42208 Federal Register / Vol. 63, No. 152 / Friday, August 7, 1998 /Rules and Regulations

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:

98–16–17 Cessna Aircraft Company:

Amendment 39–10693. Docket 98–NM–

208–AD.

Applicability: All Model 750 Citation X

series airplanes, 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 (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 detect and correct internal water

contamination and corrosion damage of the

secondary horizontal stabilizer trim actuator,

which could result in simultaneous failure of

both primary and secondary pitch trim

systems, and consequent reduced

controllability of the airplane, accomplish

the following:

(a) Within 10 days after the effective date

of this AD, perform an in-flight functional

test to verify proper operation of the

secondary horizontal stabilizer pitch trim

system, in accordance with Cessna Alert

Service Bulletin ASB750–27–22, dated July

2, 1998.

(1) If the secondary trim system does not

fail during the in-flight functional test, repeat

the action thereafter at intervals not to exceed

30 days.

(2) If the secondary trim system fails

during the in-flight functional test, prior to

next flight, inspect the actuator components

and clutch assemblies for evidence of

internal water contamination or corrosion

damage in accordance with the alert service

bulletin. If any evidence of internal water

contamination or corrosion damage is

detected, prior to further flight, repair in

accordance with the alert service bulletin.

Repeat the in-flight functional test thereafter

at intervals not to exceed 30 days.

(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, Wichita

Aircraft Certification Office (ACO), FAA,

Small 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, Wichita ACO.

Note 2: Information concerning the

existence of approved alternative methods of

compliance with this AD, if any, may be

obtained from the Wichita ACO.

(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

can be accomplished.

(d) The actions shall be done in accordance

with Cessna Alert Service Bulletin ASB750–

27–22, dated July 2, 1998. 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 Cessna Aircraft Co., P.O.

Box 7706, Wichita, Kansas 67277. Copies

may be inspected at the FAA, Transport

Airplane Directorate, 1601 Lind Avenue,

SW., Renton, Washington; or at the FAA,

Small Airplane Directorate, Wichita Aircraft

Certification Office, 1801 Airport Road,

Room 100, Mid-Continent Airport, Wichita,

Kansas; or at the Office of the Federal

Register, 800 North Capitol Street, NW., suite

700, Washington, DC.

(e) This amendment becomes effective on

August 24, 1998.

Issued in Renton, Washington, on July 29,

1998.

Darrell M. Pederson,

Acting Manager, Transport Airplane

Directorate, Aircraft Certification Service.

[FR Doc. 98–20836 Filed 8–6–98; 8:45 am]

BILLING CODE 4910–13–U

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98–NM–227–AD; Amendment

39–10694; AD 98–16–18]

RIN 2120–AA64

Airworthiness Directives; Learjet

Model 60 Airplanes

AGENCY: Federal Aviation

Administration, DOT.

ACTION: Final rule; request for

comments.

SUMMARY: This amendment adopts a

new airworthiness directive (AD) that is

applicable to certain Learjet Model 60

airplanes. This action requires repetitive

measurements of the brake wear

dimension between the housing

subassembly and the pressure plate that

is adjacent to the top pistons of the

brake assembly; and follow-on

corrective actions, if necessary. This

amendment is prompted by reports of

abnormal (uneven) brake wear. The

actions specified in this AD are

intended to detect and repair an

abnormal brake wear condition, which

could result in loss of brake

effectiveness and cause the airplane to

leave the runway surface.

DATES: Effective August 24, 1998.

The incorporation by reference of

certain publications listed in the

regulations is approved by the Director

of the Federal Register as of August 24,

1998.

Comments for inclusion in the Rules

Docket must be received on or before

October 6, 1998.

ADDRESSES: Submit comments in

triplicate to the Federal Aviation

Administration (FAA), Transport

Airplane Directorate, ANM–114,

Attention: Rules Docket No. 98–NM–

227–AD, 1601 Lind Avenue, SW.,

Renton, Washington 98055–4056.

The service information referenced in

this AD may be obtained from Aircraft

Braking Systems Corporation, 1204

Massillon, Akron, Ohio 44306. This

information may be examined at the

FAA, Transport Airplane Directorate,

1601 Lind Avenue, SW., Renton,

Washington; or at the FAA, Small

Airplane Directorate, Wichita Aircraft

Certification Office, 1801 Airport Road,

Room 100, Mid-Continent Airport,

Wichita, Kansas; or at the Office of the

Federal Register, 800 North Capitol

Street, NW., suite 700, Washington, DC.

FOR FURTHER INFORMATION CONTACT: Paul

C. DeVore, Aerospace Engineer, Systems

and Propulsion Branch, ACE–116W,

FAA, Small Airplane Directorate,

Wichita Aircraft Certification Office,

1801 Airport Road, Room 100, MidContinent Airport, Wichita, Kansas

67209; telephone (316) 946–4142; fax

(316) 946–4407.

SUPPLEMENTARY INFORMATION: The FAA

has received reports from Learjet of an

abnormal brake wear condition on

certain Learjet Model 60 airplanes.

Subsequent investigation, conducted by

Aircraft Braking Systems Corporation

(ABS) (the manufacturer of the brakes),

revealed an abnormal (uneven) brake
Federal Register / Vol. 63, No. 152 / Friday, August 7, 1998 /Rules and Regulations 42209

wear condition of the friction material

(friction mix) on the rotating disks. The

uneven wear has been attributed to

thermal gradients within the brake stack

of the ABS brake assembly. Such

abnormal brake wear, if not corrected,

could result in loss of brake

effectiveness, which could cause the

airplane to leave the runway surface.

Explanation of Relevant Service

Information

The FAA has reviewed Aircraft

Braking Systems Service Bulletin

LEAR60–32–03, dated March 5, 1998,

which describes procedures for

repetitive measurements of the brake

wear dimension between the housing

subassembly and the pressure plate that

is adjacent to the top pistons of the

brake assembly; and follow-on

corrective actions, if necessary. These

follow-on actions include performing a

visual inspection to detect abnormal

wear of the friction mix on the rotating

disks, and replacing both rotating disks

with new disks, if necessary; and

replacing the disk stack with a new disk

stack or overhauling it.

Accomplishment of certain actions

specified in the service bulletin is

intended to adequately address the

identified unsafe condition.

Explanation of the Requirements of the

Rule

Since an unsafe condition has been

identified that is likely to exist or

develop on other airplanes of the same

type design, this AD is being issued to

detect and repair an abnormal (uneven)

brake wear condition, which could

result in loss of brake effectiveness and

cause the airplane to leave the runway

surface. This AD requires

accomplishment of certain actions

specified in the service bulletin

described previously.

Operators should note that the service

bulletin lists other actions in addition to

those described previously. The FAA

considers these additional actions to be

routine maintenance and therefore has

not specified their performance in this

AD.

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

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 98–NM–227–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

adding the following new airworthiness

directive:

98–16–18 Learjet: Amendment 39–10694.

Docket 98–NM–227–AD.

Applicability: Model 60 airplanes

equipped with Aircraft Braking Systems

(ABS) brake assemblies having part number

5003096–7, 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 (c) 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 detect and repair an abnormal (uneven)

brake wear condition, which could result in

loss of brake effectiveness and cause the

airplane to leave the runway surface,

accomplish the following:

(a) Within 10 flight hours after the effective

date of this AD, measure the brake wear

dimension between the housing subassembly

and the pressure plate that is adjacent to the

top pistons of the brake assembly, in

accordance with ABS Service Bulletin

LEAR60–32–03, dated March 5, 1998.

(1) If the dimension is less than 0.359 inch

(9.12 mm), thereafter repeat the measurement

at intervals not to exceed 25 flight cycles.
42210 Federal Register / Vol. 63, No. 152 / Friday, August 7, 1998 /Rules and Regulations

(2) If the dimension is equal to or greater

than 0.359 inch (9.12 mm) and less than

0.464 inch (11.79 mm), prior to further flight,

perform a visual inspection to detect

abnormal wear of the friction mix on the

rotating disks, in accordance with the service

bulletin.

(i) If the friction mix is not worn to the disk

cores on either disk, thereafter repeat the

measurement at intervals not to exceed 25

flight cycles.

(ii) If the friction mix is worn to the disk

core on either disk, replace both rotating

disks with new disks in accordance with the

service bulletin. Thereafter, repeat the

measurement at intervals not to exceed 25

flight cycles.

(3) If the dimension is greater than or equal

to 0.464 inch (11.769 mm), replace the disk

stack with a new disk stack or overhaul it,

in accordance with the service bulletin.

Thereafter, repeat the measurement at

intervals not to exceed 25 flight cycles.

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

person shall install on any airplane a used

ABS brake assembly, part number 5003096–

7, unless it has been inspected and

applicable corrective actions have been

performed in accordance with the

requirements of this AD.

(c) 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, Wichita

Aircraft Certification Office (ACO), FAA,

Small 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, Wichita ACO.

Note 2: Information concerning the

existence of approved alternative methods of

compliance with this AD, if any, may be

obtained from the Wichita ACO.

(d) 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.

(e) The actions shall be done in accordance

with Aircraft Braking Systems Corporation

Service Bulletin LEAR60–32–03, dated

March 5, 1998. 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 Learjet, Inc., One Learjet Way,

Wichita, Kansas 67209–2942. Copies may be

inspected at the FAA, Transport Airplane

Directorate, 1601 Lind Avenue, SW., Renton,

Washington; or at the FAA, Small Airplane

Directorate, Wichita Aircraft Certification

Office, 1801 Airport Road, Room 100, MidContinent Airport, Wichita, Kansas; or at the

Office of the Federal Register, 800 North

Capitol Street, NW., suite 700, Washington,

DC.

(f) This amendment becomes effective on

August 24, 1998.

Issued in Renton, Washington, on July 30,

1998.

Darrell M. Pederson,

Acting Manager, Transport Airplane

Directorate, Aircraft Certification Service.

[FR Doc. 98–20970 Filed 8–6–98; 8:45 am]

BILLING CODE 4910–13–P

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98–NM–180–AD; Amendment

39–10695; AD 98–16–19]

RIN 2120–AA64

Airworthiness Directives; Boeing

Model 747 Series Airplanes

AGENCY: Federal Aviation

Administration, DOT.

ACTION: Final rule; request for

comments.

SUMMARY: This amendment adopts a

new airworthiness directive (AD) that is

applicable to all Boeing Model 747

series airplanes. This action requires, for

certain airplanes, revising the Airplane

Flight Manual (AFM) to advise the

flightcrew of limitations on dry (no fuel)

operation of the override/jettison pumps

of the center wing fuel tank. This action

also requires repetitive inspections for

wear or damage of the inlet check valves

and inlet adapters of the override/

jettison pumps, and replacement of the

check valves and pumps with new or

serviceable parts, if necessary. Such

replacement terminates the AFM

revision. This amendment is prompted

by a report that inlet adapters of

override/jettison pumps were found to

be worn excessively, which allowed

contact to occur between the inlet check

valve and the inducer. The actions

specified in this AD are intended to

ensure that the flightcrew is advised of

the hazards of dry operation of the

override/jettison pumps of the center

wing fuel tank, and to detect and correct

wear or damage to the inlet check valves

and inlet adapters of the override/

jettison pumps; such conditions, if not

corrected, could result in a fire or

explosion in the fuel tank during dry

operation.

DATES: Effective August 24, 1998.

The incorporation by reference of

certain publications listed in the

regulations is approved by the Director

of the Federal Register as of August 24,

1998.

Comments for inclusion in the Rules

Docket must be received on or before

October 6, 1998.

ADDRESSES: Submit comments in

triplicate to the Federal Aviation

Administration (FAA), Transport

Airplane Directorate, ANM–114,

Attention: Rules Docket No. 98–NM–

180–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:

Sulmo Mariano, Aerospace Engineer,

Propulsion Branch, ANM–140S, FAA,

Transport Airplane Directorate, Seattle

Aircraft Certification Office, 1601 Lind

Avenue, SW., Renton, Washington

98055–4056; telephone (425) 227–2686;

fax (425) 227–1181.

SUPPLEMENTARY INFORMATION: The FAA

has received a report indicating that,

during an inspection of the fuel system

on a Boeing Model 747–400 series

airplane, inlet adapters of the override/

jettison pumps of the center wing fuel

tank were found to be worn. Two of the

inlet adapters had worn down enough to

cause damage to the rotating blades of

the inducer. The inlet check valves also

had significant damage. Another

operator reported damage to the inlet

adapter that was so severe that contact

had occurred between the steel disk of

the inlet check valve and the steel screw

that holds the inducer in place. (Such

wear conditions were not found on the

override/jettison pumps of the center

wing fuel tank that were recovered from

a Model 747–400 series airplane

involved in an accident, in which the

airplane broke up shortly after takeoff

from John F. Kennedy International

Airport in Jamaica, New York, on July

17, 1996. In addition, those pumps are

not believed to have been operating on

the accident airplane during that flight

because mission fuel had not been

loaded into the center tank.)

Wear to the inlet adapters has been

attributed to contact between the inlet

check valve and the adapter. Vibration,

possibly due to oscillations of the fuel

flow, causes wear to both the stainless

steel disk of the inlet check valve and

the inlet adapter. The wear to the inlet

adapter is accelerated by the steel disk

of the check valve chafing against the

edge of the adapter. Such excessive

wear of the inlet adapter can lead to

contact between the inlet check valve

and inducer, which could result in

pieces of the check valve being ingested