AD 96-23-01

Active

Kratos Indicator

Key Information
96-23-01
Active
December 11, 1996
Not specified
95-SW-35-AD
39-9806
Applicability
["Aircraft"]
["Rotorcraft"]
Bell Helicopter Textron Canada Limited
206L-1
Summary

This amendment adopts a new airworthiness directive (AD), applicable to Bell Helicopter Textron, A Division of Textron Canada, Ltd. (BHTC) Model 206L-1 helicopters that have a Kratos turbine outlet temperature (TOT) indicator (Kratos indicator) installed, that requires replacing certain Kratos indicators. This amendment is prompted by manufacturer's tests and FAA analyses that show certain Kratos indicators may incorrectly provide low-temperature readings when the battery voltage is below 10 volts. The actions specified by this AD are intended to prevent false low-temperature indications, which could result in overheating of the engine turbine (turbine) and subsequent thermal fatigue damage to the turbine wheel.

Action Required

Final rule

Regulatory Text

96-23-01 BELL HELICOPTER TEXTRON, A DIVISION OF TEXTRON CANADA, LTD: Amendment 39-9806. Docket No. 95-SW-35-AD.

Applicability: Model 206L-1 helicopters that have a Kratos turbine outlet temperature (TOT) indicator (Kratos indicator), part number (P/N) 124.444-6 or 124.444-20, 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 (b) 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 90 days after the effective date of this AD, unless accomplished previously.

To prevent false low-temperature indications, which could result in overheating of the engine turbine (turbine) and subsequent thermal fatigue damage to the turbine wheel, accomplish the following:

(a) Remove the Kratos indicator, P/N 124.444-6 or 124.444-20, and replace it with an indicator, P/N 206-075-680-105 or P/N 206-375-006-101, or any other airworthy TOT indicator approved for use on the Bell Model 206L-1 helicopter, except for the Kratos TOT indicator, P/N 124.444-6 or 124.444-20.

NOTE 2: Bell Helicopter Textron, Inc. Alert Service Bulletin 206L-94-94, Revision A, dated July 11, 1994, pertains to this AD.

(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, 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.

(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 helicopter to a location where the requirements of this AD can be accomplished.

(d) This amendment becomes effective on December 11, 1996.

Supplementary Information

A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) to include an airworthiness directive (AD) that is applicable to BHTC Model 206L-1 helicopters was published in the Federal Register on April 10, 1996 (61 FR 15903). That action proposed to require removing the Kratos indicator and replacing it with an airworthy TOT indicator within 90 days after the effective date of this AD.

Interested persons have been afforded an opportunity to participate in the making of this amendment. Due consideration has been given to the comments received.

One commenter states that the AD should refer to the specific TOT indicator as is stated in the BHTC Model 206L-1 Illustrated Parts Catalog; otherwise, the AD will require owners/operators to obtain additional FAA approval since the particular part number referenced in the AD may not be reflected in any BHTC document. The FAA partially concurs. The FAA does not endorse specific vendors or manufacturers of parts unless those parts are the only parts authorized for use as replacements. There are alternative TOT indicator part numbers in the applicable helicopter parts catalog. The final rule will specify replacement TOT indicator part numbers, and the wording in the Compliance section has been revised to refer to using an airworthy replacement TOT indicator that is approved for this helicopter.

The same commenter states that the reference to the Alert Service Bulletin (ASB) should not be contained in a Note, and instead compliance in accordance with the ASB should be mandatory. The FAA does not concur. Generally, ASB s may be mandatory for Part 135 owners/operators, but not for Part 91 owners/operators.

Finally, the same commenter states that the AD should not require replacement of the TOT indicator, and should instead require owners/operators to ensure their helicopters electrical systems provide at least 10 volts during startup.The FAA does not concur that this should be included in the AD. There are procedures by which owners/operators may request permission to accomplish this as an alternate means of compliance.

After careful review of the available data, including the comments noted above, the FAA has determined that air safety and the public interest require the adoption of the rule as proposed.

The FAA estimates that 100 helicopters of U.S. registry will be affected by this AD, that it will take approximately 8 work hours per helicopter to accomplish the required actions, and that the average labor rate is $60 per work hour. Required parts will cost approximately $8,300 per helicopter. Based on these figures, the total cost impact of the AD on U.S. operators is estimated to be $878,000.

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.

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 location provided under the caption "ADDRESSES."

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 USC 106(g), 40113, 44701.

39.13 - [Amended]
2. Section 39.13 is amended by adding a new airworthiness directive to read as follows:

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Contact Information

Ms. Jennifer Kuehn, Aerospace Engineer, Rotorcraft Certification Office, Rotorcraft Directorate, FAA, 2601 Meacham Blvd., Fort Worth, Texas 76137, telephone (817) 222-5366, fax (817) 222-5960.

References
This information is not available.
--- - Part 39 [61 FR 57323 NO. 216 11/06/96]
FAA Documents