1864 Federal Register / Vol. 62, No. 9 / Tuesday, January 14, 1997 / Proposed Rules

14 CFR Part 39

[Docket No. 94–SW–26–AD]

Airworthiness Directives; Bell

Helicopter Textron, Inc. Model 214B,

214B–1, and 214ST Helicopters

AGENCY: Federal Aviation

Administration, DOT.

ACTION: Notice of proposed rulemaking

(NPRM).

SUMMARY: This document proposes the

supersedure of an existing airworthiness

directive (AD), applicable to Bell

Helicopter Textron, Inc. (BHTI) Model

214B, 214B–1, and 214ST helicopters,

that currently establishes a mandatory

retirement life of 60,000 high-power

events for the main transmission upper

planetary carrier (carrier). This action

would require changing the method of

calculating retirement life for the carrier

from high-power events to a maximum

accumulated Retirement Index Number

(RIN) of 120,000. This proposal is

prompted by fatigue analyses and tests

that show certain carriers fail sooner

than originally anticipated because of

the unanticipated high number of lifts

or takeoffs (torque events) performed

with those carriers in addition to the

time-in-service (TIS) accrued under

other operating conditions. The actions

specified by the proposed AD are

intended to prevent fatigue failure of the

carrier, which could result in failure of

the main transmission and subsequent

loss of control of the helicopter.

DATES: Comments must be received by

March 17, 1997.

ADDRESSES: Submit comments in

triplicate to the Federal Aviation

Administration (FAA), Office of the

Assistant Chief Counsel, Attention:

Rules Docket No. 94–SW–26–AD, 2601

Meacham Blvd., Room 663, Fort Worth,

Texas 76137. 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

Bell Helicopter Textron, Inc., P.O. Box

482, Fort Worth, Texas 76101.

FOR FURTHER INFORMATION CONTACT: Mr.

Uday Garadi, Aerospace Engineer, FAA,

Rotorcraft Directorate, Rotorcraft

Certification Office, Fort Worth, Texas

76193–0170, telephone (817) 222–5157,

fax (817) 222–5959.

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

should 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 No. 94–SW–26–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, Office of the Assistant Chief

Counsel, Attention: Rules Docket No.

94–SW–26–AD, 2601 Meacham Blvd.,

Room 663, Fort Worth, Texas 76137.

Discussion

On June 6, 1994, the FAA issued AD

94–02–05, Amendment 39–8803, (59 FR

32325, June 23, 1994), to require

changing the method of calculating the

retirement life for the carrier, part

number (P/N) 214–040–077–007 and

–101, from flight hours to high-power

events calculated using the number of

takeoffs and external load lifts,

removing the 2,500 hours TIS magnetic

particle inspection for the carrier, and

making the requirements applicable to

the Model 214ST as well as the Model

214B and 214B–1 helicopters. That

action was prompted by fatigue analyses

and tests that show certain carriers fail

sooner than originally anticipated

because of the unanticipated high

number of lifts and takeoffs (torque

events) performed with those carriers in

addition to the TIS accrued under other

operating conditions. The requirements

of that AD are intended to prevent

fatigue failure of the carrier, which

could result in failure of the main

transmission and subsequent loss of

control of the helicopter.

Since the issuance of that AD, BHTI

has issued BHTI Information Letter

GEN–94–54, dated April 15, 1994,

Subject: Retirement Index Number (RIN)

For Cycle Lifed Components, which

introduces a different method of

accounting for fatigue damage on

components that have shortened service

lives as a result of frequent torque

events. Additionally, BHTI has issued

BHTI Alert Service Bulletin (ASB) 214–

94–52, which is applicable to Model

214B helicopters, and ASB 214ST–94–

66, which is applicable to Model 214ST

helicopters, both of which are dated

November 7, 1994, and describe

procedures for converting flight hours

and total number of torque events into

a RIN for the carrier, P/N214–040–077–

007 and –101. Although ASB 214–94–52

does not state that it applies to Model

214B–1 helicopters, this was an

oversight by the manufacturer. That

ASB was intended to apply to both

Model 214B and 214B–1 helicopters.

Since an unsafe condition has been

identified that is likely to exist or

develop on other BHTI Model 214B,

214B–1, and 214ST helicopters of the

same type design, the proposed AD

would supersede AD 94–02–05 to

require creation of a component history

card using the RIN system and a system

for tracking increases to the

accumulated RIN, and establish a

maximum accumulated RIN for the

carrier of 120,000 at which it must be

retired.

The FAA estimates that 11 helicopters

of U.S. registry would be affected by this

proposed AD, that it would take

approximately (1) 48 work hours per

helicopter to replace the affected part

due to the new method of determining

the retirement life required by this AD;

(2) 2 work hours per helicopter to create

the component history card or

equivalent record (record); and (3) 10

work hours per helicopter to maintain

the record each year, and that the

average labor rate is $60 per work hour.

Required parts would cost

approximately $29,516 per helicopter.

Based on these figures, the total cost

impact of the proposed AD on U.S.

operators is estimated to be $61,813 for

the first year and $60,713 for each

subsequent year. These costs assume

replacement of the spider in one-sixth of

the fleet each year, creation and

maintenance of the records for all the

fleet the first year, and creation of onesixth of the fleet’s records and

maintenance of the records for all the

fleet each subsequent year.

The regulations proposed herein

would not have substantial direct effects

on the States, on the relationship

between the national government and
Federal Register / Vol. 62, No. 9 / Tuesday, January 14, 1997 / Proposed Rules 1865

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

removing Amendment 39–8803 (59 FR

32325, June 23, 1994), and by adding a

new airworthiness directive (AD), to

read as follows:

Bell Helicopter Textron, Inc. (BHTI): Docket

No. 94–SW–26–AD. Supersedes AD 94–

02–05, Amendment 39–8803.

Applicability: Model 214B, 214B–1, and

214ST helicopters with main transmission

upper planetary carrier (carrier), part number

(P/N) 214–040–077–007 or –101, installed,

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 (e) 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 within 25 hours

time-in-service (TIS) after the effective date

of this AD, unless accomplished previously.

To prevent fatigue failure of the carrier,

which could result in failure of the main

transmission and subsequent loss of control

of the helicopter, accomplish the following:

(a) Create a component history card or

equivalent record for the upper planetary

carrier (carrier), P/N 214–040–077–007 or

–101.

(b) Determine and record the accumulated

Retirement Index Number (RIN) to date on

the carrier as follows (if the multiplication

results in a fraction, round the results up to

the next whole number):

(1) For Model 214B or B–1 helicopters:

(i) Multiply the high-power event total to

date by 2, or

(ii) If the actual operating hours are known,

and:

(A) If the type of operation is internal load

lift operations only, multiply each operating

hour by 7;

(B) If the type of operation involves any

external load lift operations and the number

of external load lift operations is known, use

the table below and multiply the appropriate

factor for the average number of external load

lift operations by the number of actual

operating hours:

Average number of external load

lift operations per hour Factor*

0–2.00 ........................................... 7

2.01–5.00 ...................................... 7

5.01–16.00 .................................... 14

16.01–27.00 .................................. 21

Above 27.00 .................................. 28

* RIN = Factor × Actual Operating Hours.

(C) If the type of operation involves any

external load lift operations and the number

of external load lift operations is unknown,

multiply each actual operating hour by 21; or

(D) If the type of operation is unknown,

multiply each actual operating hour by 21.

(iii) If the actual operating hours are

unknown, assume 900 operating hours per

calendar year. Prorate the assumed operating

hours for partial years.

(A) If the type of operation is internal only,

multiply the assumed operating hours by 7.

(B) If the type of operation involves any

external load lift operations and the number

of external load lift operations is known, use

the table in paragraph (ii)(B) above and

multiply the appropriate factor for the

average number of external load lift

operations by the number of assumed

operating hours;

(C) If the type of operation involves any

external load lift operations and the number

of external load lift operations is unknown,

multiply each assumed operating hour by 21.

(D) If the type of operation is unknown,

multiply each assumed operating hour by 21.

(2) For Model 214ST helicopters:

(i) Multiply the high-power event total todate by 2, or

(ii) Multiply the factored flight hour total

to-date by 12.

Note 2: BHTI Alert Service Bulletin (ASB)

214–94–52, which is applicable to Model

214B helicopters, and ASB 214ST–94–66,

which is applicable to Model 214ST

helicopters, both of which are dated

November 7, 1994, pertain to this subject.

(c) After compliance with paragraphs (a)

and (b) of this AD, and during each operation

thereafter, maintain a count of each lift or

takeoff performed and at the end of each

day’s operations, increase the accumulated

RIN on the component history card or

equivalent record as follows:

(1) For Model 214B and 214B–1

helicopters,

(i) Increase the RIN by 1 for each takeoff.

(ii) Increase the RIN by 1 for each external

load lift operation; or, increase the RIN by 2

for each external load lift operation in which

the load is picked up at a higher elevation

and released at a lower elevation, and the

difference in the elevation between the pick

up point and the release point is 200 feet or

greater.

(2) For Model 214ST helicopters,

(i) Increase the RIN by 2 for each takeoff.

(ii) Increase the RIN by 2 for each external

load lift operation; or, increase the RIN by 4

for each external load lift in which the load

is picked up at a higher elevation and

released at a lower elevation and the

difference in elevation between the pick up

point and the release point is 200 feet or

greater.

(d) Remove the carrier, P/N’s 214–040–

077–007 or –101, from service on or before

attaining an accumulated RIN of 120,000.

The carrier is no longer retired based upon

flight hours. This AD revises the

Airworthiness Limitations section of the

maintenance manual by establishing a new

retirement life for the carrier of 120,000 RIN.

(e) 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, FAA, Rotorcraft

Directorate. 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 3: Information concerning the

existence of approved alternative methods of

compliance with this AD, if any, may be

obtained from the Rotorcraft Certification

Office.

(f) Special flight permits may be issued in

accordance with sections 21.197 and 21.199

of the Federal Aviation Regulations (14 CFR

21.197 and 21.199) to operate the helicopter

to a location where the requirements of this

AD can be accomplished.
1866 Federal Register / Vol. 62, No. 9 / Tuesday, January 14, 1997 / Proposed Rules

Issued in Fort Worth, Texas, on January 7,

1997.

Eric Bries,

Acting Manager, Rotorcraft Directorate,

Aircraft Certification Service.

[FR Doc. 97–879 Filed 1–13–97; 8:45 am]

BILLING CODE 4910–13–U

14 CFR Part 39

[Docket No. 96–NM–185–AD]

RIN 2120–AA64

Airworthiness Directives; Fokker

Model F28 Mark 0100 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 Fokker Model F28 Mark 0100

series airplanes. This proposal would

require repetitive inspections of certain

flanges and finger strips at rib 5.0 of the

vertical stabilizer to detect fatigue

cracking, and repairs, if necessary. It

also would require modifications that

would strengthen the torsion box at rib

5.0 and prevent fatigue cracking; one of

these modifications would be

terminating action for the repetitive

inspections. This proposal is prompted

by reports indicating that, during fullscale fatigue testing, cracking has been

found on the vertical stabilizer of the

test article. The actions specified by the

proposed AD are intended to detect and

prevent fatigue cracking in the subject

area, which, if not corrected, could

reduce the structural integrity of the

vertical stabilizer.

DATES: Comments must be received by

February 24, 1997.

ADDRESSES: Submit comments in

triplicate to the Federal Aviation

Administration (FAA), Transport

Airplane Directorate, ANM–103,

Attention: Rules Docket No. 96–NM–

185–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

Fokker Services B.V., Technical Support

Department, P.O. Box 75047, 1117 ZN

Schiphol Airport, The Netherlands. This

information may be examined at the

FAA, Transport Airplane Directorate,

1601 Lind Avenue, SW., Renton,

Washington.

FOR FURTHER INFORMATION CONTACT: Tim

Dulin, Aerospace Engineer,

Standardization Branch, ANM–113,

FAA, Transport Airplane Directorate,

1601 Lind Avenue, SW., Renton,

Washington 98055–4056; telephone

(206) 227–2141; 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–185–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–185–AD, 1601 Lind Avenue,

SW., Renton, Washington 98055–4056.

Discussion

The Rijksluchtvaartdienst (RLD),

which is the airworthiness authority for

the Netherlands, has notified the FAA

that an unsafe condition may exist on

certain Fokker Model F28 Mark 0100

series airplanes. The RLD advises that it

has received reports indicating that

cracks have been found on the vertical

stabilizer during the manufacturer’s fullscale fatigue tests on the Fokker Model

F28 Mark 0100 test article. These fatigue

cracks were detected at the bolt holes of

the right-hand flange of the torsion box,

and in the finger strip on the left-hand

flange at rib 5.0 of the vertical stabilizer.

The RLD also advises that it has

received reports indicating that

subsequent full-scale fatigue tests have

detected additional cracks in rib 5.0 of

the vertical stabilizer after a stiffener

had been added to the torsion box in

accordance with Fokker Service Bulletin

SBF100–55–018. Although this

modification was performed to

strengthen this area against fatigue

cracking, investigation has shown that

the stiffener produces a too-rapid

change in the structural strength of the

torsion box, which may lead to fatigue

cracking in an adjacent area.

Fatigue cracking in the subject area, if

not prevented, could reduce structural

integrity of the vertical stabilizer.

Explanation of Relevant Service

Information

Fokker has issued Service Bulletin

SBF100–55–019, Revision 1, dated May

19, 1993, which describes procedures

for conducting repetitive eddy current

inspections of the flanges and finger

strips at rib 5.0 of the vertical stabilizers

to detect fatigue cracking, and repair, if

necessary.

Fokker also has issued Service

Bulletin SBF100–55–018, Revision 1,

dated December 27, 1993, which

describes procedures for modifying the

torsion box at rib 5.0 of the vertical

stabilizer by installing stiffening to the

rib web and flanges for added strength.

This service bulletin also describes

procedures for a pre-modification eddy

current inspection of the vertical

stabilizer to detect cracking, and repair,

if necessary, in accordance with Fokker

Service Bulletin SBF100–55–019.

Accomplishment of this modification

eliminates the need for repetitive

inspections to detect fatigue cracking.

Additionally, Fokker has issued

Service Bulletin SBF100–55–023, dated

January 3, 1995, which describes

procedures for another modification to

strengthen rib 5.0 of the vertical

stabilizer. This modification, which

entails the cold expansion of holes in

the torsion box at rib 5.0, is intended to

prevent additional fatigue cracking that

could be caused by the earlier

installation of the torsion box stiffener.

The RLD classified these service

bulletins as mandatory and issued

Netherlands airworthiness directives

(BLA) 93–069 (A), dated June 1, 1993,

and BLA 1995–017 (A), dated February

28, 1995, in order to assure the

continued airworthiness of these

airplanes in the Netherlands.