AD 2001-26-53

Historical

Emergency airworthiness directive · Servocontrols · Eurocopter France AS-350B, AS-350B1, AS-350B2 and 3 more

Effective
February 6, 2002
Published
January 22, 2002 · 67 FR 2804–2806
Issued
December 21, 2001
Superseded by
AD2003-22-11
Models
AS-350B, AS-350B1, AS-350B2, AS-350B3, AS-350BA, AS355E
Registered aircraft
918 matched by model
Product
Aircraft · Rotorcraft
Amendment
39-12605
Docket
2001-SW-70-AD
Issued as
Final rule; request for comments

Unofficial copy from the Federal Register XML, document 02-1450. Only the govinfo PDF is the legal edition. DRS record last changed August 7, 2025.

On this page

Summary

This document publishes in the Federal Register an amendment adopting Airworthiness Directive (AD) 2001-26-53, which was sent previously to all known U.S. owners and operators of Eurocopter France (ECF) Model AS350B, B1, B2, B3, BA, D, and AS355E helicopters by individual letters. This AD requires, before further flight, removing certain serial-numbered servocontrols. This AD is prompted by a report of manufacturing defects in a batch of main servocontrol rods. The actions specified by this AD are intended to prevent failure of a main servocontrol in the flight control system and subsequent loss of control of the helicopter.

The airworthiness directive

2001-26-53 Eurocopter France: Amendment 39-12605. Docket No. 2001-SW-70-AD.

Applicability: Model AS350B, B1, B2, B3, BA, D, and AS355E helicopters, with TRW-SAMM main servocontrols, part number (P/N) SC 5083, serial number (S/N) from 1500 to 1515, inclusive, or P/N SC 5084, S/N from 722 to 726, inclusive, installed, except those reconditioned and identified by the letter “V” engraved on the identification plate on the right-hand side of the P/N, 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 (b) 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 before further flight, unless accomplished previously.

To prevent failure of a main servocontrol, failure of the flight control system, and subsequent loss of control of the helicopter, accomplish the following:

(a) Remove each affected main servocontrol.

Note 2:

Eurocopter France Alert Telex Nos. 01.00.52 and 01.00.18, both dated November 15, 2001, pertain to the subject of 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, Regulations Group, 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.

(c) Special flight permits will not be issued.

(d) This amendment becomes effective on February 6, 2002, to all persons except those persons to whom it was made immediately effective by Emergency AD 2001-26-53, issued December 21, 2001, which contained the requirements of this amendment.

Note 4:

The subject of this AD is addressed in Direction Generale De L'Aviation Civile, France, AD Nos. T2001-590-087(A) and T2001-591-065(A), both dated November 28, 2001.

Rule preamble

The FAA’s background, reasoning and cost estimate, published with the AD.

DatesPage 1

Effective February 6, 2002 to all persons except those persons to whom it was made immediately effective by Emergency AD 2001-26-53, issued on December 21, 2001, which contained the requirements of this amendment.

Comments for inclusion in the Rules Docket must be received on or before March 25, 2002.

AddressesPage 1

Submit comments in triplicate to the Federal Aviation Administration (FAA), Office of the Regional Counsel, Southwest Region, Attention: Rules Docket No. 2001-SW-70-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.

For further information contactPage 1

Uday Garadi, Aviation Safety Engineer, FAA, Rotorcraft Directorate, Rotorcraft Standards Staff, Fort Worth, Texas 76193-0110, telephone (817) 222-5123, fax (817) 222-5961.

Supplementary informationPage 2

On December 21, 2001, the FAA issued Emergency AD 2001-26-53, for ECF Model AS350B, B1, B2, B3, BA, D, and AS355E helicopters, which requires, before further flight, removing certain serial-numbered servocontrols. That action was prompted by a report of manufacturing defects in a batch of main servocontrol rods. This condition, if not corrected, could result in failure of a main servocontrol in the flight control system and subsequent loss of control of the helicopter.

The FAA has reviewed ECF Alert Telex Nos. 01.00.52 and 01.00.18, both dated November 15, 2001, which advise replacing certain servocontrols.

The Direction General De L'Aviation Civile (DGAC), the airworthiness authority for France, notified the FAA that an unsafe condition may exist on ECF Model AS350B, B1, B2, B3, BA, D, and AS355E helicopters. The DGAC advises of the discovery of a manufacturing defect on a batch of rods of the main servocontrol, the failure of which would lead to the loss of control of the helicopter. The DGAC classified the ECF Alert Telexes as mandatory and issued AD No. T2001-590-087(A) (for AS 350 helicopters) and No. T2001-591-065(A) (for AS 355 helicopters), both dated November 28, 2001, to ensure the continued airworthiness of these helicopters.

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 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 these type designs that are certificated for operation in the United States.

The unsafe condition is likely to exist or develop on other helicopters of the same type design. Therefore, the FAA issued Emergency AD 2001-26-53 to prevent failure of a main servocontrol, failure of the flight control system, and subsequent loss of control of the helicopter. The AD requires, before further flight, removing certain serial-numbered servocontrols. This AD does not apply to certain reconditioned servocontrols identified by the letter “V” engraved on the identification plate on the right-hand side of the part number. The short compliance time involved is required because the previously described critical unsafe condition can adversely affect the structural integrity and controllability of the helicopter. Therefore, removing certain serial-numbered servocontrols is required before further flight, and this AD must be issued immediately.

Since it was found that immediate corrective action was required, notice and opportunity for prior public comment thereon were impracticable and contrary to the public interest, and good cause existed to make the AD effective immediately by individual letters issued on December 21, 2001 to all known U.S. owners and operators of ECF Model AS350B, B1, B2, B3, BA, D, and AS355E helicopters. These conditions still exist, and the AD is hereby published in the Federal Register as an amendment to 14 CFR 39.13 to make it effective to all persons.

The FAA estimates that 540 helicopters of U.S. registry will be affected by this AD. It will take approximately 2 work hours per helicopter to remove a main servocontrol. The average labor rate is $60 per work hour. Required parts will cost approximately $9200 per main servocontrol. Based on these figures, the total cost impact of the AD on U.S. operators is estimated to be $5,032,800 ($9320 per helicopter), assuming that at least one main servocontrol is replaced on each helicopter.

Comments invitedPage 2

Although this action is in the form of a final rule that involves requirements affecting flight safety and, thus, was not preceded by notice and an opportunity for public comment, comments are invited on this rule. Interested persons are invited to comment on this 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 under the caption ADDRESSES. All communications received on or before the closing date for comments will be considered, and this rule may be amended in light of the comments received. Factual information that supports the commenter's ideas and suggestions is extremely helpful in evaluating the effectiveness of the AD action and determining whether additional rulemaking action would be needed.

Comments are specifically invited on the overall regulatory, economic, environmental, and energy aspects of the rule that might suggest a need to modify the rule. All comments submitted will be available in the Rules Docket for examination by interested persons. A report that summarizes each FAA-public contact concerned with the substance of this AD will be filed in the Rules Docket.

Commenters wishing the FAA to acknowledge receipt of their mailed comments submitted in response to this rule must submit a self-addressed, stamped postcard on which the following statement is made: “Comments to Docket No. 2001-SW-70-AD.” The postcard will be date stamped and returned to the commenter.

The regulations adopted herein will 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 final rule does not have federalism implications under Executive Order 13132.

The FAA has determined that this regulation is an emergency regulation that must be issued immediately to correct an unsafe condition in aircraft, and that it is not a “significant regulatory action” under Executive Order 12866. It has been determined further that this action involves an emergency regulation under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979). If it is determined that this emergency regulation otherwise would be significant under DOT Regulatory Policies and Procedures, a final regulatory evaluation will be prepared and placed in the Rules Docket. A copy of it, if filed, 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.

Adoption of the amendmentPage 2

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:

1. The authority citation for part 39 continues to read as follows:

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

Affected TCDS · 2

The type certificate data sheets for the models this AD names, matched by model and maker.

Registered aircraft · 918

Registered aircraft whose airframe or engine model this AD names. Matched by model only, so check each against the AD’s applicability.

By aircraft maker
  • Airbus Helicopters359 aircraft
  • Eurocopter327 aircraft
  • American Eurocopter162 aircraft
  • Aerospatiale45 aircraft
  • Eurocopter France19 aircraft
  • S N I A S6 aircraft
By year built
19782026
Registered aircraft by year built: 821 aircraft
19782
19798
19804
19814
19825
19844
19851
19862
19875
19888
19895
19906
19915
19926
19933
19944
19958
19968
19976
199822
199915
200020
200124
200228
200316
200418
200515
200618
200728
200840
200931
201028
201123
201230
201342
201445
201519
201613
201724
201823
201933
202017
202122
202233
202336
202429
202522
202613

97 with no year recorded

By model

See all 21 models

Aircraft

See all 918 aircraft