Airworthiness Directives; Bell Helicopter Textron, Inc., Model 214B, 214B-1 and 214ST Helicopters

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 94-SW-24-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).

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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 series helicopters, that

currently establishes a retirement life of 40,000 high-power events for

the lower planetary spider (spider). This action would require changing

the method of calculating the retirement life for the spider from high-

power events to a maximum accumulated Retirement Index Number (RIN) of

80,000 and would make this RIN applicable to an additional part

numbered spider. This proposal is prompted by fatigue analyses and

tests that show certain spiders fail sooner than originally anticipated

because of the unanticipated higher number of external load lifts and

takeoffs (torque events) performed with those spiders 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 spider, which could result in failure of the main

transmission and subsequent loss of control of the helicopter.

DATES: Comments must be received by January 13, 1997.

ADDRESSES: Submit comments in triplicate to the Federal Aviation

Administration (FAA), Office of the Assistant Chief Counsel, Attention:

Rules Docket No. 94-SW-24-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, Ft. Worth,

Texas 76101.

FOR FURTHER INFORMATION CONTACT: Mr. Uday Garadi, Aerospace Engineer,

FAA, Rotorcraft Certification Office, Rotorcraft Directorate, 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-24-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-24-AD, 2601 Meacham Blvd., Room 663, Fort Worth, Texas

76137.

Discussion

On August 13, 1993, the FAA issued AD 93-05-02, Amendment 39-8608

(58 FR 45833, August 31, 1993), to require changing the method of

calculating the retirement life for the spider, part number (P/N) 214-

040-080-101, from flight hours to high-power events calculated using

the number of takeoffs and external load lifts. That action was

prompted by reports of four failures of the spider, two of which were

detected during the 2,500 hour TIS overhaul inspection. The other two

failures occurred in flight. The requirements of that AD are intended

to prevent fatigue failure of the spider, 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-

53, which is applicable to the Model 214B helicopters, and ASB 214ST-

94-68, which is applicable to the 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

spider, P/N 214-040-080-001 and -101. Although ASB 214-94-53 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. Additionally, P/N 214-040-080-001

was omitted from the existing AD, and is included in the applicability

portion of this AD.

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

93-05-02 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 spider of 80,000.

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 to replace a spider affected by the new

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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 $10,920 per

helicopter. Based on these figures, the total cost impact of the

proposed AD on U.S. operators is estimated to be $28,220 for the first

year and $27,120 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 one-sixth 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 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.

Sec. 39.13 [Amended]

2. Section 39.13 is amended by removing Amendment 39-8608 (58 FR

45833, August 31, 1993) by adding a new airworthiness directive (AD),

to read as follows:

Bell Helicopter Textron, Inc. (BHTI): Docket No. 94-SW-24-AD.

Supersedes AD 93-05-02, Amendment 39-8608.

Applicability: Model 214B and 214B-1 helicopters, with lower

planetary spider (spider), part number (P/N) 214-040-080-001 or -

101, and Model 214ST series helicopters, with spider, P/N 214-040-

080-101, 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 (f) 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 spider, 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 for the main transmission

upper planetary spider (spider), part number (P/N) 214-040-080-001

or -101.

(b) For Model 214B and 214B-1 helicopters with spider, P/N 214-

040-080-001, determine and record the accumulated Retirement Index

Number (RIN) as follows:

(1) If the number of takeoffs and the number of external load

lifts conducted with this spider are known, record one (1) RIN for

each takeoff and one RIN for each external load lift.

(2) If either the number of takeoffs or the number of external

load lifts conducted with this spider are unknown, record twenty-

four (24) RIN for each hour TIS.

(3) If either the number of takeoffs or the number of external

load lifts conducted with this spider are unknown, or the hours TIS

are unknown, record twenty-one thousand, six hundred (21,600) RIN

for each calendar year TIS. Prorate the number of RIN, based on the

number of calendar day, for a portion of a year.

(c) For Model 214B, 214B-1, and 214ST helicopters with spider,

P/N 214-040-080-101, determine and record the accumulated RIN by

multiplying the high-power events by two (2).

Note 2: BHTI Alert Service Bulletin (ASB) No. 214-94-53, which

is applicable to Model 214B and 214B-1 helicopters, and ASB No.

214ST-94-68, which is applicable to Model 214ST helicopters, both

dated November 7, 1994, pertain to this subject.

(d) After complying with paragraphs (a) and (b) or (c) of this

AD, during each operation thereafter, maintain a count of the number

and type of external load lifts and the number of takeoffs

performed, and at the end of each day's operations, increase the

accumulated RIN on the component history card as follows:

(1) For the 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, 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 elevation between the pickup point

and the release point is 200 feet or greater.

(2) For the Model 214ST helicopter:

(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

operation in which the load is picked up at a higher elevation and

released at a lower elevation, and the difference in elevation

between the pickup point and the release point is 200 feet or

greater.

(e) Remove the spider, P/N 214-0400-080-001 or -101 from service

on or before attaining an accumulated RIN of 80,000. The spider 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 spider of 80,000 RIN.

(f) 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.

(g) 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.

Issued in Fort Worth, Texas, on November 5, 1996.

Eric Bries,

Acting Manager, Rotorcraft Directorate, Aircraft Certification Service.

[FR Doc. 96-29102 Filed 11-13-96; 8:45 am]

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