by

Supplemental Type Certificate (STC)

SA336GL–D & SA339GL–D; MU–2B–36

Modified by STC SA2413SW and any other

MU–2 Series aircraft which have the

referenced propeller models installed. These

operators must, however, comply with AD

95–01–02.

(b) This AD requires no action for operators

with Hartzell propeller models HC–B4TN–3/

T10173F(N)(B,K)–12.5 and HC–B4TN–3A/

T10173F(N)(B,K)–12.5 installed on Beech

A100 and A100A aircraft. These operators

must, however, comply with AD 95–03–03.

(c) Disassemble the propeller in accordance

with Hartzell Propeller Inc. Service Manual

118F, Revision 2, dated May 1992, pages 15

to 19, for 3- and 4-bladed hub models, and

Service Manual 132A, Revision 2, dated June

1992, pages IV–5 to IV–11, for 5-bladed hub

models, remove the hub from service, and

replace the hub with a serviceable hub in

accordance with the compliance schedule in

Table 1 of this AD.

(1) Utilize Table 1 of this AD in accordance

with the following example: Model HC–

B3TN–3( ) series propellers, starting with

serial numbers (S/N’s) BU1 through BU377,

require replacement before the end of

December of calendar year 1996. Serial

numbers BU378 through BU754 require hub

replacement before the end of June of

calendar year 1997, and so forth.

(2) The affected hubs can only be replaced

with serviceable hubs having a S/N not listed

in Table 1 of this AD for that propeller

model, or serviceable hubs having a S/N for

which replacement is not yet required in

accordance with Table 1 of this AD.

(3) Some existing propeller hub S/N’s

include a suffix letter, such as an ‘‘A.’’ The

presence or absence of this letter has no

significance in determining compliance.

(4) Since a hub may be used in various

propeller models, the S/N and the model

number shown in Table 1 of this AD may not

coincide. Precedence is given to the hub S/

N in determining compliance requirements.

The hub model is only given as a reference.

(5) Hub replacement must be accomplished

by the end of the calendar month indicated

at the top of the appropriate column in Table

1 of this AD. The S/N ranges in this table

identify the propeller hubs that require

replacement by the end of that month.

BILLING CODE 4190–13–P
Federal Register / Vol. 61, No. 82 / Friday, April 26, 1996 / Proposed Rules 18523

Table 1

BILLING CODE 4910–13–C
18524 Federal Register / Vol. 61, No. 82 / Friday, April 26, 1996 / Proposed Rules

(d) Perform a fluorescent penetrant

inspection of blades for cracks in accordance

with Hartzell Propeller Inc. Service Bulletin

136H, dated March 12, 1993, prior to

installing a serviceable hub.

(e) Perform magnetic particle inspection of

blade clamps for cracks in accordance with

Hartzell Service Manual 202A, Revision 3,

dated June 1995, pages 201 to 215, prior to

installing a serviceable hub.

(f) If cracks are found in either the blade

or the blade clamps, prior to further flight

replace with serviceable blade or blade

clamps.

(g) Reassemble the propeller in accordance

with Hartzell Propeller Inc. Service Manual

118F, Revision 2, dated May 1992, pages 57

through 96, for 3- and 4-bladed hub models,

and Service Manual 132A, Revision 2, dated

June 1992, pages VII–1 to –46, for 5-blade

hub models.

(h) 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, Chicago

Aircraft Certification Office. The request

should be forwarded through an appropriate

FAA Principal Maintenance Inspector, who

may add comments and then send it to the

Manager, Chicago Aircraft Certification

Office.

Note: Information concerning the existence

of approved alternative methods of

compliance with this airworthiness directive,

if any, may be obtained from the Chicago

Aircraft Certification Office.

(i) 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 aircraft to

a location where the requirements of this AD

can be accomplished.

Issued in Burlington, Massachusetts, on

April 16, 1996.

Jay J. Pardee,

Manager, Engine and Propeller Directorate,

Aircraft Certification Service.

[FR Doc. 96–10060 Filed 4–25–96; 8:45 am]

BILLING CODE 4910–13–P

14 CFR Part 39

[Docket No. 94–CE–22–AD]

RIN 2120–AA64

Airworthiness Directives; Fairchild

Aircraft SA26, SA226, and SA227

Series Airplanes

AGENCY: Federal Aviation

Administration, DOT.

ACTION: Supplemental notice of

proposed rulemaking (NPRM);

Reopening of the comment period.

SUMMARY: This document proposes to

revise an earlier proposed airworthiness

directive (AD), which would have

superseded AD 93–19–06. That AD

currently requires repetitively

inspecting acrylic cabin and cockpit

side windows for cracks on certain

Fairchild Aircraft SA26, SA226, and

SA227 series airplanes, and, if cracks

are found that exceed certain

limitations, replacing that window. The

previous document included the

following: the proposed requirement of

modifying certain cockpit side

windows; more fully-defined crack

limitations; and more clear repetitive

inspection intervals for the affected

airplanes over those included in AD 93–

19–06. Comments received regarding

the NPRM have prompted the Federal

Aviation Administration to change the

proposal and allow the public a further

opportunity to participate in the

rulemaking process. The actions

specified by the proposed AD are

intended to prevent acrylic cabin or

cockpit side window failures, which, if

not detected and corrected, could result

in airframe damage and decompression

injuries.

DATES: Comments must be received on

or before June 24, 1996.

ADDRESSES: Submit comments in

triplicate to the Federal Aviation

Administration (FAA), Central Region,

Office of the Assistant Chief Counsel,

Attention: Rules Docket No. 94–CE–22–

AD, Room 1558, 601 E. 12th Street,

Kansas City, Missouri 64106. Comments

may be inspected at this location

between 8 a.m. and 4 p.m., Monday

through Friday, holidays excepted.

Service information that applies to the

proposed AD may be obtained from

Fairchild Aircraft, P.O. Box 790490, San

Antonio, Texas 78279–0490; telephone

(210) 824–9421. This information also

may be examined at the Rules Docket at

the address above.

FOR FURTHER INFORMATION CONTACT:

Mr. Hung Viet Nguyen, Aerospace

Engineer, FAA, Airplane Certification

Office, 2601 Meacham Boulevard, Fort

Worth, Texas 76193–0150; telephone

(817) 222–5155; facsimile (817) 222–

5960.

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

should 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 that

summarizes each FAA-public contact

concerned with the substance of this

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 No. 94–CE–22–AD.’’ The

postcard will be date stamped and

returned to the commenter.

Availability of Supplemental NPRM

Any person may obtain a copy of this

supplemental NPRM by submitting a

request to the FAA, Central Region,

Office of the Assistant Chief Counsel,

Attention: Rules Docket No. 94–CE–22–

AD, Room 1558, 601 E. 12th Street,

Kansas City, Missouri 64106.

Discussion

A proposal to amend part 39 of the

Federal Aviation Regulations (14 CFR

part 39) to include an AD that would

apply to certain Fairchild Aircraft SA26,

SA226, and SA227 series airplanes was

published in the Federal Register on

February 21, 1995 (60 FR 9649). The

action proposed to supersede AD 93–

19–06 with a new AD that would

maintain the requirement of repetitively

inspecting acrylic cabin and cockpit

side windows for cracks, and replacing

any window where cracks are found

that exceed certain limitations. That

NPRM proposed to require modifying

windows that do not have inner

window panes installed.

Accomplishment of the modification

proposed in the NPRM would be in

accordance with the following service

bulletins (SB), as applicable:

Page No. Date

Fairchild SB 26–56–10–045, which incorporates the following pages and revision levels:

3, 4, 5, and 9 ......................................................................................................................................................... Revised: December 1, 1994.