Federal Register / Vol. 62, No. 77 / Tuesday, April 22, 1997 / Rules and Regulations 19477

ticketless carrier. The statistics do not

indicate how many of the remaining

complaints may have involved ticketless

transactions, but of the 36 overcharge

complaints against Major U.S. carriers

(i.e., airlines with revenues over $1

billion per year), only three were against

Southwest Airlines or United Airlines,

two Major carriers with the earliest

electronic ticketing programs.

We have no rules that require

reservation or fare information to appear

on conventional tickets, and we will not

require this information to be furnished

in writing to ticketless passengers at this

time. As far as we are aware, all airlines

that offer electronic ticketing provide a

paper itinerary showing the fare and

reservation status either automatically

or upon request. With most carriers,

passengers also have the option of a

conventional paper ticket if they prefer.

A large percentage of ticketless

transactions are paid for by credit card,

and those passengers have the disputeresolution procedures of the Fair Credit

Billing Act available to them in the

event of a problem. Nonetheless, we

will continue to monitor complaints in

these areas and will not hesitate to take

further action in the future if it is

warranted.

Likewise, the Department will

continue to monitor the evolution of

ticketless travel and any consumer

problems that may arise from the

practice. The compliance policy stated

herein will be reconsidered if

circumstances so justify. However,

before making any substantive change in

the policy, we will provide public

notice of our planned actions.

We note that under present rules,

certificated carriers must maintain

consumer complaint records for a

period of three years, flight coupons

from tickets for a period of one year, and

other records related to errors, oversales,

irregularities, and delays in handling of

passengers for a period of one year. (14

CFR 249.20.) While we see no need at

this time to impose additional

recordkeeping requirements on carriers

using electronic ticketing systems, we

encourage all carriers to maintain

records sufficient and in such a fashion

as to help the Department make

informed decisions in the future in this

important and evolving area of air

transportation.

The compliance policy set forth above

is an attempt to provide carriers the

maximum flexibility to develop their

ticketless travel systems while at the

same time providing a measure of

protection to consumers from unfair or

deceptive practices prohibited by 49

U.S.C. 41712. At the same time,

however, carriers may find it

advantageous to continue to provide the

written DOT ticket notices to ticketless

passengers in advance or to consider

implementing the innovative

notification systems discussed in the

comments submitted in this docket

(some of which are summarized above).

In this regard, carriers may ultimately

decide that it is in their overall best

financial interest to do so considering

that the preemption protections of 49

U.S.C. 41713 and 14 CFR 253.1 may not

apply unless notice of contract of

carriage terms is provided to ticketless

passengers at the time of sale either

orally or by contemporaneously mailed

(or faxed, emailed, etc.) written notice.

The policy described here does not

affect the existing notice requirements

for conventional paper tickets. Those

tickets must continue to be

accompanied by the written notices

described in DOT regulations.

Accordingly, it shall be the

compliance policy of the Department

that ticket notices required by

Department regulations shall be given or

made readily available to electronically

ticketed passengers in writing in a

manner such as described above no later

than the time that they check in for the

first flight in their itinerary.

Issued this 8th day of April, 1997 at

Washington, D.C.

Charles A. Hunnicutt,

Assistant Secretary for Aviation and

International Affairs.

[FR Doc. 97–10147 Filed 4–21–97; 8:45 am]

BILLING CODE 4910–62–P

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 97–NM–61–AD; Amendment

39–9995; AD 97–08–07]

RIN 2120–AA64

Airworthiness Directives; McDonnell

Douglas Model DC–9–80 Series

Airplanes and Model MD–88 Airplanes

AGENCY: Federal Aviation

Administration, DOT.

ACTION: Final rule; request for

comments.

SUMMARY: This amendment supersedes

an existing airworthiness directive (AD),

applicable to certain McDonnell

Douglas Model DC–9–80 series

airplanes and Model MD–88 airplanes,

that currently requires an inspection to

determine the type of fluorescent light

ballasts installed in the cabin sidewall;

and installation of a protective cover on

the ballast, replacement, or removal/

disconnection of the ballast, if

necessary. That action also requires, for

some airplanes, removal of the dust

barriers from the outboard ceiling

panels, and installation of modified

outboard ceiling panels. This

amendment would add a requirement to

replace certain ballasts on which a

protective cover is installed with other

ballasts, or removal/disconnection of

the ballast. This amendment is

prompted by additional reports of heavy

smoke and fumes emitting from the

ceiling panels in the forward passenger

cabin due to the failure of the

fluorescent light ballasts. The actions

specified in this AD are intended to

prevent a fire in the passenger

compartment, which could result from

failure of the fluorescent light ballast of

the upper and lower cabin sidewall, and

consequent failure of the dust barriers of

the outboard ceiling panel.

DATES: Effective May 7, 1997.

The incorporation by reference of

McDonnell Douglas Alert Service

Bulletin MD80–33A110, dated February

25, 1997, and McDonnell Douglas Alert

Service Bulletin MD80–33A110,

Revision 1, dated March 11, 1997, as

listed in the regulations, is approved by

the Director of the Federal Register as of

May 7, 1997.

The incorporation by reference of

certain other publications, as listed in

the regulations, was approved

previously by the Director of the Federal

Register as of June 17, 1996 (61 FR

27251, May 31, 1996).

Comments for inclusion in the Rules

Docket must be received on or before

June 23, 1997.

ADDRESSES: Submit comments in

triplicate to the Federal Aviation

Administration (FAA), Transport

Airplane Directorate, ANM–103,

Attention: Rules Docket No. 97–NM–

61–AD, 1601 Lind Avenue, SW.,

Renton, Washington 98055–4056.

The service information referenced in

this AD may be obtained from

McDonnell Douglas Corporation, 3855

Lakewood Boulevard, Long Beach,

California 90846, Attention: Technical

Publications Business Administration,

Department C1–L51 (2–60). This

information may be examined at the

FAA, Transport Airplane Directorate,

1601 Lind Avenue, SW., Renton,

Washington; or at the FAA, Transport

Airplane Directorate, Los Angeles

Aircraft Certification Office, 3960

Paramount Boulevard, Lakewood,

California; or at the Office of the Federal

Register, 800 North Capitol Street, NW.,

suite 700, Washington, DC.
19478 Federal Register / Vol. 62, No. 77 / Tuesday, April 22, 1997 / Rules and Regulations

FOR FURTHER INFORMATION CONTACT: J.

Kirk Baker, Aerospace Engineer,

Systems and Equipment Branch, ANM–

130L, FAA, Los Angeles Aircraft

Certification Office, 3960 Paramount

Boulevard, Lakewood, California 90712;

telephone (310) 627–5345; fax (310)

627–5210.

SUPPLEMENTARY INFORMATION: On May

22, 1996, the FAA issued AD 96–11–13,

amendment 39–9638 (61 FR 27251, May

31, 1996), applicable to certain

McDonnell Douglas Model DC–9–80

series airplanes and Model MD–88

airplanes. That AD currently requires a

one-time visual inspection to determine

the type of fluorescent light ballasts

installed in the cabin sidewall; and

installation of a protective cover on the

ballast, replacement, or removal/

disconnection of the ballast, if

necessary. That AD also requires, for

some airplanes, removal of dust barriers

from the outboard ceiling panels, and

installation of modified outboard ceiling

panels. That action was prompted by

reports of smoke, fumes, and/or

electrical fire emitting from the baggage

bin of the aft passenger compartment

and from the dust barriers of the

outboard ceiling due to the failure of the

fluorescent light ballasts. The actions

required by that AD are intended to

prevent a fire in the passenger

compartment, which could result from

failure of the fluorescent light ballast of

the upper and lower cabin sidewall, and

consequent failure of the dust barriers of

the outboard ceiling panel.

Actions Since Issuance of Previous Rule

Since the issuance of that AD, the

FAA has received two reports of heavy

smoke and fumes emitting from the

ceiling panels in the forward passenger

cabin on McDonnell Douglas Model

DC–9–80 series airplanes. Investigation

revealed that the most recent incident

occurred following accomplishment of

the installation of a protective cover on

a certain Day-Ray Products Incorporated

ballast, as required by AD 96–11–13.

This ballast failed and consequently

caused electrical arcing that penetrated

the protective cover, which resulted in

a fire that damaged the upper insulation

blanket and outboard ceiling panel at

station 1022. At this time, the FAA is

unaware if such an installation has been

accomplished on the Model DC–9–80

series airplane involved in the other

incident.

The FAA has determined that

installation of a protective cover on

certain Day-Ray Products Incorporated

ballasts, as required by AD 96–11–13,

does not adequately preclude failure of

such fluorescent light ballasts of the

upper and lower cabin sidewall, which

could result in a fire in the passenger

compartment.

Explanation of Relevant Service

Information

Additionally, since issuance of AD

96–11–13, the FAA has reviewed and

approved McDonnell Douglas Alert

Service Bulletin MD80–33A110, dated

February 25, 1997, and McDonnell

Douglas Alert Service Bulletin MD80–

33A110, Revision 1, dated March 11,

1997. These alert service bulletins

supersede (but do not cancel) the

procedures identified in McDonnell

Douglas Alert Service Bulletin MD80–

33A107, dated April 25, 1996 (which is

referenced in AD 96–11–13 as the

appropriate source of service

information). The procedures in these

new alert service bulletins are

essentially identical to the procedures

in Alert Service Bulletin MD80–33A107;

however, the procedures for installation

of a protective cover have not been

retained in the new alert service

bulletins.

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–

11–13 to continue to require a one-time

visual inspection to determine the type

of fluorescent light ballasts installed in

the cabin sidewall; and replacement, or

removal/disconnection of the ballast, if

necessary. This AD also continues to

require, for some airplanes, removal of

dust barriers from the outboard ceiling

panels, and installation of modified

outboard ceiling panels. This AD would

add a requirement to replace the

currently installed Day-Ray Products

Incorporated ballasts, on which a

protective cover is installed, with a

Bruce Industries Incorporated ballast.

All actions except the removal/

disconnection would be required to be

accomplished in accordance with alert

service bulletins described previously.

Operators should note that, in

addition to the recommendations of the

alert service bulletins described

previously, this AD provides the

following two additional options for

airplanes on which any Day-Ray

Products Incorporated ballast that has a

protective cover is installed:

1. Replacement of the Day-Ray

Products Incorporated ballast and

protective cover with an FAA-approved

solid state electronic light ballast

system, in accordance with an

applicable Supplemental Type

Certificate (STC) or other method

approved by the FAA. Or

2. Removal or electrical disconnection

of the ballast, stowage of the ballast, and

protection of the loose wiring.

The FAA finds that accomplishment

of these actions will address the

identified unsafe condition for the

affected airplanes.

Operators should also note that the

applicability of the proposal differs from

the applicability of AD 96–11–13 in the

following two respects:

1. The applicability of this AD

references two new alert service

bulletins that are not referenced in the

applicability statement of AD 96–11–13:

McDonnell Douglas Alert Service

Bulletin MD80–33A110, dated February

25, 1997, and Revision 1, dated March

11, 1997. The applicability of AD 96–

11–13 references: McDonnell Douglas

Alert Service Bulletin MD80–33A107,

dated April 25, 1996, and McDonnell

Douglas Alert Service Bulletin MD80–

25A353, dated March 14, 1996. The

FAA finds that the effectivity listing of

either of the two new alert service

bulletins includes the same airplanes as

those listed in the effectivity listings of

McDonnell Douglas Alert Service

Bulletins MD80–33A107 and MD80–

25A353 combined.

2. The applicability statement of this

AD also includes the phase, ‘‘excluding

airplanes equipped with solid state

electronic light ballasts.’’ (The

applicability statement of AD 96–11–13

does not include this phrase.) The FAA

finds that operators could misinterpret

the applicability statement of AD 96–

11–13, as currently worded, to indicate

that airplanes equipped with these

ballasts are subject to the requirements

of this AD when they are not. The FAA

finds that, even though the effectivity

listings of the referenced alert service

bulletins specify such an exception,

referencing the alert service bulletins

alone could lead to a misinterpretation.

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 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 shall identify the
Federal Register / Vol. 62, No. 77 / Tuesday, April 22, 1997 / Rules and Regulations 19479

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–61–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 39–9638 (61 FR

27251, May 31, 1996), and by adding a

new airworthiness directive (AD),

amendment 39–9995, to read as follows:

97–08–07 McDonnell Douglas: Amendment

39–9995. Docket 97–NM–61–AD.

Supersedes AD 96–11–13, Amendment

39–9638.

Applicability: Model DC–9–81 (MD–81),

DC–9–82 (MD–82), DC–9–83 (MD–83), and

DC–9–87 (MD–87) and Model MD–88

airplanes, excluding airplanes equipped with

solid state electronic light ballasts;

certificated in any category; and listed in the

following McDonnell Douglas Service

Bulletins:

• Both McDonnell Douglas Alert Service

Bulletin MD80–33A107, dated April 25,

1996, and McDonnell Douglas Alert Service

Bulletin MD80–25A353, dated March 14,

1996.

Or

• McDonnell Douglas Alert Service

Bulletin MD80–33A110, dated February 25,

1997.

Or

• McDonnell Douglas Alert Service

Bulletin MD80–33A110, Revision 1, dated

March 11, 1997.

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 (e) 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 failure of the fluorescent light

ballast of the upper and lower cabin sidewall,

and consequent failure of the dust barriers of

the outboard ceiling panel, accomplish the

following:

(a) For airplanes listed in McDonnell

Douglas Alert Service Bulletin MD80–

33A107, dated April 25, 1996, and

McDonnell Douglas Alert Service Bulletin

MD80–25A353, dated March 14, 1996:

Within 90 days after June 17, 1996 (the

effective date of AD 96–11–13, amendment

39–9638), perform a one-time visual

inspection to determine the type of

fluorescent light ballasts installed in the

upper and lower cabin sidewall, in

accordance with McDonnell Douglas Alert

Service Bulletin MD80–33A107, dated April

25, 1996.

Note 2: Inspections accomplished prior to

the effective date of this AD in accordance

with McDonnell Douglas Alert Service

Bulletin MD80–33A110, dated February 25,

1997, or Revision 1, dated March 3, 1997; are

considered acceptable for compliance with

the visual inspection required by paragraph

(a) of this AD.

(1) If any Bruce Industries Incorporated

ballast is installed (specified as Condition 1

in the alert service bulletin), no further action

is required by this paragraph for that ballast.

(2) If any Day-Ray Products Incorporated

ballast is installed (specified as Condition 2

in the alert service bulletin), prior to further

flight, accomplish either paragraph (a)(2)(i) or

(a)(2)(ii) of this AD.

(i) Replace it with a Bruce Industries

Incorporated ballast, in accordance with

Condition 2, Option 2, of the alert service

bulletin. Or

Note 3: Replacements accomplished prior

to the effective date of this AD in accordance

with McDonnell Douglas Alert Service

Bulletin MD80–33A110, dated February 25,

1997, or Revision 1, dated March 3, 1997, are

considered acceptable for compliance with

the replacement required by paragraph

(a)(2)(i) of this AD.

(ii) Remove or disconnect it electrically,

stow it, and protect the loose wiring.

(b) For airplanes having manufacturer’s

fuselage numbers listed in McDonnell

Douglas Alert Service Bulletin MD80–

25A353, dated March 14, 1996: Within 90

days after June 17, 1996, remove the dust

barriers from the outboard ceiling panels, and

install modified outboard ceiling panels, in

accordance with McDonnell Douglas Alert

Service Bulletin MD80–25A353, dated March

14, 1996.

(c) For airplanes on which the installation

of a protective cover, as described in

McDonnell Douglas Alert Service Bulletin

MD80–33A107, dated April 25, 1996, has

been accomplished [required by paragraph

(a)(2)(i) of AD 96–11–13]: Within 90 days

after the effective date of this AD, accomplish

paragraph (c)(1), (c)(2), or (c)(3) of this AD.

(1) Replace the Day-Ray Products

Incorporated ballast and protective cover

with a Bruce Industries Incorporated ballast,

in accordance with Condition 2 of the

Accomplishment Instructions of Boeing Alert

Service Bulletin MD80–33A110, dated

February 25, 1997, or Revision 1, dated

March 11, 1997. Or

(2) Replace the Day-Ray Products

Incorporated ballast and protective cover
19480 Federal Register / Vol. 62, No. 77 / Tuesday, April 22, 1997 / Rules and Regulations

with an FAA-approved solid state electronic

light ballast system, in accordance with an

applicable Supplemental Type Certificate

(STC) or other method approved by the

Manager, Los Angeles Aircraft Certification

Office (ACO), FAA, Transport Airplane

Directorate. Or

(3) Remove the Day-Ray Products

Incorporated ballast and protective cover or

disconnect it electrically, stow it, and protect

the loose wiring.

(d) As of the effective date of this AD, no

Day-Ray Products Incorporated ballast,

having any part number identified in

paragraph 1.2 of McDonnell Douglas Alert

Service Bulletin MD80–33A107, dated April

25, 1996, McDonnell Douglas Alert Service

Bulletin MD80–33A110, dated February 25,

1997, or McDonnell Douglas Alert Service

Bulletin MD80–33A110, Revision 1, dated

March 11, 1997, shall be installed on any

airplane.

(e)(1) 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, Los

Angeles ACO. Operators shall submit their

requests through an appropriate FAA

Principal Maintenance Inspector, who may

add comments and then send it to the

Manager, Los Angeles ACO.

Note 4: Information concerning the

existence of approved alternative methods of

compliance with this AD, if any, may be

obtained from the Los Angeles ACO.

(2) Alternative methods of compliance,

approved previously in accordance with AD

96–11–13, amendment 39–9638, are

approved as alternative methods of

compliance with this AD.

(f) 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.

(g) The inspection and replacement shall

be done in accordance with McDonnell

Douglas Alert Service Bulletin MD80–

33A107, dated April 25, 1996; McDonnell

Douglas Alert Service Bulletin MD80–

33A110, dated February 25, 1997; and

McDonnell Douglas Alert Service Bulletin

MD80–33A110, Revision 1, dated March 11,

1997. The removal of the dust barriers and

installations shall be done in accordance

with McDonnell Douglas Alert Service

Bulletin MD80–25A353, dated March 14,

1996. The incorporation by reference of

McDonnell Douglas Alert Service Bulletin

MD80–33A107, dated April 25, 1996, and

McDonnell Douglas Alert Service Bulletin

MD80–25A353, dated March 14, 1996, 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 June 17, 1996

(61 FR 27251, May 31, 1996). The

incorporation by reference of the remainder

of the service documents listed above is

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 McDonnell Douglas Corporation, 3855

Lakewood Boulevard, Long Beach, California

90846, Attention: Technical Publications

Business Administration, Department C1–

L51 (2–60). Copies may be inspected at the

FAA, Transport Airplane Directorate, 1601

Lind Avenue, SW., Renton, Washington; or at

the FAA, Transport Airplane Directorate, Los

Angeles Aircraft Certification Office, 3960

Paramount Boulevard, Lakewood, California;

or at the Office of the Federal Register, 800

North Capitol Street, NW., suite 700,

Washington, DC.

(h) This amendment becomes effective on

May 7, 1997.

Issued in Renton, Washington, on April 9,

1997.

Darrell M. Pederson,

Acting Manager, Transport Airplane

Directorate, Aircraft Certification Service.

[FR Doc. 97–9710 Filed 4–21–97; 8:45 am]

BILLING CODE 4910–13–U

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 97–NM–60–AD; Amendment

39–9996; AD 97–08–08]

RIN 2120–AA64

Airworthiness Directives; Boeing

Model 777–200 Series Airplanes

AGENCY: Federal Aviation

Administration, DOT.

ACTION: Final rule; request for

comments.

SUMMARY: This amendment adopts a

new airworthiness directive (AD),

applicable to certain Boeing Model 777–

200 series airplanes. This action

requires repetitive visual inspections of

the forward mounts of certain engines to

detect damaged, missing, or failed parts,

and eventual modification of those

engines. Accomplishment of this

modification terminates the requirement

for repetitive inspections. This

amendment is prompted by a report

indicating that bolts that attach the yoke

of the forward mount to the fan case of

the engine have failed due to fatigue

cracking. The actions specified in this

AD are intended to prevent fatigue

cracking in these bolts, which could

lead to failure of these bolts and

consequent separation of the engine

from the wing.

DATES: Effective May 7, 1997. The

incorporation by reference of certain

publications listed in the regulations is

approved by the Director of the Federal

Register as of May 7, 1997.

Comments for inclusion in the Rules

Docket must be received on or before

June 23, 1997.

ADDRESSES: Submit comments in

triplicate to the Federal Aviation

Administration (FAA), Transport

Airplane Directorate, ANM–103,

Attention: Rules Docket No. 97–NM–

60–AD, 1601 Lind Avenue, SW.,

Renton, Washington 98055–4056.

The service information referenced in

this AD may be obtained from General

Electric Aircraft Engines, GE90 Product

Support, One Neuman Way, Cincinnati,

Ohio 45215–6301. 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: Stan

Wood, Aerospace Engineer, Airframe

Branch, ANM–120S, FAA, Seattle

Aircraft Certification Office, 1601 Lind

Avenue, SW., Renton, Washington;

telephone (206) 227–2772; fax (206)

227–1181.

SUPPLEMENTARY INFORMATION: During

certification testing of the General

Electric (GE) 90 engine, fatigue cracking

was detected in the bolts that attach the

yoke of the forward mount of the engine

to the fan case of the engine. Fatigue

cracking in the bolts that attach the yoke

of the forward mount of the engine to

the fan case of the engine, if not

prevented, could lead to failure of these

bolts and consequent separation of the

engine from the wing.

An analysis revealed that these bolts

had a short fatigue life due to the large

forces that the yoke exerted on them. As

a result, the original yoke design was

not certified as meeting the damage

tolerance standards of part 25 of the

Federal Aviation Regulations (14 CFR

part 25). The engine manufacturer

subsequently redesigned the yoke and

fan case to those standards in order to

prevent fatigue cracking in the bolts.

Although the airplane manufacturer

did not install GE90 engines with the

original yoke design on any Model 777–

200 series airplanes, the engine

manufacturer shipped some of these

engines to operators as replacement

engines. The engine manufacturer had

apparently concluded, in error, that if

the yoke complied with the strength

requirements of part 33 of the Federal

Aviation Regulations (14 CFR part 33),

it could ship engines containing yokes

of the original design for use as spare

engines for these airplanes. The yoke

must, in fact, meet both the strength

standards of part 33 and the damage

tolerance standards of part 25 in order

to be certificated for installation on the

Boeing Model 777–200 series airplane.

The discrepant yokes are installed in

GE90 engines having serial numbers

900–104, –105, –106, –108, –109, –110,

and –111.