46186 Federal Register / Vol. 62, No. 169 / Tuesday, September 2, 1997 / Rules and Regulations

correct an unsafe condition in aircraft,

and that it 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:

97–18–08 British Aerospace Regional

Aircraft [Formerly Jetstream Aircraft

Limited, British Aerospace (Commercial

Aircraft) Limited]: Amendment 39–

10118. Docket 97–NM–181–AD.

Applicability: Jetstream Model 4101

airplanes, constructors numbers 41004

through 41100 inclusive, 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 reduced structural integrity and

potential collapse of the main landing gear

(MLG) due to loose spherical bearings of the

drag brace, accomplish the following:

(a) For all airplanes: Within 30 days after

the effective date of this AD, perform a visual

inspection to detect wear damage of the drag

brace of the left- and right-hand MLG, in

accordance with Jetstream Alert Service

Bulletin J41–A32–061, dated July 11, 1997.

(1) For airplanes on which no wear damage

has been detected and that have accumulated

8,000 or more total landings as of the

effective date of this AD or on which APPH

Service Bulletin AIR84352–32–05 has been

accomplished: Prior to further flight, perform

an inspection to detect movement of the

spherical bearing of the drag brace and

measure the area between the lower link and

the strut, in accordance with the Jetstream

alert service bulletin.

(i) If no movement of the spherical bearing

is detected and the measurement of the area

between the lower link and the strut is

within the limits specified by the service

bulletin, no further action is required by this

AD.

Note 2: For the purposes of this AD, ‘‘flight

day’’ is defined as any day on which the

airplane is flown.

(ii) If any movement is detected or the

measurement of the area between the lower

link and the strut is beyond the limits

specified by the service bulletin, repeat the

inspections required by paragraph (a) of this

AD prior to the first flight of the day for the

next 100 flight days of the airplane.

(2) For all other airplanes on which no

wear damage has been detected: Prior to

further flight, perform an inspection to detect

movement of the spherical bearing of the

drag brace and measure the area between the

lower link and the strut, in accordance with

the service bulletin.

(i) If no movement of the spherical bearing

is detected, and the measurement of the area

between the lower link and the strut is

within the limits specified by the service

bulletin, repeat the inspections required by

paragraph (a) of this AD at the time specified

in paragraph (a)(2)(i)(A) or (a)(2)(i)(B) of this

AD, as applicable.

(A) For drag braces that have accumulated

less than 501 total landings: Repeat the

inspections at intervals not to exceed 100

flights until the drag brace has accumulated

500 total landings.

(B) For drag braces that have accumulated

more than 500 total landings, but less than

8,000 total landings: Repeat the inspections

at intervals not to exceed 1,000 flights.

(ii) If any movement is detected or the

measurement of the area between the lower

link and the strut is beyond the limits

specified by the service bulletin, repeat the

inspections required by paragraph (a) of this

AD prior to the first flight of the day for the

next 100 flight days of the airplane.

(b) For all airplanes: If any wear damage of

the drag brace is detected during any

inspections required by this AD, prior to

further flight, remove the wear damaged

part(s) and replace with a new or serviceable

part, in accordance with Jetstream Alert

Service Bulletin J41–A32–061, dated July 11,

1997. Within 30 days after the replacement

of a wear damaged part with a new or

serviceable part, perform the requirements of

paragraph (a) of this AD.

(c) Accomplishment of APPH Service

Bulletin AIR84352–32–05, dated June 1997,

constitutes terminating action for the

repetitive inspection requirements of

paragraph (a)(2) of this AD.

(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,

Standardization Branch, ANM–113.

Operators shall submit their requests through

an appropriate FAA Principal Maintenance

Inspector, who may add comments and then

send it to the Manager, Standardization

Branch, ANM–113.

Note 3: Information concerning the

existence of approved alternative methods of

compliance with this AD, if any, may be

obtained from the Standardization Branch,

ANM–113.

(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 actions shall be done in accordance

with Jetstream Alert Service Bulletin J41–

A32–061, dated July 11, 1997. 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 AI(R)

American Support, Inc., 13850 Mclearen

Road, Herndon, Virginia 20171. 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

September 17, 1997.

Issued in Renton, Washington, on August

25, 1997.

Gary L. Killion,

Acting Manager, Transport Airplane

Directorate, Aircraft Certification Service.

[FR Doc. 97–23065 Filed 8–29–97; 8:45 am]

BILLING CODE 4910–13–P

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 97–NM–130–AD; Amendment

39–10115; AD 97–18–05]

RIN 2120–AA64

Airworthiness Directives; Boeing

Model 757 Series Airplanes Equipped

With Pratt & Whitney Engines

AGENCY: Federal Aviation

Administration, DOT.

ACTION: Final rule; request for

comments.

SUMMARY: This amendment supersedes

an existing airworthiness directive (AD),

applicable to certain Boeing Model 757
Federal Register / Vol. 62, No. 169 / Tuesday, September 2, 1997 / Rules and Regulations 46187

series airplanes, that currently requires

repetitive inspections to detect cracking

in the midspar fuse pins; replacement

with new or refinished fuse pins, if

necessary; and repetitive inspections of

newly installed fuse pins. This AD

requires earlier initial inspections and

replacements; more frequent repetitive

inspections of certain fuse pins; and

replacement with new fuse pins, if

necessary. This amendment is prompted

by reports of fatigue cracking of the

midspar fuse pins and by fatigue test

data indicating that current inspection

thresholds and intervals for repetitive

inspections are inadequate to detect

fatigue cracking in a timely manner. The

actions specified in this AD are

intended to detect and correct such

fatigue cracking, which could lead to

separation of the strut and engine from

the wing of the airplane.

DATES: Effective September 17, 1997.

The incorporation by reference of

Boeing Alert Service Bulletin 757–

54A0019, Revision 6, dated July 18,

1997, as listed in the regulations, is

approved by the Director of the Federal

Register as of September 17, 1997.

The incorporation by reference of

Boeing Service Bulletin 757–54A0019,

Revision 5, dated March 17, 1994, as

listed in the regulations, was approved

previously by the Director of the Federal

Register as of April 10, 1996 (61 FR

9599, March 11, 1996).

Comments for inclusion in the Rules

Docket must be received on or before

November 3, 1997.

ADDRESSES: Submit comments in

triplicate to the Federal Aviation

Administration (FAA), Transport

Airplane Directorate, ANM–103,

Attention: Rules Docket No. 97-NM–

130-AD, 1601 Lind Avenue, SW.,

Renton, Washington 98055–4056.

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:

Todd Martin, Aerospace Engineer,

Airframe Branch, ANM–120S, FAA,

Transport Airplane Directorate, Seattle

Aircraft Certification Office, 1601 Lind

Avenue, SW., Renton, Washington;

telephone (425) 227–2781; fax (425)

227–1181.

SUPPLEMENTARY INFORMATION: On March

1, 1996, the FAA issued AD 96–05–07,

amendment 39–9533 (61 FR 9599,

March 11, 1996), applicable to certain

Boeing Model 757 series airplanes. That

AD requires repetitive inspections to

detect cracking in the midspar fuse pins,

regardless of whether they are straight,

bulkhead, or 15–5PH fuse pins, and

replacement of discrepant pins with

new straight fuse pins, refinished

straight fuse pins, or new corrosionresistant steel (15–5PH) fuse pins,

depending on the type of cracked pin.

The actions required by that AD are

intended to prevent cracking of the

midspar fuse pins, which may lead to

separation of the strut and engine from

the wing of the airplane.

Actions Since Issuance of Previous Rule

Since the issuance of AD 96–05–07,

the FAA has received two reports

indicating the detection of damaged

straight fuse pins (one broken pin and

one cracked pin) on Model 757 series

airplanes equipped with Pratt &

Whitney engines. In these instances,

damage to the fuse pins was detected

before reaching the threshold specified

in AD 96–05–07 for conducting an

initial inspection of the fuse pins. In

addition, since the issuance of that AD,

the FAA was informed by Boeing that

refinished straight fuse pins have a

shorter fatigue life than new straight

fuse pins.

Based on data from fatigue testing by

the manufacturer and reports of early

cracking, the FAA finds that the current

inspection thresholds and intervals for

repetitive inspections are inadequate to

detect cracking in a timely manner.

Consequently, it is necessary to lower

the threshold for the initial inspection

and conduct repetitive inspections of

these fuse pins more frequently than

currently required by AD 96–05–07. In

addition, the FAA has determined that

the action specified in paragraph

(b)(2)(i) of AD 96–05–07, which requires

the replacement of cracked refinished

straight fuse pins with crack-free

refinished straight fuse pins, is no

longer acceptable. The FAA concludes

that, because of the safety implications

and consequences associated with the

fatigue cracking of fuse pins, the

replacement of refinished straight fuse

pins must be made with either new

straight fuse pins or new 15–5PH fuse

pins. However, the FAA has determined

that the existing refinished straight fuse

pins, which are already installed on

Boeing Model 757 series airplanes and

do not have cracks, may continue in use

in accordance with the requirements of

this AD.

The FAA is considering a separate

rulemaking action to address the same

unsafe condition on certain Model 757

airplanes equipped with Rolls Royce

engines.

Explanation of Relevant Service

Information

Since the issuance of AD 96–05–07,

the FAA has reviewed and approved

Boeing Alert Service Bulletin 757–

54A0019, Revision 6, dated July 18,

1997, which continues specifications

similar to those in Boeing Service

Bulletin 757–54A0019, Revision 5,

dated March 17, 1994 (which was

referenced in AD 96–05–07 as the

appropriate source of service

information). The relevant changes in

Revision 6 are procedures for earlier

initial inspections and replacements;

more frequent repetitive inspections of

certain fuse pins; and replacement with

new fuse pins, if necessary. In addition,

Revision 6 specifies the replacement of

cracked refinished straight fuse pins

with new straight fuse pins or 15–5PH

fuse pins.

Explanation of Requirements of Rule

Since an unsafe condition has been

identified that is likely to exist or

develop on other airplanes of this same

type design, this AD supersedes AD 96–

05–07 to continue to require repetitive

inspections to detect cracking in the

midspar fuse pins; replacement with

new or refinished fuse pins, if

necessary; and repetitive inspections of

newly installed fuse pins. This AD

requires earlier initial inspections and

replacements; more frequent repetitive

inspections of certain fuse pins; and

replacement with new fuse pins, if

necessary. This AD also requires the

replacement of cracked refinished

straight fuse pins with new straight fuse

pins or 15–5PH fuse pins. These actions

are required to be accomplished in

accordance with Revision 6 of the alert

service bulletin described previously.

Differences Between the AD and the

Relevant Service Bulletin

Operators should note that, although

Boeing Alert Service Bulletin 757–

54A0019, Revision 6, dated July 18,

1997, specifies that a cracked bulkhead

fuse pin may be replaced with either a

new straight fuse pin or a new 15–5PH

fuse pin, this AD requires a bulkhead

fuse pin to be replaced only with a new

15–5PH fuse pin. The FAA has

determined that because 15–5PH fuse

pins are made from corrosion-resistant

steel, 15–5PH fuse pins are less likely to

be subject to fatigue cracking and stress

corrosion cracking, and, as a result, have

a longer service life than straight fuse

pins or bulkhead fuse pins. The FAA

also considers that this action is

necessary to support the continued

airworthiness of Boeing Model 757
46188 Federal Register / Vol. 62, No. 169 / Tuesday, September 2, 1997 / Rules and Regulations

series airplanes equipped with Pratt &

Whitney engines.

Operators also should note that

Revision 6 of the previously described

alert service bulletin specifies the

replacement of bulkhead fuse pins

within 6,000 total flight cycles on the

bulkhead fuse pins. However, this AD

requires the replacement of bulkhead

fuse pins within 3,000 flight cycles on

the bulkhead fuse pins after April 10,

1996, the effective date of AD 96–05–07.

The FAA has determined that

continuing the requirement for such

replacement, which was required in AD

96–05–07, is sufficient to detect and

correct the initiation and propagation of

fatigue cracking in the midspar fuse

pins.

In addition, operators should note

that the applicability of this AD differs

from the effectivity listing in Revision 6

of the previously referenced alert

service bulletin. The FAA has

determined that to adequately address

the problem of fatigue cracking in the

midspar fuse pins, this AD should

include Model 757 series airplanes (all

serial numbers) equipped with Pratt &

Whitney engines, as previously

specified in AD 96–05–07.

Interim Action

This is considered to be interim

action until final action is identified, at

which time the FAA may consider

further rulemaking.

Determination of Rule’s Effective Date

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 fewer 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 shall 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 rule must

submit a self-addressed, stamped

postcard on which the following

statement is made: ‘‘Comments to

Docket Number 97–NM–130–AD.’’ The

postcard will be date stamped and

returned to the commenter.

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.

The FAA has determined that this

regulation is an emergency regulation

that must be issued immediately to

correct an unsafe condition in aircraft,

and that it 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

removing amendment 39–9533 (61 FR

9599, March 11, 1996), and by adding a

new airworthiness directive (AD),

amendment 39–10115, to read as

follows:

97–18–05 Boeing: Amendment 39–10115.

Docket 97–NM–130–AD. Supersedes AD

96–05–07, Amendment 39–9533.

Applicability: Model 757 series airplanes

equipped with Pratt & Whitney engines,

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 (f) 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.

Note 2: Inspections accomplished prior to

the effective date of this amendment in

accordance with the procedures described in

Boeing Service Bulletin 757–54A0019,

Revision 5, dated March 17, 1994; Revision

4, dated May 27, 1993; Revision 3, dated

March 26, 1992; or Revision 2, dated October

11, 1989; are considered acceptable for

compliance with the applicable inspections

specified in this amendment.

To detect and correct fatigue cracking of

the midspar fuse pins, which could lead to

separation of the strut and engine from the

wing of the airplane, accomplish the

following:

(a) For airplanes equipped with straight

fuse pins, part number (P/N) 311N5067–1:

Prior to the accumulation of 1,000 total flight

cycles on the straight fuse pin, or within 60

days after the effective date of this AD,

whichever occurs later, perform an eddy

current inspection to detect fatigue cracking

in the fuse pin, in accordance with Boeing

Alert Service Bulletin 757–54A0019,

Revision 6, dated July 18, 1997.

(1) If no cracking is detected, repeat the

inspection thereafter at intervals not to

exceed 500 flight cycles on the straight fuse

pin.

(2) If any cracking is detected, prior to

further flight, accomplish the requirements of
Federal Register / Vol. 62, No. 169 / Tuesday, September 2, 1997 / Rules and Regulations 46189

either paragraph (a)(2)(i) or (a)(2)(ii) of this

AD.

(i) Replace the cracked straight fuse pin

with a new straight fuse pin, P/N 311N5067–

1, and prior to the accumulation of 1,000

total flight cycles on the newly installed

straight fuse pin, perform an eddy current

inspection to detect fatigue cracking in the

fuse pin, in accordance with the alert service

bulletin. Repeat the inspection thereafter at

intervals not to exceed 500 flight cycles on

the newly installed straight fuse pin. Or

(ii) Replace the cracked straight fuse pin

with a new 15–5PH fuse pin, P/N 311N5217–

1, and prior to the accumulation of 14,000

total flight cycles on the newly installed 15–

5PH fuse pin, perform an eddy current

inspection to detect fatigue cracking in the

fuse pin, in accordance with the procedures

described in the alert service bulletin. Repeat

the inspection thereafter at intervals not to

exceed 3,500 flight cycles on the newly

installed 15–5PH fuse pin.

(b) For airplanes equipped with refinished

straight fuse pins, P/N 311N5067–1: Prior to

the accumulation of 500 total flight cycles on

the refinished straight fuse pin, or within 60

days after the effective date of this AD,

whichever occurs later, perform an eddy

current inspection to detect fatigue cracking

in the fuse pin, in accordance with Boeing

Alert Service Bulletin 757–54A0019,

Revision 6, dated July 18, 1997.

(1) If no cracking is detected, repeat the

inspection thereafter at intervals not to

exceed 500 flight cycles on the refinished

straight fuse pin.

(2) If any cracking is detected, prior to

further flight, accomplish the requirements of

either paragraph (b)(2)(i) or (b)(2)(ii) of this

AD.

(i) Replace the cracked fuse pin with a new

straight fuse pin, P/N 311N5067–1, and prior

to the accumulation of 1,000 total flight

cycles on the newly installed straight fuse

pin, perform an eddy current inspection to

detect fatigue cracking in the new straight

fuse pin, in accordance with the procedures

described in the alert service bulletin. Repeat

this inspection thereafter at intervals not to

exceed 500 flight cycles on the newly

installed straight fuse pin. Or

(ii) Replace the cracked fuse pin with a

new 15–5PH fuse pin, P/N 311N5217–1, and

prior to the accumulation of 14,000 total

flight cycles on the newly installed 15–5PH

fuse pin, perform an eddy current inspection

to detect fatigue cracking in the fuse pin, in

accordance with the procedures described in

the alert service bulletin. Repeat the

inspection thereafter at intervals not to

exceed 3,500 flight cycles on the newly

installed 15–5PH fuse pin.

(c) For airplanes equipped with bulkhead

fuse pins, P/N 311N5211–1: Within 3,000

flight cycles on the bulkhead fuse pins after

April 10, 1996 (the effective date of AD 96–

05–07, amendment 39–9533), replace the

bulkhead fuse pin with a new 15–5PH fuse

pin, P/N 311N5217–1, in accordance with

Boeing Service Bulletin 757–54A0019,

Revision 5, dated March 17, 1994, or Boeing

Alert Service Bulletin 757–54A0019,

Revision 6, dated July 18, 1997, and

accomplish the requirements of paragraph (d)

of this AD.

(d) For airplanes equipped with 15–5PH

fuse pins: Prior to the accumulation of 14,000

total flight cycles on the 15–5PH fuse pin,

perform an eddy current inspection to detect

fatigue cracking in those fuse pins, in

accordance with the procedures described in

Boeing Alert Service Bulletin 757–54A0019,

Revision 6, dated July 18, 1997.

(1) If no cracking is detected, repeat the

inspection thereafter at intervals not to

exceed 3,500 flight cycles on the 15–5PH fuse

pin.

(2) If any cracking is detected, prior to

further flight, replace the cracked 15–5PH

fuse pin with a new 15–5PH fuse pin, P/N

311N5217–1, and prior to the accumulation

of 14,000 total flight cycles on the newly

installed 15–5PH fuse pin, perform an eddy

current inspection to detect fatigue cracking

in the newly installed 15–5PH fuse pin; in

accordance with the procedures described in

the alert service bulletin. Repeat this

inspection thereafter at intervals not to

exceed 3,500 flight cycles on the newly

installed 15–5PH fuse pin.

(e) Fuse pins must be of the same type on

the same strut. For example, a steel fuse pin

having P/N 311N5067–1 may not be installed

on the same strut that has a 15–5PH fuse pin

having P/N 311N5217–1 installed on that

strut. However, fuse pins on one strut may

differ from those on another strut, provided

the fuse pins are not of mixed types on the

same strut.

(f) 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 3: Information concerning the

existence of approved alternative methods of

compliance with this AD, if any, may be

obtained from the Seattle ACO.

(g) 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.

(h) The inspections and replacements shall

be done in accordance with Boeing Service

Bulletin 757–54A0019, Revision 5, dated

March 17, 1994, or Boeing Alert Service

Bulletin 757–54A0019, Revision 6, dated July

18, 1997.

(1) The incorporation by reference of

Boeing Alert Service Bulletin 757–54A0019,

Revision 6, dated July 18, 1997, was

approved by the Director of the Federal

Register in accordance with 5 U.S.C. 552(a)

and 1 CFR part 51.

(2) The incorporation by reference of

Boeing Service Bulletin 757–54A0019,

Revision 5, dated March 17, 1994, was

approved previously by the Director of the

Federal Register in accordance with 5 U.S.C.

552(a) and 1 CFR part 51 as of April 10, 1996

(61 FR 9599, March 11, 1996).

(3) 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.

(i) This amendment becomes effective on

September 17, 1997.

Issued in Renton, Washington, on August

21, 1997.

Darrell M. Pederson,

Acting Manager, Transport Airplane

Directorate, Aircraft Certification Service.

[FR Doc. 97–23176 Filed 8–29–97; 8:45 am]

BILLING CODE 4910–13–U

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 97–NM–125–AD; Amendment

39–10114; AD 97–18–04]

RIN 2120–AA64

Airworthiness Directives; Boeing

Model 757 Series Airplanes Equipped

With Rolls Royce Engines

AGENCY: Federal Aviation

Administration, DOT.

ACTION: Final rule; request for

comments.

SUMMARY: This amendment supersedes

an existing airworthiness directive (AD),

applicable to certain Boeing Model 757

series airplanes, that currently requires

repetitive inspections to detect fatigue

cracking in the midspar fuse pins;

replacement with new or refinished fuse

pins, if necessary; and repetitive

inspections of newly installed fuse pins.

This AD requires earlier initial

inspections and replacements; more

frequent repetitive inspections of certain

fuse pins; and replacement with new

fuse pins, if necessary. This amendment

is prompted by reports of fatigue

cracking of the midspar fuse pins and by

fatigue test data indicating that current

inspection thresholds and intervals for

repetitive inspections are inadequate to

detect fatigue cracking in a timely

manner. The actions specified in this

AD are intended to detect and correct

such fatigue cracking, which could lead

to separation of the strut and engine

from the wing of the airplane.

DATES: Effective September 17, 1997.

The incorporation by reference of

Boeing Alert Service Bulletin 757–

54A0020, Revision 6, dated July 18,

1997, as listed in the regulations, is

approved by the Director of the Federal

Register as of Sepember 17, 1997.

The incorporation by reference of

Boeing Service Bulletin 757–54A0020,

Revision 5, dated March 17, 1994, as