This section of the FEDERAL REGISTER

contains regulatory documents having general

applicability and legal effect, most of which

are keyed to and codified in the Code of

Federal Regulations, which is published under

50 titles pursuant to 44 U.S.C. 1510.

The Code of Federal Regulations is sold by

the Superintendent of Documents. Prices of

new books are listed in the first FEDERAL

REGISTER issue of each week.

Rules and Regulations Federal Register

52653

Vol. 62, No. 196

Thursday, October 9, 1997

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 97–SW–24–AD; Amendment

39–10152; AD 97–15–16]

RIN 2120–AA64

Airworthiness Directives; Bell

Helicopter Textron Canada (BHTC)

Model 430 Helicopters

AGENCY: Federal Aviation

Administration, DOT.

ACTION: Final rule; request for

comments.

SUMMARY: This document publishes in

the Federal Register an amendment

adopting Airworthiness Directive (AD)

97–15–16, which was sent previously to

all known U.S. owners and operators of

BHTC Model 430 helicopters by

individual letters. This AD requires

inspections of all 4 main rotor adapter

assemblies for evidence of flapping

contact between the adapter liners and

the upper stop assembly plugs, and for

evidence of lead-lag contact between the

adapter pads and the yoke assembly;

installing a never-exceed-velocity (VNE)

placard; marking the airspeed indicator

to reflect the airspeed restriction;

installing a slippage mark on the

airspeed indicator glass and instrument

case; and inserting revisions to the

rotorcraft flight manual to reflect the

airspeed revision. This amendment is

prompted by a report of a main rotor tip

path plane separation, which occurred

during a ferry flight at an airspeed of

more than 140 knots indicated airspeed

(KIAS). The actions specified by this AD

are intended to prevent tip path plane

separation, increased vibrations,

possible damage to the main rotor

system, and subsequent loss of control

of the helicopter.

DATES: Effective October 24, 1997, to all

persons except those persons to whom

it was made immediately effective by

priority letter AD 97–15–16, issued on

July 18, 1997, which contained the

requirements of this amendment.

The incorporation by reference of

certain publications listed in the

regulations is approved by the Director

of the Federal Register as of October 24,

1997.

Comments for inclusion in the Rules

Docket must be received on or before

December 8, 1997.

ADDRESSES: Submit comments in

triplicate to the Federal Aviation

Administration (FAA), Office of the

Assistant Chief Counsel, Attention:

Rules Docket No. 97–SW–24–AD, 2601

Meacham Blvd., Room 663, Fort Worth,

Texas 76137.

The applicable service information

may be obtained from Bell Helicopter

Textron Canada, 12,800 Rue de l’Avenir,

Mirabel, Quebec JON1LO, telephone

(800) 463–3036, fax (514) 433–0272.

This information may be examined at

the FAA, Office of the Assistant Chief

Counsel, 2601 Meacham Blvd., Room

663, Fort Worth, Texas; or at the Office

of the Federal Register, 800 North

Capitol Street, NW., suite 700,

Washington, DC.

FOR FURTHER INFORMATION CONTACT: Mr.

Harry Edmiston, Aerospace Engineer,

Rotorcraft Certification Office,

Rotorcraft Directorate, FAA, 2601

Meacham Blvd., Fort Worth, Texas

76137, telephone (817) 222–5158, fax

(817) 222–5783.

SUPPLEMENTARY INFORMATION: On July

18, 1997, the FAA issued priority letter

AD 97–15–16, applicable to BHTC

Model 430 helicopters, which requires

inspections of all 4 main rotor adapter

assemblies for evidence of flapping

contact between the adapter liners and

the upper stop assembly plugs, and for

evidence of lead-lag contact between the

adapter pads and the yoke assembly;

installing a VNE placard; marking the

airspeed indicator to reflect the airspeed

restriction; installing a slippage mark on

the airspeed indicator glass and

instrument case; and inserting revisions

to the rotorcraft flight manual to reflect

the airspeed revision. That action was

prompted by one report of a main rotor

tip path plane separation, which

occurred during a ferry flight at an

airspeed of more than 140 KIAS. The

separation was observed from the

cockpit and caused a vibration at a

frequency near one per revolution.

BHTC was able to reproduce a similar

event on other Model 430 helicopters,

and determined that the separation may

occur at airspeeds above 120 KIAS.

Therefore, flight at airspeeds above 120

KIAS is considered unsafe. This

condition, if not corrected, could result

in tip path plane separation, increased

vibrations, possible damage to the main

rotor system, and subsequent loss of

control of the helicopter.

The FAA has reviewed Bell

Helicopter Textron Alert Service

Bulletin (ASB) No. 430–97–2, dated July

11, 1997, which describes inspections of

all 4 main rotor adapter assemblies for

evidence of flapping contact between

the adapter liners and the upper stop

assembly plugs; and, for evidence of

lead-lag contact between the adapter

pads and the yoke assembly. The ASB

also describes further inspections if

evidence of contact is found during

either of those inspections. For

helicopters equipped with skid landing

gear, removing the existing VNE placard

and installing a VNE placard, part

number (P/N) 430–075–208–107, is

required; and for helicopters equipped

with retractable landing gear, removing

the existing VNE placard and installing

a VNE placard, P/N 430–075–208–109,

is required. Finally, the ASB describes

marking the airspeed indicators to

reflect the airspeed restriction by adding

to the instrument glass a red arc to

indicate that airspeeds above 120 KIAS

are prohibited; and inserting revisions

to the rotorcraft flight manual that

reflect this airspeed restriction.

Since the unsafe condition described

is likely to exist or develop on other

BHTC Model 430 helicopters of the

same type design, the FAA issued

priority letter AD 97–15–16 to prevent

tip path plane separation, increased

vibrations, possible damage to the main

rotor system, and subsequent loss of

control of the helicopter. The AD

requires, before further flight,

inspections of all 4 main rotor adapter

assemblies for evidence of flapping

contact between the adapter liners and

the upper stop assembly plugs, and for

evidence of lead-lag contact between the

adapter pads and the yoke assembly.

Flapping contact is indicated by

scrubbing (or smudging) of the adapter

liner surface, characteristic of relative

motion between the surfaces of the

adapter liners and upper stop assembly

plugs. Lead-lag contact is indicated by
52654 Federal Register / Vol. 62, No. 196 / Thursday, October 9, 1997 / Rules and Regulations

a permanent indentation or split in the

surface of the adapter pads. Further

inspections are required if evidence of

contact is found during either of those

inspections. For helicopters equipped

with skid landing gear, this AD requires

the removing the existing VNE placard

and installing a VNE placard, P/N 430–

075–208–107; and for helicopters

equipped with retractable landing gear,

removing the existing VNE placard and

installing a VNE placard, P/N 430–075–

208–109, is required. Finally, this AD

requires marking each airspeed

indicator to reflect the airspeed

restriction by adding to the instrument

glass a red arc to indicate that airspeeds

above 120 KIAS are prohibited;

installing a slippage mark on each

airspeed indicator glass and instrument

case; and inserting revisions to the

rotorcraft flight manual that reflect the

airspeed restriction. The actions are

required to be accomplished in

accordance with the service bulletin

described previously.

Since it was found that immediate

corrective action was required, notice

and opportunity for prior public

comment thereon were impracticable

and contrary to the public interest, and

good cause existed to make the AD

effective immediately by individual

letters issued on July 18, 1997 to all

known U.S. owners and operators of

BHTC Model 430 helicopters. These

conditions still exist, and the AD is

hereby published in the Federal

Register as an amendment to § 39.13 of

the Federal Aviation Regulations (14

CFR 39.13) to make it effective to all

persons.

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

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

concernedwith 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 No. 97–SW–24–AD.’’ The

postcard will be date stamped and

returned to the commenter.

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 a new airworthiness directive to

read as follows:

97–15–16 Bell Helicopter Textron Canada:

Amendment 39–10152. Docket No. 97–

SW–24–AD.

Applicability: Model 430 helicopters,

certificated in any category.

Note 1: This AD applies to each helicopter

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

helicopters that have been modified, altered,

or repaired so that the performance of the

requirements of this AD is affected, the

owner/operator must use the authority

provided in paragraph (g) to request approval

from the FAA. This approval may address

either no action, if the current configuration

eliminates the unsafe condition, or different

actions necessary to address the unsafe

condition described in this AD. Such a

request should include an assessment of the

effect of the changed configuration on the

unsafe condition addressed by this AD. In no

case does the presence of any modification,

alteration, or repair remove any helicopter

from the applicability of this AD.

Compliance: Required before further flight,

unless accomplished previously.

To prevent tip path plane separation,

increased vibrations, possible damage to the

main rotor system, and subsequent loss of

control of the helicopter, accomplish the

following:

(a) Inspect all 4 main rotor adapter

assemblies for evidence of flapping contact

between the adapter liners and the upper

stop assembly plugs. Refer to Figures 1, 2,

and 3 of the Accomplishment Instructions of

Bell Helicopter

Textron Canada (BHTC) Alert Service

Bulletin (ASB) No. 430–97–2, dated July 11,

1997. Flapping contact is indicated by

scrubbing (or smudging) of the adapter liner

surface, characteristic of relative motion

between the surfaces of the adapter lines and

upper stop assembly plugs.

(b) Inspect all 4 main rotor adapter

assemblies for evidence of lead-lag contact

between the adapter pads and the yoke

assembly. Refer to Figures 1 and 2 of the

Accomplishment Instructions of BHTC ASB

No. 430–97–2, dated July 11, 1997. Lead-lag

contact is indicated by a permanent

indentation or split in the surface of the

adapter pads.

(c) If the inspections in paragraphs (a) or

(b) of this AD reveal that there has been

contact, inspect and replace the main rotor

yoke and stop assemblies in accordance with

Part I, No. 3 of the Accomplishment

Instructions of BHTC ASB No. 430–97–2,

dated July 11, 1997.

(d) For helicopters equipped with skid

landing gear or retractable landing gear,
Federal Register / Vol. 62, No. 196 / Thursday, October 9, 1997 / Rules and Regulations 52655

remove the existing never-exceed-velocity

(VNE) placard from the overhead console and

install VNE placard, P/N 430–075–208–107,

or P/N 430–075–208–109, as applicable, in

accordance with Part II, of the

Accomplishment Instructions of BHTC ASB

No. 430–97–2, dated July 11, 1997.

(e) Install on each airspeed indicator a red

arc between 120 knots and 150 knots to

indicate that airspeeds above 120 knots

indicated airspeed are prohibited. Install a

slippage mark on each airspeed indicator

glass and instrument case.

(f) Insert the temporary revisions, BHT–

430–FM–1 and BHT–430–FMS–1, as

appropriate, both dated July 7, 1997, into the

rotorcraft flight manual.

(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, Rotorcraft

Certification Office, Rotorcraft Directorate,

FAA. Operators shall submit their requests

through an FAA Principal Maintenance

Inspector, who may concur or comment and

then send it to the Manager, Rotorcraft

Certification Office.

Note 2: Information concerning the

existence of approved alternative methods of

compliance with this AD, if any, may be

obtained from the Rotorcraft Certification

Office.

(h) Special flight permits will not be

issued.

(i) The inspections and installations shall

be done in accordance with Bell Helicopter

Textron Alert Service Bulletin (ASB) No.

430–97–2, dated July 11, 1997. This

incorporation by reference was approved by

the Director of the Federal Register in

accordance with 5 U.S.C. 552(a) and 1 CFR

part 51. Copies may be obtained from Bell

Helicopter Textron Canada, 12,800 Rue de

l’Avenir, Mirabel, Quebec JON1LO,

telephone (800) 463–3036, fax (514) 433–

0272. Copies may be inspected at the FAA,

Office of the Assistant Chief Counsel, 2601

Meacham Blvd., Room 663, Fort Worth,

Texas; or at the Office of the Federal Register,

800 North Capitol Street, NW., suite 700,

Washington, DC.

(j) This amendment becomes effective on

October 24, 1997, to all persons except those

persons to whom it was made immediately

effective by priority letter AD 97–15–16,

issued July 18, 1997, which contained the

requirements of this amendment.

Issued in Fort Worth, Texas, on September

26, 1997.

Eric Bries,

Acting Manager, Rotorcraft Directorate,

Aircraft Certification Service.

[FR Doc. 97–26623 Filed 10–8–97; 8:45 am]

BILLING CODE 4910–13–U

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 97–SW–15–AD; Amendment

39–10153; AD 97–20–16]

RIN 2120–AA64

Airworthiness Directives; Eurocopter

Deutschland GmbH (ECD) (Eurocopter)

Model MBB–BK117 A–1, A–3, A–4, B–

1, B–2, and C–1 Helicopters

AGENCY: Federal Aviation

Administration, DOT.

ACTION: Final rule; request for

comments.

SUMMARY: This amendment supersedes

an existing airworthiness directive (AD),

applicable to Eurocopter Model MBB–

BK117 A–1, A–3, A–4, B–1, B–2, and C–

1 helicopters, that currently requires

initial and repetitive inspections of both

surfaces of the tail boom vertical fin

(vertical fin) spar, the skin, and the lefthand and right-hand frame sheets for

cracks or loose rivets. This amendment

requires the same initial and repetitive

inspections of the vertical fin spar that

are required by the existing AD, and

also requires repairing certain cracks, if

found, and repairing and reporting loose

rivets and certain other cracks, if found.

This amendment is prompted by an

accident which occurred on April 15,

1997, resulting in one fatality. A

subsequent investigation revealed that

the vertical fin had failed as a result of

a fatigue crack that initiated on the left

side of the vertical fin spar cap. The

actions specified by this AD are

intended to prevent failure of the

vertical fin and subsequent loss of

control of the helicopter.

DATES: Effective October 24, 1997. The

incorporation by reference of certain

publications listed in the regulations is

approved by the Director of the Federal

Register as of October 24, 1997.

Comments for inclusion in the Rules

Docket must be received on or before

December 8, 1997.

ADDRESSES: Submit comments in

triplicate to the Federal Aviation

Administration (FAA), Office of

Regional Counsel, Southwest Region,

Attention: Rules Docket No. 97–SW–15–

AD, 2601 Meacham Blvd., Room 663,

Fort Worth, Texas 76137.

The service information referenced in

this AD may be obtained from American

Eurocopter Corporation, 2701 Forum

Drive, Grand Prairie, Texas 75053–4005,

telephone (972) 641–3460, fax (972)

641–3527. This information may be

examined at the FAA, Office of Regional

Counsel, Southwest Region, 2601

Meacham Blvd., Room 663, Fort Worth,

Texas 76137; or at the Office of the

Federal Register, 800 North Capitol

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

FOR FURTHER INFORMATION CONTACT:

Mr. Richard Monschke, Aerospace

Engineer, Rotorcraft Standards Staff,

2601 Meacham Blvd., Fort Worth, Texas

76137, telephone (817) 222–5116, fax

(817) 222–5961.

SUPPLEMENTARY INFORMATION: On April

25, 1997, the FAA issued priority letter

AD 97–09–16, to require inspecting both

surfaces of the vertical fin spar, part

number (P/N) 105–304061.03, P/N

1120–30406.03, or P/N 117–30423–03,

paying particular attention to the area

extending from the top edge of the

second lightening hole from the top of

the vertical fin spar to the bottom edge

of the fourth lightening hole, the outer

skin (skin), and the left-hand and righthand frame plates for cracks, loose

rivets, or other anomalies. This

inspection must be performed before

further flight, then repeated at intervals

not to exceed 100 hours time-in-service.

That action was prompted by an

accident involving a Eurocopter Model

MBB–BK117 series helicopter, which

occurred on April 15, 1997, resulting in

one fatality. A subsequent investigation

revealed that the vertical fin had failed

as a result of a fatigue crack that

initiated on the left side of the vertical

fin spar cap. The crack propagated

across the spar cap and spar web until

only the skin was carrying the flight

load. The skin then started cracking,

with the crack propagating horizontally

toward the vertical fin leading edge

until catastrophic overstress occurred.

Inspections of other helicopters of the

same type design revealed cracks in the

vertical fin spars of three additional

helicopters. That condition, if not

corrected, could result in failure of the

vertical fin and subsequent loss of

control of the helicopter.

Since the issuance of that AD, the

manufacturer has developed repair

procedures for the cracks, which were

unavailable at the time of the release of

the priority letter AD, and has issued

Eurocopter Alert Service Bulletin MBB–

BK117 No. ASB–MBB–BK117–30–106,

Revision 3, dated May 5, 1997, which

specifies repair procedures for the spar

cap, as well as subsequent inspection

requirements.

This helicopter model is

manufactured in The Federal Republic

of Germany 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