AD 97-02-15 ACTIVE

This amendment supersedes an existing airworthiness directive (AD), applicable to Robinson Helicopter Company (Robinson) Model R44 helicopters, that currently requires an adjustment to the low RPM warning unit threshold to increase the revolutions-per-minute (RPM) at which the warning horn and caution light activate, and revisions to the R44 Rotorcraft Flight Manual that prohibit flight with the throttle governor (governor) selected off, except in certain situations. This amendment requires the same compliance actions required by the existing AD, and corrects the applicability section of the existing AD. This amendment is prompted by the need to expand the applicability statement of this AD to include all Robinson Model R44 helicopters. The actions specified by the proposed AD are intended to minimize the possibility of pilot mismanagement of the main rotor (M/R) RPM, which could result in unrecoverable M/R stall and subsequent loss of control of the helicopter.

Final rule

97-02-15 ROBINSON HELICOPTER COMPANY: Amendment 39-9900. Docket No. 96-SW-15-AD. Supersedes AD 96-11-09, Amendment 39-9634.

Applicability: Model R44 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 (c) 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 30 days after the effective date of this AD, unless accomplished previously.

To minimize the possibility of pilot mismanagement of the main rotor (M/R) RPM, which could result in unrecoverable M/R stall and subsequent loss of control of the helicopter, accomplish the following:

(a) Adjust the A569-6 low RPM warning unit so that the warning horn and caution light activate when the M/R RPM is between 96% and 97% rotor RPM in accordance with the procedures contained in the Model R44 maintenance manual.

(b) Revise the FAA-approved Robinson Helicopter Company R44 Rotorcraft Flight Manual (RFM) to include the following statement in the Limitations Section:
"Flight prohibited with governor selected off, with exceptions for inflight system malfunction or emergency procedures training."

This may be accomplished by inserting a copyof this AD or the FAA-approved Robinson Helicopter Company R44 RFM revision dated July 25, 1996 into the RFM.

(c) 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, Los Angeles Aircraft Certification Office, FAA. Operators shall submit their requests through an FAA Principal Maintenance Inspector, who may concur or comment and then send it to the Manager, Los Angeles Aircraft Certification Office.

NOTE 2: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Los Angeles Aircraft Certification Office.

(d) 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.

(e) This amendment becomes effective on March 4, 1997.

A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) by superseding AD 96-11-09, Amendment 39-9634 (61 FR 26427, May 28, 1996), which is applicable to Robinson Model R44 helicopters was published in the Federal Register on August 30, 1996 (61 FR 45918). That action proposed to require an adjustment to the low RPM warning unit threshold to increase the RPM at which the warning horn and caution light activate, and revisions to the R44 Rotorcraft Flight Manual that prohibit flight with the governor selected off, except in certain situations, for all Robinson Model R44 helicopters.

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, except for an editorial change to correct an error to the renumbering of the notes.

The FAA estimates that 20 helicopters of U.S. registry will be affected by this AD, that it will take approximately 0.2 work hour per helicopter to accomplish the actions, and that the average labor rate is $60 per work hour. Based on these figures, the total cost impact of the AD on U.S. operators is estimated to be $240.

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" underDOT 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 removing Amendment 39-9634 (61 FR 26427, May 28, 1996), and by adding a new airworthiness directive (AD), Amendment 39-9900, to read as follows:

Ms. Elizabeth Bumann, Aerospace Engineer, FAA, Los Angeles Aircraft Certification Office, 3960 Paramount Blvd., Lakewood, California 90712-4137, telephone (310) 627-5265; fax (310) 627-5210.