692 Federal Register / Vol. 65, No. 4 / Thursday, January 6, 2000 / Rules and Regulations

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:

99–27–16 CFE Company: Amendment 39–

11497. Docket 99–NE–39–AD.

Applicability: CFE Model CFE738–1–1B

turbofan engines, serial numbers (S/Ns)

105267 through 105339, inclusive. These

engines are installed on but not limited to

Dassault-Breguet Falcon 2000 series aircraft.

Note 1: This airworthiness directive (AD)

applies to each engine 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 engines that

have been modified, altered, or repaired so

that the performance of the requirements of

this AD is affected, the owner/operator must

request approval for an alternative method of

compliance in accordance with paragraph (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 aft HPT cooling plate failure,

which could result in an uncontained engine

failure and damage to the airplane,

accomplish the following:

Inspections and Follow-On Actions

(a) At the next engine shop visit after the

effective date of this AD where the HPT

assembly is sufficiently disassembled to

afford access to the Stage 2 HPT aft cooling

plate, but not later than 4500 part cyclessince-new (CSN), accomplish the following

in accordance with CFE Alert Service

Bulletin (ASB) No. CFE738–A72–8031,

Revision 1, dated June 23, 1999, as follows:

(1) Inspect the stage 2 HPT aft cooling plate

for nicks, dents, and scratches on surface D

in accordance with the requirements of ASB

No. CFE738–A72–8031, paragraph 2.B.(1).

(2) Repair those stage 2 HPT aft cooling

plates with indentation less than 0.003 inch

deep in accordance with ASB No. CFE738–

A72–8031. paragraph 2.B.(1).

(3) Remove from service prior to further

flight those stage 2 HPT aft cooling plates

that have nicks, dents, and/or scratches that

exceed the acceptance limits in accordance

with ASB No. CFE738–A72–8031 paragraph

2.B.(1), and replace with serviceable parts.

(4) Inspect the stage 2 HPT rotor disk post

aft mating surface for raised metal, and

remove raised metal if present in accordance

with ASB No. CFE738–A72–8031, paragraph

2.B.(2).

Alternative Methods of Compliance

(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, Engine

Certification Office (ECO). Operators shall

submit their request through an appropriate

FAA Principal Maintenance Inspector, who

may add comments and then send it to the

Manager, ECO.

Note 2: Information concerning the

existence of approved alternative methods of

compliance with this airworthiness directive,

if any, may be obtained from the ECO.

Ferry Flights

(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 inspection requirements

of this AD can be accomplished.

Incorporation by Reference

(d) The actions required by this AD shall

be done in accordance with the following

CFE ASB:

Document No. Revision Pages Date

CFE738–A72–8031 .......................................................................................................................................... 1 ............. 1 June 23, 1999.

Original .. 2–5 May 17, 1999.

Total pages: 5.

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 CFE Company, Data Distribution, MS

64–03/2101–201, P.O. , PO Box 29003

Phoenix, AZ 85038–9003; telephone (602)

365–2493, fax (602) 365–5577. Copies may be

inspected at the FAA, New England Region,

Office of the Regional Counsel, 12 New

England Executive Park, Burlington, MA; or

at the Office of the Federal Register, 800

North Capitol Street, NW, suite 700,

Washington, DC.

(e) This amendment becomes effective on

February 10, 2000.

Issued in Burlington, Massachusetts, on

December 29, 1999.

Jay J. Pardee,

Manager, Engine and Propeller Directorate,

Aircraft Certification Service.

[FR Doc. 00–133 Filed 1–5–00; 8:45 am]

BILLING CODE 4910–13–U

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 99–NE–62–AD; Amendment 39–

11496; AD 99–27–15]

RIN 2120–AA64

Airworthiness Directives; General

Electric Company GE90 Series

Turbofan Engines

AGENCY: Federal Aviation

Administration, DOT.

ACTION: Final rule; request for

comments.

SUMMARY: This amendment adopts a

new airworthiness directive (AD) that is

applicable to certain General Electric

Company GE90 series turbofan engines.

This action requires visually inspecting

Ps3 and P3B sense lines and full

authority digital engine control (FADEC)

Ps3 and P3B sensing ports and fittings,

cleaning Ps3 and P3B fittings and

sensing ports, purging the Ps3 and P3B

systems of moisture, and, if necessary,

blending of high metal, nicks, burrs, or

scratches on Ps3 and P3B fitting threads.

This amendment is prompted by seven

reports of loss of thrust control due to

corruption of the signals to the FADEC

caused by water freezing in the Ps3

sensing system. The actions specified in

this AD are intended to prevent loss of

thrust control due to corruption of the

Ps3 and P3B signals to the FADEC

which if it occurs in a critical phase of

flight, could result in loss of aircraft

control.

DATES: Effective January 11, 2000.

The incorporation by reference of

certain publications listed in the

regulations is approved by the Director

of the Federal Register as of January 11,

2000.

Comments for inclusion in the Rules

Docket must be received on or before

March 6, 2000.

ADDRESSES: Submit comments to the

Federal Aviation Administration (FAA),

New England Region, Office of the

Regional Counsel, Attention: Rules

Docket No. 99–NE–62–AD, 12 New

England Executive Park, Burlington, MA

Federal Register / Vol. 65, No. 4 / Thursday, January 6, 2000 / Rules and Regulations 693

01803–5299. Comments may also be

sent via the Internet using the following

address: ‘‘9-ane-adcomment@faa.gov’’.

Comments sent via the Internet must

contain the docket number in the

subject line.

The service information referenced in

this AD may be obtained from General

Electric Company via Lockheed Martin

Technology Services, 10525 Chester

Road, Suite C, Cincinnati, OH 45215;

telephone 513–672–8400, fax 513–672–

8422. This information may be

examined at the FAA, New England

Region, Office of the Regional Counsel,

12 New England Executive Park,

Burlington, MA; or at the Office of the

Federal Register, 800 North Capitol

Street, NW, suite 700, Washington, DC.

FOR FURTHER INFORMATION CONTACT: John

E. Golinski, Aerospace Engineer, Engine

Certification Office, FAA, Engine and

Propeller Directorate, 12 New England

Executive Park, Burlington, MA 01803–

5299; telephone 781–238–7135, fax

781–238–7199.

SUPPLEMENTARY INFORMATION: The

Federal Aviation Administration (FAA)

has received seven reports of loss of

thrust control (LOTC) on General

Electric Company (GE) Model GE90

turbofan engines installed on Boeing

777 series aircraft. Five LOTC events

occurred in-flight and two occurred on

the ground. The five in-flight LOTC

events were temporary in that the

engine recovered and continued to

operate normally for the remainder of

the flight.

Investigation

The investigation revealed that water

can accumulate in the Ps3 and P3B

pressure sensing system, which can

freeze in the full authority digital engine

control (FADEC) sensing ports or

pressure line. Frozen water can result in

a restriction or a blocked signal to the

FADEC. This blocked signal can cause

a corruption of the FADEC signal and

result in abnormal engine start

characteristics on the ground or lack of

engine response to commanded thrust

levels in flight. Although there have

been no LOTC events attributed to icing

of the P3B sensing system in the field,

inspections have identified moisture in

this system, which could freeze and

corrupt the P3B signal to the FADEC as

well. This condition, if not corrected,

could result in LOTC due to blockage of

the FADEC sense lines, which if it

occurs in a critical phase of flight, could

result in loss of aircraft control.

Simultaneous LOTC Events

The FAA is especially concerned

about the possibility of simultaneous

LOTC events on both engines installed

on the Boeing 777 series aircraft due to

common mode threats, such as certain

atmospheric conditions that may result

in ice in the Ps3 or P3B pressure sensing

system and causing corrupted signals to

the FADEC in both engines.

Interim Action

Both Ps3 and P3B pressure systems

incorporate weep holes that allows

drainage of water in the lines that may

accumulate from condensation or

ingested water; however, the field

events and the investigation have

determined that these design features

may not always be effective in

eliminating water from these systems.

GE is assessing design changes that will

prevent water from freezing in these

systems and causing corruption of the

signals to the FADEC. The requirements

of this AD may change based on the

ongoing investigation of the root cause

and field inspection results, and future

rulemaking may be necessary.

Service Information

The FAA has reviewed and approved

the technical contents of GE Alert

Service Bulletin (ASB) GE90 73–A0060,

dated December 23, 1999, that describes

procedures for visually inspecting Ps3

and P3B sense lines and FADEC sensing

ports and fittings, cleaning Ps3 and P3B

fittings and sensor ports, purging the

Ps3 and P3B systems of moisture, and,

if necessary, blending of high metal,

nicks, burrs, or scratches on Ps3 and

P3B fitting threads.

Difference between ASB and AD

This AD contains provisions for

initial actions, and the ASB assumes

that all operators have completed the

initial actions based on field reports. If,

however, operators have already

accomplished the required initial

actions, they need not repeat those

actions, but may proceed directly to

accomplishing the repetitive actions.

Required Actions

Since an unsafe condition has been

identified that is likely to exist or

develop on other engines of the same

type design, this airworthiness directive

(AD) is being issued to prevent engine

LOTC events. This AD requires:

• Visual inspections for high metal,

nicks, burrs, or scratches on Ps3 and

P3B fitting threads, and, if necessary,

blending.

• Visual inspections for moisture,

debris, or ice in Ps3 and P3B FADEC

fittings, ports, and open sense lines.

• Cleaning of Ps3 and P3B FADEC

fittings and sensing ports.

• Purging of any moisture from the

Ps3 and P3B sense system.

• Engine idle leak check run

following the maintenance activity to

confirm no Ps3 or P3B sense system

faults are present.

Compliance Times

One of the GE90 series engines

installed on the Boeing 777 series

airplane must have the initial

inspection, cleaning, moisture purging,

and, if necessary, blending of high

metal, nicks, burrs, or scratches on Ps3

and P3B fitting threads, within 10

cycles-in-service (CIS) after the effective

date of this AD. The other engine

installed on the airplane must have the

initial inspection, cleaning, moisture

purging, and, if necessary, blending of

high metal, nicks, burrs, or scratches, on

Ps3 and P3B fitting threads, within 20

CIS after the effective date of this AD.

Based on concerns over concurrent

engine maintenance, engines installed

on the same Boeing 777 series airplane

must not have the inspection, cleaning,

moisture purging and, if necessary,

blending of high metal, nicks, burrs, or

scratches on Ps3 and P3B fitting threads

performed concurrently.

Credit for Previous Inspections,

Cleaning, and Moisture Purging

Engines that have been inspected,

cleaned, and moisture purged in

accordance with GE90 All Reps Wire,

JSB99–11–24–1, Revision 1, dated

November 25, 1999, may count those

inspections, cleaning, and moisture

purging as accomplished and must be

inspected, cleaned, moisture purged,

and, if necessary, have high metal,

nicks, burrs, or scratches on Ps3 and

P3B fitting threads blended, within 30

CIS since those last actions. Engines that

have accumulated 30 CIS or greater

since previous inspection, cleaning, and

moisture purging on the effective date of

the AD must repeat the required

procedures within 5 CIS after the

effective date of this AD. Engines that

have accumulated less than 30 CIS since

previous inspection, cleaning, and

moisture purging on the effective date of

this AD must repeat the required

procedures within 30 CIS since last

inspection, or within 5 CIS after the

effective date of this AD, whichever

occurs later.

Repetitive Actions

Thereafter, operators must inspect,

clean, moisture purge, and, if necessary,

blend high metal, nicks, burrs, or

scratches on Ps3 and P3B fitting threads

at intervals not to exceed 30 CIS since

last inspection.

694 Federal Register / Vol. 65, No. 4 / Thursday, January 6, 2000 / Rules and Regulations

Immediate Adoption

Since a situation exists that requires

the immediate adoption of this

regulation, it is found that notice and

opportunity for prior public comment

hereon are impracticable, and that good

cause exists for making this amendment

effective in less than 30 days.

Comments Invited

Although this action is in the form of

a final rule that involves requirements

affecting flight safety and, thus, was not

preceded by notice and an opportunity

for public comment, comments are

invited on this rule. Interested persons

are invited to comment on this rule by

submitting such written data, views, or

arguments as they may desire.

Communications should identify the

Rules Docket number and be submitted

to the address specified under the

caption ADDRESSES. All communications

received on or before the closing date

for comments will be considered, and

this rule may be amended in light of the

comments received. Factual information

that supports the commenter’s ideas and

suggestions is extremely helpful in

evaluating the effectiveness of the AD

action and determining whether

additional rulemaking action would be

needed.

Comments are specifically invited on

the overall regulatory, economic,

environmental, and energy aspects of

the rule that might suggest a need to

modify the rule. All comments

submitted will be available, both before

and after the closing date for comments,

in the Rules Docket for examination by

interested persons. A report that

summarizes each FAA-public contact

concerned with the substance of this AD

will be filed in the Rules Docket.

Commenters wishing the FAA to

acknowledge receipt of their comments

submitted in response to this notice

must submit a self-addressed, stamped

postcard on which the following

statement is made: ‘‘Comments to

Docket Number 99–NE–62–AD.’’ The

postcard will be date stamped and

returned to the commenter.

Regulatory Impact

The regulations adopted herein will

not have a substantial direct effect 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, it is

determined that this final rule does not

have federalism implications under

Executive Order (EO) 13132.

The FAA has determined that this

regulation is an emergency regulation

that must be issued immediately to

correct an unsafe condition in aircraft,

and is not a ‘‘significant regulatory

action’’ under EO 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:

99–27–15 General Electric Company:

Amendment 39–11496. Docket 99–NE–

62–AD.

Applicability: General Electric Company

(GE) Models GE90–76B, –77B, –85B, –90B,

and –92B turbofan engines, installed on but

not limited to Boeing 777 series airplanes.

Note 1: This airworthiness directive (AD)

applies to each engine 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 engines that

have been modified, altered, or repaired so

that the performance of the requirements of

this AD is affected, the owner/operator must

request approval for an alternative method of

compliance in accordance with paragraph (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.

To prevent loss of thrust control due to

corruption of the Ps3 and P3B signals to the

full authority digital engine control (FADEC),

which if it occurs in a critical phase of flight,

could result in loss of aircraft control,

accomplish the following:

Initial Inspection, Cleaning, Moisture

Purging, and Blending

(a) Perform the following initial actions in

accordance with the Accomplishment

Instructions, Section (3) of GE Alert Service

Bulletin (ASB) No. 73–A0060, dated

December 23, 1999:

(1) Inspect, clean, moisture purge, and if

necessary, blend any high metal, nicks, or

burrs on fitting threads, on one engine

installed on Boeing 777 series aircraft, within

10 cycles-in-service (CIS) after the effective

date of this AD.

(2) Inspect, clean, moisture purge, and if

necessary, blend any high metal, nicks, or

burrs on fitting threads, on the other engine

installed on the Boeing 777 series aircraft,

within 20 CIS after the effective date of this

AD.

Credit for Previous Inspections, Cleaning,

and Moisture Purging

(b) Engines that have been inspected,

cleaned, and moisture purged in accordance

with GE90 All Reps Wire, JSB99–11–24–1,

Revision 1, dated November 25, 1999, may

count those inspections, cleaning, and

moisture purging as accomplished and must

be inspected, cleaned, moisture purged, and

if necessary, have any high metal, nicks, or

burrs on fitting threads blended, in

accordance with the Accomplishment

Instructions, Section (3) of GE ASB No. 73–

A0060, dated December 23, 1999, and the

following schedule:

(1) Engines that have accumulated 30 CIS

or greater since previous inspection,

cleaning, and moisture purging on the

effective date of the AD must repeat the

required procedures within 5 CIS after the

effective date of this AD.

(2) Engines that have accumulated less

than 30 CIS since previous inspection,

cleaning, and moisture purging on the

effective date of this AD must repeat the

required procedures within 30 CIS since last

inspection, or within 5 CIS after the effective

date of this AD, whichever occurs later.

New and Replacement Engines

(c) For new and replacement engines,

perform the initial inspection, cleaning, and

moisture purging, and if necessary, blend any

high metal, nicks, or burrs on fitting threads,

prior to accumulating 30 CIS since entering

service in accordance with the

Accomplishment Instructions, Section (3) of

GE ASB No. 73–A0060, dated December 23,

1999.

Repetitive Inspections

(d) Thereafter, inspect, clean, and moisture

purge, and if necessary, blend any high

metal, nicks, or burrs on fitting threads each

engine within 30 CIS since last inspection, in

accordance with the Accomplishment

Instructions, Section (3) of GE ASB No. 73–

A0060, dated December 23, 1999.

Idle Leak Check

(e) After accomplishing the required

actions of this AD, and prior to entry into

Federal Register / Vol. 65, No. 4 / Thursday, January 6, 2000 / Rules and Regulations 695

service, perform an idle leak check to

confirm no Ps3 or P3B sense system faults in

accordance with the Accomplishment

Instructions, Section (3), paragraph (14), of

GE ASB No. 73–A0060, dated December 23,

1999.

No Simultaneous Actions

(f) Do not perform the actions required by

this AD concurrently on both engines

installed on a Boeing 777 series aircraft.

Alternative Methods of Compliance

(g) 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, Engine

Certification Office (ECO). Operators shall

submit their requests through an appropriate

FAA Principal Maintenance Inspector, who

may add comments and then send it to the

Manager, ECO.

Note 2: Information concerning the

existence of approved alternative methods of

compliance with this airworthiness directive,

if any, may be obtained from the ECO.

Ferry Flights

(h) 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 aircraft to

a location where the requirements of this AD

can be accomplished.

Incorporation by Reference

(i) The actions required by this AD shall be

done in accordance with GE ASB No. 73–

A0060, dated December 23, 1999. 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 General

Electric Company via Lockheed Martin

Technology Services, 10525 Chester Road,

Suite C, Cincinnati, OH 45215; telephone

513–672–8400, fax 513–672–8422. Copies

may be inspected at the FAA, New England

Region, Office of the Regional Counsel, 12

New England Executive Park, Burlington,

MA; or at the Office of the Federal Register,

800 North Capitol Street, NW, suite 700,

Washington, DC.

(j) This amendment becomes effective on

January 11, 2000.

Issued in Burlington, Massachusetts, on

December 29, 1999.

Jay J. Pardee,

Manager, Engine and Propeller Directorate,

Aircraft Certification Service.

[FR Doc. 00–134 Filed 1–5–00; 8:45 am]

BILLING CODE 4910–13–U

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 99–NM–236–AD; Amendment

39–11494; AD 99–27–13]

RIN 2120–AA64

Airworthiness Directives; Fokker

Model F27 Mark 050 Series Airplanes

AGENCY: Federal Aviation

Administration, DOT.

ACTION: Final rule; request for

comments.

SUMMARY: This amendment adopts a

new airworthiness directive (AD),

applicable to all Fokker Model F27

Mark 050 series airplanes. This action

requires using a torque wrench to

repetitively tighten the screws for the

attachment of the leading edges of the

elevators, rudder, and ailerons. This

amendment is prompted by issuance of

mandatory continuing airworthiness

information by a foreign civil

airworthiness authority. The actions

specified in this AD are intended to

prevent loose attachment screws on the

leading edges of the elevators, rudder,

and ailerons due to vibration, which

could result in interference with

adjacent structure and consequent

reduced controllability of the airplane.

DATES: Effective January 21, 2000.

The incorporation by reference of

certain publications listed in the

regulations is approved by the Director

of the Federal Register as of January 21,

2000.

Comments for inclusion in the Rules

Docket must be received on or before

February 7, 2000.

ADDRESSES: Submit comments in

triplicate to the Federal Aviation

Administration (FAA), Transport

Airplane Directorate, ANM–114,

Attention: Rules Docket No. 99–NM–

236–AD, 1601 Lind Avenue, SW.,

Renton, Washington 98055–4056.

The service information referenced in

this AD may be obtained from Fokker

Services B.V., P.O. Box 231, 2150 AE

Nieuw-Vennep, The Netherlands. 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:

Norman B. Martenson, Manager,

International Branch, ANM–116, FAA,

Transport Airplane Directorate, 1601

Lind Avenue, SW., Renton, Washington

98055–4056; telephone (425) 227–2110;

fax (425) 227–1149.

SUPPLEMENTARY INFORMATION: The

Rijksluchtvaartdienst (RLD), which is

the airworthiness authority for the

Netherlands, notified the FAA that an

unsafe condition may exist on all

Fokker Model F27 Mark 050 series

airplanes. The RLD advises that, after an

airplane landed, the elevator control

was found binding in the fully ‘‘UP’’

position. Subsequent investigation of

the elevator revealed that an attachment

screw had come loose and moved out of

the elevator leading edge section against

the horizontal stabilizer. The leading

edges of the elevators are attached by

screws in anchor nuts on the elevator

front spar. The screws are thought to

have come loose due to vibration. The

subject screws on the leading edge of

the rudder and ailerons are identical to

those on the affected elevators.

Loose attachment screws on the

leading edges of the elevators, rudder, or

ailerons, if not corrected, could result in

interference of the leading edges with

adjacent structure and consequent

reduced controllability of the airplane.

Explanation of Relevant Service

Information

Fokker has issued Service Bulletin

SBF50–55–007, dated June 5, 1998,

which describes procedures for using a

torque wrench to repetitively tighten the

screws for the attachment of the leading

edges of the elevator.

Fokker also has issued Service

Bulletin SBF50–57–020, Revision 1,

dated July 23, 1999, which describes

procedures for using a torque wrench to

repetitively tighten the screws for the

attachment of the leading edges of the

aileron.

In addition, Fokker has issued Service

Bulletin SBF50–55–009, Revision 1,

dated July 23, 1999, which describes

procedures for using a torque wrench to

repetitively tighten the screws for the

attachment of the leading edges of the

rudder.

The RLD classified these service

bulletins as mandatory and issued

Dutch airworthiness directive 1998–

070/3, dated August 31, 1999, in order

to assure the continued airworthiness of

these airplanes in the Netherlands.

FAA’s Conclusions

These airplane models are

manufactured in the Netherlands and

are type certificated for operation in the

United States under the provisions of

section 21.29 of the Federal Aviation

Regulations (14 CFR 21.19) and the

applicable bilateral airworthiness

agreement. Pursuant to this bilateral