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

16113

Vol. 62, No. 65

Friday, April 4, 1997

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 96–NM–178–AD]

RIN 2120–AA64

Airworthiness Directives; Jetstream

Model ATP Airplanes

AGENCY: Federal Aviation

Administration, DOT.

ACTION: Notice of proposed rulemaking

(NPRM).

SUMMARY: This document proposes the

adoption of a new airworthiness

directive (AD) that is applicable to

certain Jetstream Model ATP airplanes.

This proposal would require

modification of the hydraulic system,

and a revision to the Airplane Flight

Manual (AFM) to include revised

procedures for lowering the landing

gear. This proposal is prompted by a

report of uncommanded application of

the brakes when the direct current (DC)

hydraulic pump was selected ON with

the main hydraulic system operative;

this situation was caused by build-up of

back pressure in the brake supply and

hydraulic return systems. The actions

specified by the proposed AD are

intended to prevent uncommanded

application of the brakes during

landing, as a result of the build-up of

back pressure.

DATES: Comments must be received by

May 15, 1997.

ADDRESSES: Submit comments in

triplicate to the Federal Aviation

Administration (FAA), Transport

Airplane Directorate, ANM–103,

Attention: Rules Docket No. 96–NM–

178–AD, 1601 Lind Avenue, SW.,

Renton, Washington 98055–4056.

Comments may be inspected at this

location between 9:00 a.m. and 3:00

p.m., Monday through Friday, except

Federal holidays.

The service information referenced in

the proposed rule may be obtained from

Jetstream Aircraft, Inc., P.O. Box 16029,

Dulles International Airport,

Washington, DC 20041–6029. This

information may be examined at the

FAA, Transport Airplane Directorate,

1601 Lind Avenue, SW., Renton,

Washington.

FOR FURTHER INFORMATION CONTACT:

William Schroeder, Aerospace Engineer,

Standardization Branch, ANM–113,

FAA, Transport Airplane Directorate,

1601 Lind Avenue, SW., Renton,

Washington 98055–4056; telephone

(206) 227–2148; fax (206) 227–1149.

SUPPLEMENTARY INFORMATION:

Comments Invited

Interested persons are invited to

participate in the making of the

proposed rule by submitting such

written data, views, or arguments as

they may desire. Communications shall

identify the Rules Docket number and

be submitted in triplicate to the address

specified above. All communications

received on or before the closing date

for comments, specified above, will be

considered before taking action on the

proposed rule. The proposals contained

in this notice may be changed in light

of the comments received.

Comments are specifically invited on

the overall regulatory, economic,

environmental, and energy aspects of

the proposed rule. All comments

submitted will be available, both before

and after the closing date for comments,

in the Rules Docket for examination by

interested persons. A report

summarizing each FAA-public contact

concerned with the substance of this

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 96–NM–178–AD.’’ The

postcard will be date stamped and

returned to the commenter.

Availability of NPRMs

Any person may obtain a copy of this

NPRM by submitting a request to the

FAA, Transport Airplane Directorate,

ANM–103, Attention: Rules Docket No.

96-NM–178-AD, 1601 Lind Avenue,

SW., Renton, Washington 98055–4056.

Discussion

The Civil Aviation Authority (CAA),

which is the airworthiness authority for

the United Kingdom, notified the FAA

that an unsafe condition may exist on

certain Jetstream Model ATP airplanes.

The CAA advises that it has received a

report of uncommanded application of

the brakes when the direct current (DC)

hydraulic pump of the auxiliary

hydraulic system was selected ON with

the main hydraulic system operative.

The cause has been attributed to the

build-up of back pressure in the brake

supply and hydraulic return systems, as

a result of installation of Jetstream

Modification 10303A. (The existing

design of Modification 10303A does not

account for the fact that the auxiliary

hydraulic system may be operated while

the main hydraulic system is operating.)

Build-up of back pressure in the brake

supply and hydraulic return systems, if

not corrected, could result in

uncommanded application of the brakes

during landing.

Explanation of Relevant Service

Information

Jetstream has issued Service Bulletin

ATP–29–12, dated September 9, 1995,

which describes procedures for

revisions to the Emergency and

Abnormal Procedures Sections of the

Airplane Flight Manual (AFM) to

include revised procedures for lowering

the landing gear. (Paragraph 1.K. of the

service bulletin references Temporary

Revision No. T/52 as an additional

source of service information for

revising the AFM. This particular

Temporary Revision applies to airplanes

of U.S. registry.)

The service bulletin also describes

procedures for modification of the

hydraulic system. The modification

involves:

1. Connecting the auxiliary hydraulic

reservoir feed to the main hydraulic

return system, thus eliminating the need

for a check valve (HTE 510013) and its

associated piping;

2. Connecting the existing feed line of

the auxiliary reservoir directly to the

pressure bleed line of the brake master

cylinder;

3. Installing a non-return valve

between the change-over isolation valve

and the main pressure manifold; and

4. Removing the bypass pipeline of

the landing gear. Accomplishment of

the modification will prevent
16114 Federal Register / Vol. 62, No. 65 / Friday, April 4, 1997 / Proposed Rules

uncommanded application of the brakes

during landing when the DC hydraulic

pump is selected ON with the main

hydraulic system operative.

The CAA classified this service

bulletin as mandatory and issued British

airworthiness directive 001–09–095,

dated September 1995, in order to

assure the continued airworthiness of

these airplanes in the United Kingdom.

FAA’s Conclusions

This airplane model is manufactured

in the United Kingdom and is type

certificated for operation in the United

States under the provisions of section

21.29 of the Federal Aviation

Regulations (14 CFR 21.29) and the

applicable bilateral airworthiness

agreement. Pursuant to this bilateral

airworthiness agreement, the CAA has

kept the FAA informed of the situation

described above. The FAA has

examined the findings of the CAA,

reviewed all available information, and

determined that AD action is necessary

for products of this type design that are

certificated for operation in the United

States.

Explanation of Requirements of

Proposed Rule

Since an unsafe condition has been

identified that is likely to exist or

develop on other airplanes of the same

type design registered in the United

States, the proposed AD would require

modification of the hydraulic system.

The proposed AD also would require

revisions to the Emergency and

Abnormal Procedures Sections of the

FAA-approved AFM to include revised

procedures for lowering the landing

gear. The actions would be required to

be accomplished in accordance with the

service bulletin described previously.

Cost Impact

The FAA estimates that 10 Jetstream

Model ATP airplanes of U.S. registry

would be affected by this proposed AD.

It would take approximately 25 work

hours per airplane to accomplish the

proposed modification, at an average

labor rate of $60 per work hour.

Required parts will be provided by the

manufacturer at no cost to the operator.

Based on these figures, the cost impact

of the modification proposed by this AD

on U.S. operators is estimated to be

$15,000, or $1,500 per airplane.

It would take approximately 1 work

hour per airplane to accomplish the

proposed AFM revisions, at an average

labor rate of $60 per work hour. Based

on these figures, the cost impact of the

AFM revisions proposed by this AD on

U.S. operators is estimated to be $600,

or $60 per airplane.

The cost impact figures discussed

above are based on assumptions that no

operator has yet accomplished any of

the proposed requirements of this AD

action, and that no operator would

accomplish those actions in the future if

this AD were not adopted.

Regulatory Impact

The regulations proposed herein

would not have substantial direct effects

on the States, on the relationship

between the national government and

the States, or on the distribution of

power and responsibilities among the

various levels of government. Therefore,

in accordance with Executive Order

12612, it is determined that this

proposal would not have sufficient

federalism implications to warrant the

preparation of a Federalism Assessment.

For the reasons discussed above, I

certify that this proposed regulation (1)

is not a ‘‘significant regulatory action’’

under Executive Order 12866; (2) is not

a ‘‘significant rule’’ under the DOT

Regulatory Policies and Procedures (44

FR 11034, February 26, 1979); and (3) if

promulgated, will not have a significant

economic impact, positive or negative,

on a substantial number of small entities

under the criteria of the Regulatory

Flexibility Act. A copy of the draft

regulatory evaluation prepared for this

action is contained in the Rules Docket.

A copy of it may be obtained by

contacting the Rules Docket at the

location provided under the caption

‘‘ADDRESSES.’’

List of Subjects in 14 CFR Part 39

Air transportation, Aircraft, Aviation

safety, Safety.

The Proposed Amendment

Accordingly, pursuant to the

authority delegated to me by the

Administrator, the Federal Aviation

Administration proposes to amend part

39 of the Federal Aviation Regulations

(14 CFR part 39) as follows:

PART 39—AIRWORTHINESS

DIRECTIVES

1. The authority citation for part 39

continues to read as follows:

Authority: 49 U.S.C. 106(g), 40113, 44701.

§ 39.13—[Amended]

2. Section 39.13 is amended by

adding the following new airworthiness

directive:

Jetstream Aircraft Limited: Docket 96–NM–

178–AD.

Applicability: Model ATP airplanes,

having constructor’s numbers 2002 through

2063 inclusive; on which Jetstream

Modification 10303A (Jetstream Service

Bulletin ATP 32–41) has been installed;

certificated in any category.

Note 1: This AD applies to each airplane

identified in the preceding applicability

provision, regardless of whether it has been

otherwise modified, altered, or repaired in

the area subject to the requirements of this

AD. For airplanes that have been modified,

altered, or repaired so that the performance

of the requirements of this AD is affected, the

owner/operator must request approval for an

alternative method of compliance in

accordance with paragraph (b) of this AD.

The request should include an assessment of

the effect of the modification, alteration, or

repair on the unsafe condition addressed by

this AD; and, if the unsafe condition has not

been eliminated, the request should include

specific proposed actions to address it.

Compliance: Required as indicated, unless

accomplished previously.

To prevent uncommanded application of

the brakes during landing, accomplish the

following:

(a) Within 60 days of the effective date of

this AD, accomplish paragraphs (a)(1) and

(a)(2) of this AD in accordance with Jetstream

Service Bulletin ATP–29–12, dated

September 9, 1995.

(1) Modify the hydraulic system; and

(2) Revise the Emergency and Abnormal

Procedures Sections of the FAA-approved

Airplane Flight Manual (AFM) to include the

information specified in Temporary Revision

No. T/52, Issue 1, dated August 16, 1995,

which introduces revised procedures for

lowering the landing gear, as specified in the

temporary revision; and operate the airplane

in accordance with those limitations and

procedures.

Note 2: Paragraph 1.K. of Jetstream Service

Bulletin ATP–29–12, dated September 9,

1995, references Temporary Revision No. T/

52 as an additional source of service

information for revising the AFM.

Note 3: This may be accomplished by

inserting a copy of Temporary Revision No.

T/52 in the AFM. When this temporary

revision has been incorporated into general

revisions of the AFM, the general revisions

may be inserted in the AFM, provided the

information contained in the general

revisions is identical to that specified in

Temporary Revision No. T/52.

(b) An alternative method of compliance or

adjustment of the compliance time that

provides an acceptable level of safety may be

used if approved by the Manager,

Standardization Branch, ANM–113, 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, Standardization

Branch, ANM–113.

Note 4: Information concerning the

existence of approved alternative methods of

compliance with this AD, if any, may be

obtained from the Standardization Branch,

ANM–113.

(c) Special flight permits may be issued in

accordance with sections 21.197 and 21.199

of the Federal Aviation Regulations (14 CFR

21.197 and 21.199) to operate the airplane to

a location where the requirements of this AD
Federal Register / Vol. 62, No. 65 / Friday, April 4, 1997 / Proposed Rules 16115

can be accomplished. Issued in Renton,

Washington, on March 31, 1997.

S. R. Miller,

Acting Manager, Transport Airplane

Directorate, Aircraft Certification Service.

[FR Doc. 97–8700 Filed 4–3–97; 8:45 am]

BILLING CODE 4910–13–U

14 CFR Part 39

[Docket No. 97–NM–55–AD]

RIN 2120–AA64

Airworthiness Directives; Boeing

Model 777–200 Series Airplanes

AGENCY: Federal Aviation

Administration, DOT.

ACTION: Notice of proposed rulemaking

(NPRM).

SUMMARY: This document proposes the

adoption of a new airworthiness

directive (AD) that is applicable to

certain Boeing Model 777–200 series

airplanes. This proposal would require

replacement of certain overhead

electronics units (OEU) of the passenger

address and entertainment

communication systems with modified

OEU’s. This proposal is prompted by

reports of smoke coming from the

overhead panels near the passenger

reading lights, which was caused by

overheating of the transformers located

in the OEU’s. The actions specified by

the proposed AD are intended to

prevent overheating of the transformers,

which potentially could cause a fire in

the transformer assembly and/or

electronic components located in the

OEU and could cause smoke to enter the

passenger cabin.

DATES: Comments must be received by

May 15, 1997.

ADDRESSES: Submit comments in

triplicate to the Federal Aviation

Administration (FAA), Transport

Airplane Directorate, ANM–103,

Attention: Rules Docket No. 97–NM–

55–AD, 1601 Lind Avenue, SW.,

Renton, Washington 98055–4056.

Comments may be inspected at this

location between 9:00 a.m. and 3:00

p.m., Monday through Friday, except

Federal holidays.

The service information referenced in

the proposed rule 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.

FOR FURTHER INFORMATION CONTACT:

Peter Skaves, Aerospace Engineer,

Systems and Equipment Branch, ANM–

130S, FAA, Seattle Aircraft Certification

Office, 1601 Lind Avenue, SW., Renton,

Washington; telephone (206) 227–2795;

fax (206) 227–1181.

SUPPLEMENTARY INFORMATION:

Comments Invited

Interested persons are invited to

participate in the making of the

proposed rule by submitting such

written data, views, or arguments as

they may desire. Communications shall

identify the Rules Docket number and

be submitted in triplicate to the address

specified above. All communications

received on or before the closing date

for comments, specified above, will be

considered before taking action on the

proposed rule.

The proposals contained in this notice

may be changed in light of the

comments received.

Comments are specifically invited on

the overall regulatory, economic,

environmental, and energy aspects of

the proposed rule. All comments

submitted will be available, both before

and after the closing date for comments,

in the Rules Docket for examination by

interested persons. A report

summarizing each FAA-public contact

concerned with the substance of this

proposal will be filed in the Rules

Docket.

Commenters wishing the FAA to

acknowledge receipt of their comments

submitted in response to this notice

must submit a self-addressed, stamped

postcard on which the following

statement is made: ‘‘Comments to

Docket Number 97–NM–55–AD.’’ The

postcard will be date stamped and

returned to the commenter.

Availability of NPRMs

Any person may obtain a copy of this

NPRM by submitting a request to the

FAA, Transport Airplane Directorate,

ANM–103, Attention: Rules Docket No.

97–NM–55–AD, 1601 Lind Avenue,

SW., Renton, Washington 98055–4056.

Discussion

The FAA has received several reports

of smoke coming from the overhead

panel near the passenger reading lights

on Boeing Model 777–200 series

airplanes. In other reports, the overhead

electronics units (OEU) failed to supply

power to the lights of the passenger

cabin. Investigation revealed that the

transformers of the OEU’s are not

adequately protected from certain

overload failure modes, which causes

the transformers to overheat.

Overheating of a transformer, if not

corrected, potentially could cause a fire

in the transformer assembly and/or

electronic components located in the

OEU and could cause smoke to enter the

passenger cabin.

Explanation of Relevant Service

Information

The FAA has reviewed and approved

Boeing Alert Service Bulletin 777–

23A0027, dated February 13, 1997. The

alert service bulletin describes

procedures for replacement of OEU’s,

part numbers (P/N) 285W0029–3,

285W0029–3 MOD A, and 285W0029–3

MOD B, of the passenger address and

entertainment communication systems

with modified OEU’s, P/N’s 285W0029–

5, 285W0029–5 MOD A, and

285W0029–5 MOD B. The modified

OEU’s contain a new transformer

assembly that contains circuit

protection for overload conditions,

which will prevent the transformer from

overheating.

The FAA also has reviewed and

approved Boeing Component Service

Bulletin 285W0029–23–01, dated

February 13, 1997, which describes

procedures for reworking OEU’s having

P/N’s 285W0029–3, 285W0029–3 MOD

A, and 285W0029–3 MOD B. The

rework includes replacing the

transformer assembly located in the

OEU with a new OEU, applying dash

number -5, and adding a MOD level

marking (if applicable) to the nameplate

of the OEU.

Explanation of Requirements of

Proposed Rule

Since an unsafe condition has been

identified that is likely to exist or

develop on other products of this same

type design, the proposed AD would

require replacement of certain OEU’s of

the passenger address and

entertainment communication systems

with modified OEU’s. The actions

would be required to be accomplished

in accordance with the alert service

bulletin described previously.

Cost Impact

There are approximately 46 Boeing

Model 777–200 series airplanes of the

affected design in the worldwide fleet.

The FAA estimates that 16 airplanes of

U.S. registry would be affected by this

proposed AD, that it would take

approximately 209 work hours per

airplane to accomplish the proposed

actions, and that the average labor rate

is $60 per work hour. Required parts

would be supplied by the manufacturer

at no cost to the operators. Based on

these figures, the cost impact of the

proposed AD on U.S. operators is

estimated to be $200,640, or $12,540 per

airplane.

The cost impact figure discussed

above is based on assumptions that no