Document Headings

                    Document headings vary by document type but may contain                    the following:                  
                -                       the agency or agencies that issued and signed a document                    
                -                       the number of the CFR title and the number of each part                      the document amends, proposes to amend, or is directly                      related to                    
                -                       the agency docket number / agency internal file number                    
                -                       the RIN which identifies each regulatory action listed in                      the Unified Agenda of Federal Regulatory and Deregulatory                      Actions                    

                    See the                                          Document Drafting Handbook                                        for more details.                  

###### Department of Transportation

###### Federal Aviation Administration

          - 14 CFR Part 39
          - [Docket No. 99-SW-34-AD]
          - RIN 2120-AA64

# AGENCY:

Federal Aviation Administration, DOT.

# ACTION:

Notice of proposed rulemaking.

# SUMMARY:

This document proposes revising an existing airworthiness directive (AD) for Eurocopter France (ECF) Model SA-365N1, AS-365N2, and SA-366G1 helicopters. That AD currently requires inspecting each tail rotor blade for bonding separation, measuring the clearance between the tip of each tail rotor blade and the circumference of the air duct, and replacing the blade if necessary. This action would contain the same requirements but would allow the pilot to perform the daily visual check and would contain a damage allowance for certain blades. This proposal is prompted by FAA determination that the pilot can check for a cracked, blistered, or wrinkled blade and that some debonding of the blade is acceptable. The actions specified by the proposed AD are intended to allow a pilot check, to prevent unacceptable damage to a tail rotor blade, and to prevent loss of tail rotor control and subsequent loss of control of the helicopter.

# DATES:

Comments must be received by August 10. 2001.

# ADDRESSES:

Submit comments in triplicate to the Federal Aviation Administration (FAA), Office of the Regional Counsel, Southwest Region, Attention: Rules Docket No. 99-SW-34-AD, 2601 Meacham Blvd., Room 663, Fort Worth, Texas 76137. You may also send comments electronically to the Rules Docket at the following address: 9-asw-adcomments@faa.gov. Comments may be inspected at the Office of the Regional Counsel between 9 a.m. and 3 p.m., Monday through Friday, except Federal holidays.

# FOR FURTHER INFORMATION CONTACT:

Sharon Miles, Aviation Safety Engineer, FAA, Rotorcraft Directorate, Regulations Group, Fort Worth, Texas 76193-0111, telephone (817) 222-5122, fax (817) 222-5961.

# 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 will be considered before taking action on the proposed rule. The proposals contained in this document 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 in the Rules Docket for examination by interested persons. A report summarizing each FAA-public contact concerned with the substance of this document will be filed in the Rules Docket.

Commenters wishing the FAA to acknowledge receipt of their mailed comments submitted in response to this proposal must submit a self-addressed, stamped postcard on which the following statement is made: “Comments to Docket No. 99-SW-34-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 Regional Counsel, Southwest Region, Attention: Rules Docket No. 99-SW-34-AD, 2601 Meacham Blvd., Room 663, Fort Worth, Texas 76137.

## Discussion

                    On May 9, 2000, the FAA issued AD 2000-10-08, Amendment No. 39-11732 (65 FR 31256) to require inspecting each tail rotor blade for bonding separation, measuring the clearance between the tip of each tail rotor blade and the circumference of the air duct, and replacing a blade if necessary. That action was prompted by an inflight incident in which the tail rotor blades were significantly damaged due to bonding separation. That condition, if                           ( print page 31190)                        not corrected, could result in loss of tail rotor control and subsequent loss of control of the helicopter.                

Since the issuance of that AD, the FAA has reevaluated the requirements due to reports from operators that the AD has placed an unnecessary burden on them and that a pilot should be allowed to perform the check. ECF has issued Service Bulletins 05.09 and 05.00.17, both dated December 18, 1998; and based on these service bulletins, the Direction Generale De L'Aviation Civile (DGAC) (France) has issued AD's 88-152-010(A)R5 and 88-153-023(A)R5, both dated December 30, 1998. The FAA has reviewed these documents and determined that the pilot may perform the check and that some debonding is acceptable.

These helicopter models are manufactured in France and are type certificated for operation in the United States under the provisions of 14 CFR 21.29 and the applicable bilateral airworthiness agreement. Pursuant to this bilateral airworthiness agreement, the DGAC has kept the FAA informed of the situation described above. The FAA has examined the findings of the DGAC, reviewed all available information, and determined that AD action is necessary for products of this type design that are certificated for operation in the United States.

An owner/operator (pilot) may perform the visual check required by this AD and enter compliance with the visual check provisions in paragraph (a) of this AD in accordance with 14 CFR 43.11 and 91.417(a)(2)(v). This AD allows a pilot to perform the check because it involves only a visual check of the tail rotor blades for a crack, wrinkling, or a blister and can be performed equally well by a pilot or a mechanic.

Since we have identified an unsafe condition that is likely to exist or develop on other ECF Model SA-365N1, AS-365N2, and SA-366G1 helicopters of the same type design, the proposed AD would contain the same requirements as the existing AD. However, the proposed AD would revise AD 2000-10-08 to allow a “visual” check of each tail rotor blade for a crack, wrinkling, or a blister within 10 hours time-in-service (TIS) and thereafter before the first flight of each day. The proposed AD would also allow some debonding in blades, part number 365A12-0020-02 and 365A12-0020-03.

The FAA estimates that 136 helicopters of U.S. registry would be affected by this proposed AD. If a tapping inspection is required, it would take approximately 1 work hour per helicopter to conduct, and that the average labor rate is $60 per work hour. If necessary, replacing a blade would take approximately 4 hours and required parts would cost approximately $1,000 per helicopter. Based on these figures, the total cost impact of the AD on U.S. operators is estimated to be $176,800, assuming a blade must be replaced on each affected helicopter.

The regulations proposed herein would not have a substantial direct effect 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, it is determined that this proposed rule would not have federalism implications under Executive Order 13132.

For the reasons discussed above, I certify that this proposed 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) if promulgated, would 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 has been prepared for this action is contained in the Rules Docket. A copy of it may be obtained from the Rules Docket at the FAA, Office of the Regional Counsel, Southwest Region, 2601 Meacham Blvd., Room 663, Fort Worth, Texas.

# 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

2. Section 39.13 is amended by removing Amendment 39-11732 (65 FR 31256) and by adding a new airworthiness directive to read as follows:

**Eurocopter France:**                                 Docket No. 99-SW-34-AD. Revises AD 2000-10-08, Amendment 39-11732, Docket No. 99-SW-34-AD.                            

*Applicability:*                                 Model SA-365N1, AS-365N2, and SA-366G1 helicopters, with a tail rotor blade, part number (P/N) 365A33-2131, 365A12-0010, or 365A12-0020, all dash numbers, 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 otherwise 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 request approval for an alternative method of compliance in accordance with paragraph (e) of this AD. The request should include an assessment of the effect of the modification, alteration, or repair on the unsafe condition addressed by this AD; and if the unsafe condition has not been eliminated, the request should include specific proposed actions to address it.

*Compliance:*                                 Required as indicated, unless accomplished previously.                            

To prevent damage to a tail rotor blade (blade), loss of tail rotor control, and subsequent loss of control of the helicopter:

(a) Within 10 hours time-in-service (TIS) and thereafter before the first flight of each day, visually check each blade (see Figure 1) for a crack, blister, or wrinkling. An owner/operator (pilot), holding at least a private pilot certificate, may perform the visual check and must enter compliance into the aircraft maintenance records in accordance with 14 CFR sections 43.11 and 91.417(a)(2)(v)).

(b) If a crack, blister, or wrinkling is found as a result of the visual check, accomplish the following before further flight (see Figure 1):

(1) Zone A: If a blister is detected on the blade suction face, conduct a tapping test inspection on the whole blade for bonding separation.

(i) For blades, P/N 365A33-2131-all dash numbers, 365A12-0010-all dash numbers, and 365A12-0020-00, and -01, if bonding separation or a crack is found, replace the blade with an airworthy blade before further flight.

                                (ii) For blades, P/N 365A12-0020-02, and -03, if bonding separation exceeds 900 mm2                                 in a 30 x 30 mm square or if there is a crack, replace the blade with an airworthy blade before further flight.                            

(2) Zone B: If a crack, wrinkling, or a blister is found, replace the blade with an airworthy blade before further flight.
      ( print page 31191)          ( print page 31192)    
(c) Within 10 hours TIS, conduct a tapping test inspection on each blade. If there is bonding separation that exceeds the criteria in paragraph b(1) of this AD, replace the blade with an airworthy blade before further flight.

# Note 2:

Revisions 5 of Eurocopter France Service Bulletins 05.09 and 05.00.17, both dated December 18, 1998, pertain to the subject of this AD.

(1) Thereafter, at intervals not to exceed 25 hours TIS or every 50 cycles (each takeoff and landing equals 1 cycle), whichever occurs first, conduct a tapping test inspection for bonding separation on all blades with a serial number (S/N) less than 18912, and blades, P/N 365A12-0020-00 or 365A12-0020-01, with a S/N equal to or greater than 18912. If bonding separation or a crack is found, replace the blade with an airworthy blade before further flight.

(2) Thereafter, at intervals not to exceed 100 hours TIS or 200 cycles, whichever occurs first, conduct a tapping test inspection for bonding separation on blades, P/N 365A12-0020-02 or 365A12-0020-03. For Zone A, if bonding separation exceeds the criteria specified in paragraph (b)(1)(ii) of this AD or if a crack is found, replace the blade with an airworthy blade before further flight. For Zone B, if a crack, wrinkling, or a blister is found, replace the blade with an airworthy blade before further flight.

(d) Within 10 hours TIS, and thereafter at intervals not to exceed 100 hours TIS or 200 cycles, whichever occurs first, measure the blade-to-air duct clearance. If the clearance is less than 3 mm, replace the blade with an airworthy blade before further flight.

(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, Regulations Group, 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, Regulations Group.

# Note 3:

Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Regulations Group.

(f) Special flight permits may be issued in accordance with 14 CFR 21.197 and 21.199 to operate the helicopter to a location where the requirements of this AD can be accomplished.

# Note 4:

The subject of this AD is addressed in Direction Generale De L'Aviation Civile AD's 88-152-010(A)R5 and 88-153-023(A)R5, both dated December 30, 1998.

Issued in Fort Worth, Texas, on May 31, 2001.

Eric Bries,

Acting Manager, Rotorcraft Directorate, Aircraft Certification Service.

BILLING CODE 4910-13-U

BILLING CODE 4910-13-C

[FR Doc. 01-14536 Filed 6-8-01; 8:45 am]