AD 99-05-07

This amendment adopts a new airworthiness directive (AD), applicable to Bell Helicopter Textron, Inc. (BHTI) Model 214B and 214B-1 helicopters, that requires creation of a component history card or an equivalent record using the Retirement Index Number (RIN) system, establishing a system for tracking increases to the accumulated RIN, and establishing a maximum accumulated RIN for the pillow block bearing bolts (bearing bolts) of 17,000 before they must be removed from service. This amendment is prompted by fatigue analyses and tests that show certain bearing bolts fail sooner than originally anticipated because of the unanticipated high number of lifts and takeoffs (torque events) performed with those bearing bolts in addition to the time-in-service (TIS) accrued under other operating conditions. The actions specified by this AD are intended to prevent fatigue failure of the bearing bolts, which could result in failure of the main rotor system and subsequent loss of control ofthe helicopter.

Final rule

99-05-07 BELL HELICOPTER TEXTRON, INC.: Amendment 39-11055. Docket No. 94-SW-23-AD.

Applicability: Model 214B and 214B-1 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 (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), unless accomplished previously.

To prevent fatigue failure of the pillow block bearing bolts (bearing bolts), part number (P/N) 20-057-12-48D or -50D, which could result in failure of the main rotor system and subsequent loss of control of the helicopter, accomplish the following:

(a) Create a Retirement Index Number (RIN) component history card or an equivalent record for the bearing bolts, P/N 20-057-12-48D or -50D.

(b) Calculate and record on the component history card the historical accumulated RIN for the bearing bolts as follows:

(1) When the type of operation (internal or external load lift), actual flight hours, and number of external load lifts or takeoffs per hour are known, multiply the actual flight hours by the appropriate factor in the following table for external load lift operation:

Average No. ofExternal Load Lift Events Per Flight Hour
Factor
0 - 2.00
6.8
2.01 - 5.00
13.6
5.01 - 16.00
27.2
16.01 - 27.00
40.8
Above 27.00
54.4

When the type of operation is internal load and no external lifting is involved, each hour of actual operating time is equal to 6.8 RIN.

(2) When the actual flight hours on the bolts are known, but the type of operation (internal or external load lift) is unknown, multiply the actual flight hours by a factor of 40.8.

(3) When the actual flight hours on the bolts are unknown, assume 75 flight hours per month.

(4) When the flight hours on the bolts are assumed, but the type of operation (internal or external load lift) is known,

(i) Multiply the number of flight hours assumed for internal load operations by a factor of 6.8.

(ii) Multiply the number of flight hours assumed for external load operations by a factor of 40.8.

(5) When the flight hours on the bolts are assumed and the type of operation (internal or external load lift) is unknown, multiply the assumed flight hours by a factor of 40.8.

(c) After compliance with paragraphs (a) and (b) of this AD, 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 bearing bolts component history card as follows:

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

(2) Increase the RIN by 1 for each external load lift, or increase the RIN by 2 for each external load 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.

NOTE 2: Bell Helicopter Textron, Inc. Alert Service Bulletin No. 214-94-54, dated November 7, 1994, pertains to the subject of this AD.

(d) Remove the bearing bolts from service on or before attaining an accumulated RIN of 17,000. The bearing bolts are no longer retired based upon flight hours. If any of the four bolts require replacement for any reason, then all four bolts must be replaced at that time. This AD revises the Airworthiness Limitations section of the maintenance manual by establishing a new retirement life for the bearing bolts of 17,000 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, 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 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 FederalAviation Regulations (14 CFR 21.197 and 21.199) to operate the helicopter to a location where the requirements of this AD can be accomplished.

(g) This amendment becomes effective on May 3, 1999.

A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) to include an AD that is applicable to BHTI Model 214B and 214B-1 helicopters was published in the Federal Register on July 6, 1998 (63 FR 36377). That action proposed to require creation of a component history card or an equivalent record using the RIN system, establishing a system for tracking increases to the accumulated RIN, and establishing a maximum accumulated RIN for the bearing bolts of 17,000 before they must be removed from service.

Interested persons have been afforded an opportunity to participate in the making of this amendment. No comments were received on the proposal or the FAA's determination of the cost to the public. The FAA has determined that air safety and the public interest require the adoption of the rule as proposed.

The FAA estimates that 54 helicopters of U.S. registry will be affected by this AD, that it will take, per helicopter, approximately (1) 24 work hours to replace the affected bearing bolts due to the new method of determining the retirement life; (2) 2 work hours to create the component history card or equivalent record (record); and (3) 10 work hours to maintain the record each year; and that the average labor rate is $60 per work hour. Required parts will cost approximately $2,000 per helicopter. Based on these figures, the total cost impact of the AD on U.S. operators is estimated to be $224,640 for the first year and $128,520 for each subsequent year. These costs assume replacement of the bearing bolts in the fleet the first year, and creation and maintenance of the records for all the fleet; and replacement of one-half of the fleet's bolts, creation of the records for one-half of the fleet, and maintenance of the records for all the fleet each subsequent year.

The regulations adopted herein will not have substantial direct effects on the States, on the relationship between thenational 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.

For the reasons discussed above, I certify that this action (1) is not a " significant regulatory action" under Executive Order 12866; (2) is not a "significant rule" under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and (3) 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 final evaluation has been prepared for this action and it is contained in the Rules Docket. A copy of it may be obtained from the Rules Docket at the Federal Aviation Administration (FAA), Office of the Regional Counsel, Southwest Region, Attention: Rules Docket No. 94-SW-23-AD, 2601 Meacham Blvd., Room 663, Fort Worth, Texas 76137.

List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, 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: