02-17301. Airworthiness Directives; Eurocopter France Model AS355N Helicopters

AGENCY:

Federal Aviation Administration, DOT.

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

This document proposes superseding an existing airworthiness directive (AD) for Eurocopter France (ECF) Model AS355N helicopters. The current AD requires visually inspecting the four engine exhaust pipe ejector (ejector) attachment lugs (lugs), the starter-generator (S-G) attachment flange (flange) and attachment half-clamps (half-clamps) for cracks, and the S-G shaft for radial play. This superseding AD would retain the current requirements, except would not require measuring the radial play but would require measuring each S-G engine clamp torque and vibration level and recording the S-G vibration level on a component history card or equivalent record. If the S-G vibration level is equal to or higher than 0.5 inches per second (IPS), this superseding AD would require repairing or replacing the S-G, as necessary. This proposal is prompted by additional cases of S-G damage and the need for additional corrective actions. The actions specified by this proposed AD are intended to prevent excessive S-G vibration, which could lead to separation of an ejector, impact with the main or tail rotor, and subsequent loss of control of the helicopter.

DATES:

Comments must be received on or before September 13, 2002.

ADDRESSES:

Submit comments in triplicate to the Federal Aviation Administration (FAA), Office of the Regional Counsel, Southwest Region, Attention: Rules Docket No. 2002-SW-32-AD, 2601 Meacham Blvd., Room 663, Fort Worth, Texas 76137. You may also send comments electronically to the Rules Docket at the following address: [e-mail]. Comments may be inspected at the Office of the Federal Register between 9 a.m. and 3 p.m., Monday through Friday, except Federal holidays.

FOR FURTHER INFORMATION CONTACT:

Ed Cuevas, Aviation Safety Engineer, FAA, Rotorcraft Directorate, Regulations Group, Fort Worth, Texas 76193-0110, telephone [phone], fax [phone].

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 proposal 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. 2002-SW-32-AD.” The postcard will be date stamped and returned to the commenter.

Discussion

This document proposes superseding an existing AD for ECF Model AS355N helicopters. This action would require determining the S-G clamp torque in accordance with the maintenance manual and the vibration level on both engines at specified intervals. This action would also require recording each vibration level on the component history card or equivalent record. If the S-G vibration level is equal to or higher than 0.5 IPS (12.7 mm/s), this action would require repairing or replacing the S-G, as necessary. Also, this action would require inspecting the lugs, the two clamps, and the flange for a crack and replacing any cracked part with an airworthy part before further flight. This proposal is prompted by reports of S-G damage, cracks in the lugs, and a report of in-flight loss of an ejector. The actions specified by the proposed AD are intended to prevent excessive S-G vibration, which could lead to separation of an ejector, impact with the main or tail rotor, and subsequent loss of control of the helicopter.

On March 6, 2000, the FAA issued AD 2000-05-15, Amendment 39-11625 (65 FR 14209), to require visually inspecting the four lugs, the flange, and the half-clamps for cracks and the S-G shaft for radial play. That action was prompted by reports of S-G damage, cracks in the lugs, and a report of in-flight loss of an ejector. The requirements of that AD are intended to prevent separation of an ejector from the helicopter, which could result in a main or tail rotor strike and subsequent loss of control of the helicopter.

Since the issuance of that AD, further cases of damage due to excessive S-G vibration have resulted in modifying the technical analysis and the precautionary measures.

The Direction Generale De L'Aviation Civile (DGAC), the airworthiness authority for France, notified the FAA that an unsafe condition may exist on Eurocopter France Model AS355N helicopters. The DGAC advises of further cases of S-G deterioration, which may lead to failure of the engine exhaust pipe lugs and loss of the ejector.

ECF has issued Eurocopter Alert Telex (Telex) No. 01.00.45 R3, dated November 22, 2001 that supersedes Alert Telex No. 01.00.45 R2, dated August 24, 2000, and No. 01.00.15 R2, dated April 3, 2000, that superseded Alert Telex No. 01.00.45, dated October 27, 1999. Alert Telex No. 01.00.45 R3 specifies checking the S-G clamp torque and vibration levels and recording vibration levels. If the vibration level is equal to or above 0.5 IPS (12.7 mm/s), Telex 01.00.45 R3 specifies repairing the S-G as well as conducting additional inspections and repairs. The Telex states that ECF is developing modifications to return to an acceptable maintenance program.

The DGAC classified Telex Nos. 01.00.45 R2 and 01.00.45 R3 as mandatory. The DGAC issued AD Nos. 1999-469-058(A)R1, dated August 9, 2000, and 1999-469-058(A)R2, dated January 9, 2002, to ensure the continued airworthiness of these helicopters in France.

This helicopter model is manufactured in France and is type certificated for operation in the United States under the provisions of 14 CFR 21.29 and the applicable bilateral agreement. Pursuant to the applicable bilateral 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.

This unsafe condition is likely to exist or develop on other ECF Model AS355N helicopters of this same type design. Therefore, the proposed AD would supersede AD 2000-05-15 to require determining the S-G clamp torque in accordance with the maintenance manual and measuring and recording the vibration level at specified intervals. If the vibration level is equal to or higher than 0.5 IPS, the AD would require repairing or replacing the S-G with an airworthy S-G, as necessary. In addition, the AD would require inspecting the lugs, the two clamps, and the flange for a crack, and replacing any cracked part with an airworthy part before further flight.

The FAA estimates that this proposed AD would:

• Affect 13 helicopters of U.S. registry;
• Require 5.5 work hours for the inspections;
• Require 5 work hours to replace the parts at an average labor rate of $60 per work hour;
• Cost approximately $6,346 for each S-G, $12,148 for each exhaust pipe, $500 for each flange, and $175 for each clamp or $38,338 per helicopter; and
• Result in a total cost impact of $506,584, assuming one inspection and replacement of all parts per 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 proposal would not have federalism implications under Executive Order 13132.

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.

§ 39.13

[Amended]

2. Section 39.13 is amended by removing Amendment 39-11625 (65 FR 14209, March 16, 2000), and by adding a new airworthiness directive (AD), to read as follows:

Eurocopter France: Docket No. 2002-SW-32-AD. Supersedes AD 2000-05-15, Amendment 39-11625, Docket No. 99-SW-87-AD.

Applicability: Model AS355N 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 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 excessive starter-generator (S-G) vibration, which may lead to separation of an engine exhaust pipe ejector (ejector), impact with the main or tail rotor, and subsequent loss of control of the helicopter, accomplish the following:

(a) Before further flight and at or between 10 and 15 hours time-in-service (TIS), inspect the torque on each S-G attachment clamp (clamp). If the torque is not within tolerances provided in the maintenance manual, adjust the torque accordingly.

(b) Measure and record on a component history card or equivalent record the vibration level for each S-G in accordance with the Accomplishment Instructions, paragraph 2.A.2., of Eurocopter France (ECF) Telex No. 01.00.45 R3, dated November 22, 2001 (Telex), as follows:

(1) For each S-G with less than 10 hours TIS since initial installation, before further flight, and at or between the hours TIS as shown in Table 1 of this AD:

Hours TIS

A. 10 and 15.

B. 24 and 35.

C. 45 and 55.

D. 70 and 80.

E. 100 and 110.

(2) For each S-G with 10 hours or more TIS but less than 110 hours TIS since initial installation, begin and continue the vibration level measurements at or between the applicable hours TIS shown in Table 1 of this AD.

(3) For each S-G with more than 110 hours TIS since initial installation, measure the vibration level before further flight.

(c) After doing paragraph (b) of this AD, thereafter, at intervals not to exceed 110 hours TIS, measure the vibration level in accordance with paragraph 2.A.2. of the Telex.

(d) If the vibration level of an S-G is equal to or greater than 0.5 inches per second (IPS) (12.7 mm/s):

(1) Remove the S-G and repair or replace it with an airworthy S-G.

(2) Visually inspect the four ejector attachment lugs (lugs) and the two clamps for a crack in accordance with the Accomplishment Instructions, paragraph 2.B.3.b.1B), of the Telex.

(3) Inspect the two half-clamps for a crack.

(4) Remove the S-G to engine attachment flange (flange). Clean and inspect the flange for a crack in accordance with the Accomplishment Instructions, paragraph 2.B.3.b.1D) of the Telex.

(5) If a crack is found, before further flight, repair or replace the cracked part with an airworthy part in accordance with the Accomplishment Instructions, paragraph 2.B.3.b.3 of the Telex, except you are not required to report your findings to the manufacturer.

(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 2:

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 3:

The subject of this AD is addressed in Direction Generale De L'Aviation Civile (France) AD Nos. 1999-469-058(A)R1, dated August 9, 2000, and 1999-469-058(A)R2, dated January 9, 2002.

Issued in Fort Worth, Texas, on July 3, 2002.

David A. Downey,

Manager, Rotorcraft Directorate, Aircraft Certification Service.