27452 Federal Register / Vol. 63, No. 96 /Tuesday, May 19, 1998 /Rules and Regulations

Document No. Pages Date

TFE731–A73–5111 ........................................................................................................................................ 1–8 ................... April 16, 1998.

Total pages: 8.

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 AlliedSignal Aerospace Services Attn:

Data Distribution, M/S 64–3/2101–201, P.O.

Box 29003, Phoenix, AZ 85038–9003;

telephone (602) 365–2493, fax (602) 365–

5577. Copies may be inspected at the FAA,

New England Region, Office of the Regional

Counsel, 12 New England Executive Park,

Burlington, MA; or at the Office of the

Federal Register, 800 North Capitol Street,

NW., suite 700, Washington, DC.

(e) This amendment becomes effective on

May 19, 1998.

Issued in Burlington, Massachusetts, on

May 7, 1998.

Thomas A. Boudreau,

Acting Manager, Engine and Propeller

Directorate, Aircraft Certification Service.

[FR Doc. 98–12917 Filed 5–18–98; 8:45 am]

BILLING CODE 4910–13–U

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 97–ANE–54–AD; Amendment

39–10523, AD 98–10–11]

RIN 2120–AA64

Airworthiness Directives; CFM

International CFM56–3, –3B, –3C, –5,

–5B, and –5C Series Turbofan Engines

AGENCY: Federal Aviation

Administration, DOT.

ACTION: Final rule; request for

comments.

SUMMARY: This amendment adopts a

new airworthiness directive (AD) that is

applicable to CFM International

CFM56–3, –3B, –3C, –5, –5B, and –5C

series turbofan engines. This action

supersedes telegraphic AD T97–25–51

that currently requires removal of one

engine from an aircraft, and replacement

with a serviceable engine or

replacement of parts, if both engines are

equipped with a specific accessory

gearbox (AGB) starter gearshaft or

transfer gearbox (TGB) input bevel gear,

and daily checks of the AGB/TGB

magnetic chip detector. This

amendment is prompted by further

investigation that has revealed that

certain TGB output bevel gears and AGB

intermediate gear assemblies on

CFM56–3, –3B, and –3C series engines,

and AGB gearshaft cluster spur

assemblies on CFM56–5, –5B, and –5C

series engines could also be affected.

The actions specified by this AD are

intended to prevent inflight engine

shutdowns due to an AGB starter

gearshaft, TGB input bevel gear, TGB

output bevel gear, AGB gearshaft cluster

spur assembly or AGB intermediate gear

assembly failure.

DATES: Effective June 3, 1998.

The incorporation by reference of

certain publications listed in the

regulations is approved by the Director

of the Federal Register as of June 3,

1998.

Comments for inclusion in the Rules

Docket must be received on or before

July 20, 1998.

ADDRESSES: Submit comments in

triplicate to the Federal Aviation

Administration (FAA), New England

Region, Office of the Regional Counsel,

Attention: Rules Docket No. 97–ANE–

54–AD, 12 New England Executive Park,

Burlington, MA 01803–5299. Comments

may also be sent via the Internet using

the following address: ‘‘9-adengineprop@faa.dot.gov’’. Comments

sent via the Internet must contain the

docket number in the subject line.

The service information referenced in

this AD may be obtained from CFM

International, Technical Publications

Department, 1 Neumann Way,

Cincinnati, OH 45215; telephone (513)

552–2981, fax (513) 552–2816. This

information may be examined at the

FAA, New England Region, Office of the

Regional Counsel, 12 New England

Executive Park, Burlington, MA; or at

the Office of the Federal Register, 800

North Capitol Street, NW., suite 700,

Washington, DC.

FOR FURTHER INFORMATION CONTACT:

Glorianne Messemer, Aerospace

Engineer, Engine Certification Office,

FAA, Engine and Propeller Directorate,

12 New England Executive Park,

Burlington, MA 01803–5299; Telephone

(781) 238–7132, Fax (781) 238–7199.

SUPPLEMENTARY INFORMATION: On

December 4, 1997, the Federal Aviation

Administration (FAA) issued

telegraphic airworthiness directive (AD)

T97–25–51, applicable to CFM

International (CFMI) CFM56–3, –3B,

and –3C series turbofan series engines,

which requires removal of one engine

from an aircraft, and replacement with

a serviceable engine or replacement of

parts, if both engines are equipped with

a specific accessory gearbox (AGB)

starter gearshaft or transfer gearbox

(TGB) input bevel gear. In addition, that

telegraphic AD requires daily checks of

the AGB/TGB magnetic chip detector on

engines identified by engine serial

number (ESN) in the applicability

section of that telegraphic AD until

installation of a serviceable starter

gearshaft or input bevel gear. That

action was prompted by reports of three

inflight engine shutdowns due to AGB

starter gearshaft failures, and reports of

four findings of TGB input bevel gear

cracks that were detected during

inspections. All seven reports occurred

on low time newly delivered CFM56–3

series turbofan engines. The engines

involved in these reports had time in

service since new ranging from 213 to

500 hours, and cycles in service since

new ranging from 153 to 229.

Preliminary investigation results

indicate that the root cause of the AGB

starter gearshaft failure and TGB input

bevel gear cracks may stem from the

improper cleaning procedure prior to

the black oxide process during

manufacture that causes residual

stresses around the welding areas that

could lead to a crack. That condition, if

not corrected, could result in inflight

engine shutdowns due to an AGB starter

gearshaft or TGB input bevel gear

failure.

Since the issuance of that telegraphic

AD, the FAA has determined that

certain TGB output bevel gears and AGB

intermediate gear assemblies on

CFM56–3, –3B, and –3C series engines,

and AGB gearshaft cluster spur

assemblies on CFM56–5, –5B, and –5C

series engines could also be affected.

There are 44 total AGB starter

gearshafts, 41 total TGB input bevel

gears, 33 total TGB output bevel gears,

60 total AGB gearshaft cluster spur

assemblies, and 37 AGB intermediate

gear assemblies that may be affected.

Therefore, this expands the applicability

of the AD to include those engines with

these parts installed.

The FAA has reviewed and approved

the technical contents of CFMI CFM56–

3/–3B/–3C Alert Service Bulletin (ASB)

No. 72–A861, Revision 3, dated

December 3, 1997, that describes

procedures for AGB/TGB magnetic chip

detector inspections. In addition, the

FAA has reviewed and approved the

technical contents of CFMI CFM56–3/–

3B/–3C Service Bulletin (SB) No. 72–

863, Revision 1, dated November 18,

1997; CFMI CFM56–3/–3B/–3C SB No.

72–865, dated November 18, 1997;
Federal Register / Vol. 63, No. 96 /Tuesday, May 19, 1998 /Rules and Regulations 27453

CFMI CFM56–3/–3B/–3C SB No. 72–

867, dated November 28, 1997; CFMI

CFM56–3/–3B/–3C SB No. 72–873

Revision 1, dated February 5, 1998;

CFMI CFM56–5 SB No. 72–523,

Revision 1, dated January 30, 1998;

CFMI CFM56–5B SB No. 72–211,

Revision 1, dated January 29, 1998; and

CFMI CFM56–5C SB No. 72–350,

Revision 1, dated January 30, 1998.

These SBs describe procedures for

removal and replacement of the AGB

starter gearshaft, TGB assembly, TGB

input bevel gear, TGB output bevel gear,

AGB gearshaft cluster spur assembly or

AGB intermediate gear assembly.

Since an unsafe condition has been

identified that is likely to exist or

develop on other engines of this same

type design, this AD supersedes

telegraphic AD T97–25–51 to require

the removal of one engine on twin

engine aircraft, and replacement with a

serviceable engine or replacement of

parts, if both engines are equipped with

a specific AGB starter gearshaft, TGB

input bevel gear, TGB output bevel gear,

or AGB intermediate gear assembly.

This AD also requires the removal of all

necessary engines on four engine

aircraft, and replacement with a

serviceable engine or replacement of the

AGB gearshaft cluster spur assembly, if

more than one affected engine is

installed on the aircraft. In addition, this

AD requires daily checks of the AGB/

TGB magnetic chip detector on CFM56–

3, –3B, and –3C series engines identified

in Table 1 of CFMI CFM56–3/–3B/–3C

SB No. 72–863, Revision 1, dated

November 18, 1997, or CFMI CFM56–3/

–3B/–3C SB No. 72–867, dated

November 28, 1997. If abnormal

magnetic particles are found, this AD

requires, prior to further flight,

installation of a serviceable AGB starter

gearshaft, TGB assembly, TGB input

bevel gear, or TGB output bevel gear.

This AD also requires, within 30 days

after the effective date of this AD,

installation of a serviceable AGB starter

gearshaft, serviceable TGB assembly,

serviceable TGB input bevel gear,

serviceable TGB output bevel gear,

serviceable AGB gearshaft cluster spur

assembly or an AGB intermediate gear

assembly, as applicable. Installation of a

serviceable AGB starter gearshaft, TGB

assembly, TGB input bevel gear or

output bevel gear, as applicable,

constitutes terminating action to the

daily AGB/TGB magnetic chip detector

inspections. The calendar end-date was

based upon FAA risk assessment and

parts availability. The actions are

required to be accomplished in

accordance with the service documents

described previously.

Since a situation exists that requires

the immediate adoption of this

regulation, it is found that notice and

opportunity for prior public comment

hereon are impracticable, and that good

cause exists for making this amendment

effective in less than 30 days.

Comments Invited

Although this action is in the form of

a final rule that involves requirements

affecting flight safety and, thus, was not

preceded by notice and an opportunity

for public comment, comments are

invited on this rule. Interested persons

are invited to comment on this 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

under the caption ADDRESSES. All

communications received on or before

the closing date for comments will be

considered, and this rule may be

amended in light of the comments

received. Factual information that

supports the commenter’s ideas and

suggestions is extremely helpful in

evaluating the effectiveness of the AD

action and determining whether

additional rulemaking action would be

needed.

Comments are specifically invited on

the overall regulatory, economic,

environmental, and energy aspects of

the rule that might suggest a need to

modify the 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 AD

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–ANE–54–AD.’’ The

postcard will be date stamped and

returned to the commenter.

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.

The FAA has determined that this

regulation is an emergency regulation

that must be issued immediately to

correct an unsafe condition in aircraft,

and is not a ‘‘significant regulatory

action’’ under Executive Order 12866. It

has been determined further that this

action involves an emergency regulation

under DOT Regulatory Policies and

Procedures (44 FR 11034, February 26,

1979). If it is determined that this

emergency regulation otherwise would

be significant under DOT Regulatory

Policies and Procedures, a final

regulatory evaluation will be prepared

and placed in the Rules Docket. A copy

of it, if filed, 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.

§ 39.13 [Amended]

2. Section 39.13 is amended by

adding the following new airworthiness

directive:

98–10–11 CFM International: Amendment

39–10523. Docket No. 97–ANE–54–AD.

Supersedes telegraphic AD T97–25–51.

Applicability: CFM International (CFMI)

CFM56–3, –3B, and –3C series turbofan

engines, having any of the engine serial

numbers (ESNs) identified in Table 1 of

CFMI CFM56–3/–3B/–3C Service Bulletin

(SB) No. 72–863, Revision 1, dated November

18, 1997, Table 1 of CFMI CFM56–3/–3B/–3C

SB No. 72–867, dated November 28, 1997, or

Table 1 of CFMI CFM56–3/–3B/–3C SB No.

72–873, Revision 1, dated February 5, 1998;

CFM56–5 series turbofan engines, having any

of the ESNs identified in Table 1 of CFMI

CFM56–5 SB No. 72–523, Revision 1, dated

January 30, 1998; CFM56–5B series turbofan

engines, having any of the ESNs identified in

Table 1 of CFMI CFM56–5B SB No. 72–211,

Revision 1, dated January 29, 1998; and

CFM56–5C series turbofan engines, having

any of the ESNs identified in Table 1 of CFMI

CFM56–5C SB No. 72–350, Revision 1, dated

January 30, 1998. These engines are installed

on but not limited to Boeing 737 series, and

Airbus Industrie A319, A320, A321, and

A340 series aircraft.

Note 1: This airworthiness directive (AD)

applies to each engine identified in the
27454 Federal Register / Vol. 63, No. 96 /Tuesday, May 19, 1998 /Rules and Regulations

preceding applicability provision, regardless

of whether it has been modified, altered, or

repaired in the area subject to the

requirements of this AD. For engines 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 (i)

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 inflight engine shutdowns due

to an accessory gearbox (AGB) starter

gearshaft, transfer gearbox (TGB) input bevel

gear, TGB output bevel gear, AGB gearshaft

cluster spur assembly or AGB intermediate

gear assembly failure, accomplish the

following:

(a) For twin engine aircraft that are

equipped with both engines identified by

ESN in Table 1 of the applicable SB noted

in the Applicability paragraph of this AD,

prior to further flight, accomplish the

following:

(1) Remove one of the engines, and replace

with an engine not identified by ESN in

Table 1 of the applicable SB noted in the

Applicability paragraph of this AD; or

(2) On one of the engines, accomplish the

following as applicable:

(i) For CFM56–3, –3B, and –3C series

engines:

(A) Replace the AGB starter gearshaft with

a serviceable part, as defined in paragraph (h)

of this AD, in accordance with CFMI CFM56–

3/–3B/–3C SB No. 72–863, Revision 1, dated

November 18, 1997,

(B) Replace the TGB assembly with a

serviceable part, as defined in paragraph (h)

of this AD, in accordance with CFMI CFM56–

3/–3B/–3C SB No. 72–865, dated November

18, 1997; or, replace the TGB input bevel gear

and/or output bevel gear, as applicable, with

a serviceable part in accordance with CFMI

CFM56–3/–3B/–3C SB No. 72–867, dated

November 28, 1997,

(C) Replace the AGB intermediate gear

assembly with a serviceable part, as defined

in paragraph (h) of this AD, in accordance

with CFMI CFM56–3/–3B/–3C SB No. 72–

873, Revision 1, dated February 5, 1998.

(ii) For CFM56–5 series engines, replace

the gearshaft cluster spur assembly with a

serviceable part, as defined in paragraph (h)

of this AD, in accordance with CFMI CFM56–

5 SB No. 72–523, Revision 1, dated January

30, 1998.

(iii) For CFM56–5B series engines, replace

the gearshaft cluster spur assembly with a

serviceable part, as defined in paragraph (h)

of this AD, in accordance with CFMI CFM56–

5B SB No. 72–211, Revision 1, dated January

29, 1998.

(b) For four engine aircraft that are

equipped with more than one engine

identified by ESN in Table 1 of CFMI

CFM56–5C SB No. 72–350, Revision 1,

dated January 30, 1998, prior to further

flight, accomplish the following:

(1) Remove at least all but one

affected engine from the aircraft, and

replace with serviceable engines not

identified by ESN in Table 1 of CFMI

CFM56–5C SB No. 72–350, Revision 1,

dated January 30, 1998; or

(2) Replace the gearshaft cluster spur

assembly with a serviceable part, as

defined in paragraph (h) of this AD, in

accordance with CFMI CFM56–5C SB

No. 72–350, Revision 1, dated January

30, 1998, on at least all but one affected

engine.

(c) For CFM56–3, –3B, and –3C series

engines identified by ESN in Table 1 of

CFMI CFM56–3/–3B/–3C SB No. 72–

863, Revision 1, dated November 18,

1997, or CFMI CFM56–3/–3B/–3C SB

No. 72–867, dated November 28, 1997,

prior to further flight, and thereafter

once per calendar day, perform checks

of the AGB/TGB magnetic chip detector

in accordance with CFMI CFM56–3/–

3B/–3C Alert Service Bulletin (ASB) No.

72–A861, Revision 3, dated December 3,

1997. If magnetic particles are found to

be abnormal in accordance with CFMI

CFM56–3/–3B/–3C ASB No. 72–A861,

Revision 3, dated December 3, 1997,

prior to further flight, accomplish the

following as applicable:

(1) For engines identified by ESN in

Table 1 of CFMI CFM56–3/–3B/–3C SB

No. 72–863, Revision 1, dated

November 18, 1997, remove the AGB

starter gearshaft, and replace with a

serviceable part, as defined in paragraph

(h) of this AD, in accordance with CFMI

CFM56–3/–3B/–3C SB No. 72–863,

Revision 1, dated November 18, 1997.

(2) For engines identified by ESN in

Table 1 of CFMI CFM56–3/–3B/–3C SB

No. 72–867, dated November 28, 1997,

remove the TGB assembly and replace

with a serviceable part, as defined in

paragraph (h) of this AD, in accordance

with CFMI CFM56–3/–3B/–3C SB No.

72–865, dated November 18, 1997; or,

remove the TGB input bevel gear and/

or TGB output bevel gear, as applicable,

and replace with serviceable parts, as

defined in paragraph (h) of this AD, in

accordance with CFMI CFM56–3/–3B/–

3C SB No. 72–867, dated November 28,

1997.

(d) For CFM56–3, –3B, and –3C series

engines identified by ESN in Table 1 of

CFMI CFM56–3/–3B/–3C SB No. 72–

863, Revision 1, dated November 18,

1997, remove the AGB starter gearshaft

within 30 days after the effective date of

this AD, and replace with a serviceable

part, as defined in paragraph (h) of this

AD, in accordance with CFMI CFM56–

3/–3B/–3C SB No. 72–863, Revision 1,

dated November 18, 1997. Installation of

a serviceable AGB starter gearshaft, as

defined in paragraph (h) of this AD, and

compliance with paragraph (e) of this

AD, if applicable, constitutes

terminating action to the daily AGB/

TGB magnetic chip detector checks

required by paragraph (c) of this AD.

(e) For CFM56–3, –3B, and –3C series

engines identified by ESN in Table 1 of

CFMI CFM56–3/–3B/–3C SB No. 72–

867, dated November 28, 1997, remove

the TGB assembly in accordance with

CFMI CFM56–3/–3B/–3C SB No. 72–

865, dated November 18, 1997; or,

remove the TGB input bevel gear and/

or output bevel gear, as applicable,

within 30 days after the effective date of

this AD, and replace with serviceable

parts, as defined in paragraph (h) of this

AD, in accordance with CFMI CFM56–

3/–3B/–3C SB No. 72–867, dated

November 28, 1997. Installation of a

serviceable TGB assembly, or TGB input

bevel gear and/or TGB output bevel

gear, as defined in paragraph (h) of this

AD, and compliance with paragraph (d)

of this AD if applicable, constitutes

terminating action to the daily AGB/

TGB magnetic chip detector checks

required by paragraph (c) of this AD.

(f) For CFM56–3, –3B, and –3C series

engines identified by ESN in Table 1 of

CFMI CFM56–3/–3B/–3C SB No. 72–

873, Revision 1, dated February 5, 1998,

remove the AGB intermediate gear

assembly within 30 days after the

effective date of this AD, and replace

with a serviceable part, as defined in

paragraph (h) of this AD, in accordance

with CFMI CFM56–3/–3B/–3C SB No.

72–873, Revision 1, dated February 5,

1998.

(g) For CFM56–5, –5B, and –5C series

engines identified by ESN in Table 1 of

CFMI CFM56–5 SB No. 72–523,

Revision 1, dated January 30, 1998,

CFMI CFM56–5B SB No. 72–211,

Revision 1, dated January 29, 1998, or

CFMI CFM56–5C SB No. 72–350,

Revision 1, dated January 30, 1998,

remove the gearshaft cluster spur

assembly within 30 days after the

effective date of this AD, and replace

with a serviceable part, as defined in

paragraph (h) of this AD, in accordance

with CFMI CFM56–5 SB No. 72–523,

Revision 1, dated January 30, 1998,

CFMI CFM56–5B SB No. 72–211,

Revision 1, dated January 29, 1998, or

CFMI CFM56–5C SB No. 72–350,

Revision 1, dated January 30, 1998, as

applicable.

(h) For the purposes of this AD, a

serviceable part is defined as an AGB

starter gearshaft, Part Number (P/N)

335–302–503–0, a TGB assembly, P/N

335–300–012–0, a TGB input bevel gear,

P/N 335–321–008–0, a TGB output

bevel gear, P/N 335–322–405–0, AGB

gearshaft cluster spur assembly, P/N

335–302–503–0, or an AGB intermediate

gear assembly, P/N 335–303–202–0, not
Federal Register / Vol. 63, No. 96 /Tuesday, May 19, 1998 /Rules and Regulations 27455

identified by part serial number in Table

1 of the applicable SB noted in the

Applicability Section of this AD.

(i) An alternative method of

compliance or adjustment of the initial

compliance time that provides an

acceptable level of safety may be used

if approved by the Manager, Engine

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, Engine Certification

Office.

Note 2: Information concerning the

existence of approved alternative methods of

compliance with this airworthiness directive,

if any, may be obtained from the Engine

Certification Office.

(j) The actions required by this AD shall be

accomplished in accordance with the

following CFMI service documents:

Document No. Page Revision Date

CFM56–3/–3B/–3C ASB No. 72–A861 ............................................................................... 1–10 ................. 3 ....................... Dec. 3, 1997.

Total Pages: 10

CFM56–3/–3B/–3C SB No. 72–863 .................................................................................... 1–39 ................. 1 ....................... Nov. 18, 1997.

Total Pages: 39

CFM56–3/–3B/–3C SB No. 72–865 .................................................................................... 1–8 ................... Original ............. Nov. 18, 1997.

Total Pages: 8

CFM56–3/–3B/–3C SB No. 72–867 .................................................................................... 1–11 ................. Original ............. Nov. 28, 1997.

Total Pages: 11

CFM56–3/–3B/–3C SB No. 72–873 .................................................................................... 1–21 ................. 1 ....................... Feb. 5, 1998.

Total Pages: 21

CFM56–5 SB No. 72–523 ................................................................................................... 1–33 ................. 1 ....................... Jan. 30, 1998.

Total Pages: 33

CFM56–5B SB No. 72–211 ................................................................................................ 1–28 ................. 1 ....................... Jan. 29, 1998.

Total Pages: 28

CFM56–5C SB No. 72–350 ................................................................................................ 1–28 ................. 1 ....................... Jan. 30, 1998.

Total Pages: 28

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 CFM International, Technical

Publications Department, 1 Neumann Way,

Cincinnati, OH 45215; telephone (513) 552–

2981, fax (513) 552–2816. Copies may be

inspected at the FAA, New England Region,

Office of the Regional Counsel, 12 New

England Executive Park, Burlington, MA; or

at the Office of the Federal Register, 800

North Capitol Street, NW., suite 700,

Washington, DC.

(k) This amendment supersedes telegraphic

AD T97–25–51, issued December 4, 1997.

(l) This amendment becomes effective on

June 3, 1998.

Issued in Burlington, Massachusetts, on

May 7, 1998.

Thomas A. Boudreau,

Acting Manager, Engine and Propeller

Directorate, Aircraft Certification Service.

[FR Doc. 98–12916 Filed 5–18–98; 8:45 am]

BILLING CODE 4910–13–U

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 96–NM–263–AD; Amendment

39–10530; AD 98–11–03]

RIN 2120–AA64

Airworthiness Directives; Boeing

Model 727 Series Airplanes

AGENCY: Federal Aviation

Administration, DOT.

ACTION: Final rule.

SUMMARY: This amendment supersedes

an existing airworthiness directive (AD),

applicable to certain Boeing Model 727

series airplanes, that currently requires

that the FAA-approved maintenance

inspection program be revised to

include inspections that will give no

less than the required damage tolerance

rating for each Structural Significant

Item, and repair of cracked structure.

That AD was prompted by a structural

re-evaluation by the manufacturer that

identified additional structural elements

where, if damage were to occur,

supplemental inspections may be

required for timely detection. This

amendment requires additional and

expanded inspections, and repair of

cracked structure. This amendment also

expands the applicability of the existing

AD to include additional airplanes. The

actions specified by this AD are

intended to ensure the continued

structural integrity of the entire Boeing

Model 727 fleet.

DATES: Effective June 23, 1998.

The incorporation by reference of

certain publications listed in the

regulations is approved by the Director

of the Federal Register as of June 23,

1998.

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:

Walter Sippel, Aerospace Engineer,

Airframe Branch, ANM–120S, FAA,

Seattle Aircraft Certification Office,

1601 Lind Avenue, SW., Washington;

telephone (425) 227–2774; fax (425)

227–1181.

SUPPLEMENTARY INFORMATION: A

proposal to amend part 39 of the Federal

Aviation Regulations (14 CFR part 39)

by superseding airworthiness directive

(AD) 84–21–05, amendment 39–4920

(49 FR 38931, October 2, 1984), which

is applicable to all Boeing Model 727

series airplanes, was published in the

Federal Register on May 29, 1997 (62

FR 29081). That action proposed to

supersede AD 84–21–05 to continue to

require that the FAA-approved

maintenance program be revised to

include inspections that will give no

less than the required damage tolerance