AD 2001-09-11

Recurring final rule

Airworthiness Directives; Bell Helicopter Textron, Inc. Model 412 Helicopters and Agusta S.p.A. Model AB412 Helicopters

AD Number
2001-09-11
Status
final_rule
Effective Date
Product Category
aircraft
Docket
Docket No. 99-SW-27-AD
FR Citation
66 FR 22913
Technical illustration of a helicopter rotor hub assembly
Problem area Rotor system

Applicability

TypeManufacturerModelDetails
aircraft Agusta S.p.A. | Bell Helicopter Textron, Inc. AB412 Airworthiness Directives; Bell Helicopter Textron, Inc. Model 412 Helicopters and Agusta S.p.A. Model AB412 Helicopters
aircraft Agusta S.p.A. | Bell Helicopter Textron, Inc. AB412 EP Airworthiness Directives; Bell Helicopter Textron, Inc. Model 412 Helicopters and Agusta S.p.A. Model AB412 Helicopters
aircraft Agusta S.p.A. | Bell Helicopter Textron, Inc. 412 Airworthiness Directives; Bell Helicopter Textron, Inc. Model 412 Helicopters and Agusta S.p.A. Model AB412 Helicopters
aircraft Agusta S.p.A. | Bell Helicopter Textron, Inc. 412CF Airworthiness Directives; Bell Helicopter Textron, Inc. Model 412 Helicopters and Agusta S.p.A. Model AB412 Helicopters
aircraft Agusta S.p.A. | Bell Helicopter Textron, Inc. 412EP Airworthiness Directives; Bell Helicopter Textron, Inc. Model 412 Helicopters and Agusta S.p.A. Model AB412 Helicopters

Unsafe Condition

Static and dynamic overload damage to the tail rotor yoke assembly that could result in loss of the tail rotor and subsequent loss of control of the helicopter.

AI-generated summary from the source AD text. Verify against the official source before acting.

Required Actions

Review historical records of the yoke assembly for overload damage; replace the yoke if damage is indicated; install a Vne red line at 120 knots KIAS; install a placard; insert applicable temporary revisions into the RFM; within 180 days, remove and replace the yoke assembly with an airworthy one; install an airworthy tail rotor flapping stop; remove temporary measures after compliance; and conduct recurring inspections at intervals not exceeding 25 hours TIS.

AI-generated summary from the source AD text. Verify against the official source before acting.

Compliance Time

Within 180 calendar days

AI-generated summary from the source AD text. Verify against the official source before acting.

Affected Aircraft

Bell Helicopter Textron, Inc. Model 412, 412CF, and 412EP helicopters and Agusta S.p.A. Model AB412 helicopters, with tail rotor yoke assembly, part number 212-011-702-all dash numbers, installed, certificated in any category.

AI-generated summary from the source AD text. Verify against the official source before acting.

Federal Register Abstract

This amendment supersedes an existing airworthiness directive (AD) that applies to certain serial-numbered Bell Helicopter Textron, Inc. (Bell) Model 412 helicopters and Agusta S.p.A. (Agusta) Model AB412 helicopters. That AD currently requires a temporary reduction of the never-exceed velocity (Vne) limitation until an inspection of the tail rotor yoke (yoke) assembly for fatigue damage and installation of a redesigned yoke flapping stop are accomplished. Recurring periodic and special inspections to detect occurrences of yoke overload are also required. This amendment requires the same actions as the previous AD but expands the applicability of the AD to all Bell Model 412, 412CF, 412EP, and Agusta Model AB412 helicopters. This amendment is prompted by the determination that the unsafe condition exists on all Bell Model 412 and all Agusta Model AB412 helicopters, regardless of serial number. The actions specified by this AD are intended to prevent static and dynamic overload damage to the yoke that could result in loss of the tail rotor and subsequent loss of control of the helicopter.

Document Text

Show stored source text (verify against official source)
[Federal Register Volume 66, Number 88 (Monday, May 7, 2001)]
[Rules and Regulations]
[Pages 22913-22914]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 01-10731]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 99-SW-27-AD; Amendment 39-12217; AD 2001-09-11]
RIN 2120-AA64


Airworthiness Directives; Bell Helicopter Textron, Inc. Model 412 
Helicopters and Agusta S.p.A. Model AB412 Helicopters

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

-----------------------------------------------------------------------

SUMMARY: This amendment supersedes an existing airworthiness directive 
(AD) that applies to certain serial-numbered Bell Helicopter Textron, 
Inc. (Bell) Model 412 helicopters and Agusta S.p.A. (Agusta) Model 
AB412 helicopters. That AD currently requires a temporary reduction of 
the never-exceed velocity (Vne) limitation until an inspection of the 
tail rotor yoke (yoke) assembly for fatigue damage and installation of 
a redesigned yoke flapping stop are accomplished. Recurring periodic 
and special inspections to detect occurrences of yoke overload are also 
required. This amendment requires the same actions as the previous AD 
but expands the applicability of the AD to all Bell Model 412, 412CF, 
412EP, and Agusta Model AB412 helicopters. This amendment is prompted 
by the determination that the unsafe condition exists on all Bell Model 
412 and all Agusta Model AB412 helicopters, regardless of serial 
number. The actions specified by this AD are intended to prevent static 
and dynamic overload damage to the yoke that could result in loss of 
the tail rotor and subsequent loss of control of the helicopter.

DATES: Effective June 11, 2001.
    The incorporation by reference of certain publications listed in 
the regulations was approved previously by the Director of the Federal 
Register as of April 8, 1998 (63 FR 14026, March 24, 1998), as 
corrected on July 20, 1998 (63 FR 38742).

ADDRESSES: The service information referenced in this AD may be 
obtained from Bell Helicopter Textron, Inc., P.O. Box 482, Fort Worth, 
Texas 76101, telephone (817) 280-3391, fax (817) 280-6466 for the Bell 
Model 412 helicopters; and Agusta S.p.A., 21017 Cascina Costa di 
Samarate (VA), Italy, Via Giovanni Agusta 520, telephone 39 (0331) 
229111, fax 39 (0331) 229605-222595 for the Agusta Model AB412 
helicopters. This information may be examined at the FAA, Office of the 
Regional Counsel, Southwest Region, 2601 Meacham Blvd., Room 663, Fort 
Worth, Texas; or at the Office of the Federal Register, 800 North 
Capitol Street, NW., suite 700, Washington, DC.

FOR FURTHER INFORMATION CONTACT: Uday Garadi, Aviation Safety Engineer, 
FAA, Rotorcraft Directorate, Rotorcraft Standards Staff, 2601 Meacham 
Blvd., Fort Worth, Texas 76137, telephone (817) 222-5123, fax (817) 
222-5961.

SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal 
Aviation Regulations (14 CFR part 39) by superseding AD 98-07-03, 
Amendment 39-10421 (63 FR 14026, March 24, 1998), which applies to 
certain serial-numbered Bell Model 412 helicopters and Agusta Model 
AB412 helicopters, was published in the Federal Register on January 22, 
2001 (66 FR 6494). That action proposed to require a reduction of the 
Vne limitation until an inspection of the yoke assembly for static and 
dynamic overload damage and installation of a redesigned yoke flapping 
stop are accomplished and includes periodic and special inspections to 
detect a yoke overload. A correction to a technical bulletin date 
referenced in that AD was issued on July 10, 1998 (63 FR 38742, July 
20, 1998).
    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 clarifying changes that 
were made in paragraph (a) to better explain the intent of the AD and 
editorial changes in paragraph (d). The FAA has determined that these 
changes will neither increase the economic burden on any operator nor 
increase the scope of the AD.
    The FAA estimates that 135 helicopters of U.S. registry will be 
affected by this AD, that it will take approximately 6.5 work hours per 
helicopter to install the placard, inspect the yoke assembly, and 
install the yoke. Required parts will cost approximately $511 per 
helicopter. Based on these figures, the total cost impact of this AD on 
U.S. operators is estimated to be $121,635.
    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

[[Page 22914]]

levels of government. Therefore, it is determined that this final rule 
does not have federalism implications under Executive Order 13132.
    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, Incorporation by 
reference, 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 U.S.C. 106(g), 40113, 44701.


Sec. 39.13  [Amended]

    2. Section 39.13 is amended by removing Amendment 39-10421 (63 FR 
14026, March 24, 1998, and 63 FR 38742, July 20, 1998), and by adding a 
new airworthiness directive (AD), Amendment 39-12217, to read as 
follows:

2001-09-11  Bell Helicopter Textron, Inc. and Agusta S.p.A.: 
Amendment 39-12217. Docket No. 99-SW-27-AD. Supersedes AD 98-07-03, 
Amendment 39-10421, Docket No. 97-SW-58-AD.

    Applicability: Bell Helicopter Textron, Inc. Model 412, 412CF, 
and 412EP helicopters and Agusta S.p.A. Model AB412 helicopters, 
with tail rotor yoke assembly, part number (P/N) 212-011-702-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 static and dynamic overload damage to the tail rotor 
yoke (yoke) that could result in loss of the tail rotor and 
subsequent loss of control of the helicopter, accomplish the 
following:
    (a) Before further flight, review the historical records of the 
yoke assembly for any static or dynamic overload damage that could 
have imposed a bending load on the yoke. The damage may not have 
required replacing the yoke assembly; for example, an incident in 
which a damaged tail rotor blade was replaced due to a blade strike. 
If the records indicate that overload damage may have occurred, 
replace the yoke with an airworthy yoke.
    (b) Before further flight, unless the requirements of paragraph 
(c) of this AD have been accomplished previously:
    (1) Install a Never Exceed Velocity (Vne) red line at 120 knots 
indicated airspeed (KIAS) on the pilot and copilot airspeed 
indicators using red tape or paint and a slippage indicator on the 
instrument case and glass.
    (2) Install a placard made of material that is not easily 
erased, disfigured, or obscured on the instrument panel in clear 
view of the pilot and copilot:
    ``Observe temporary Maximum Never Exceed (Vne) airspeed red line 
(marked at 120 knots indicated airspeed (KIAS)). Vne is 20 KIAS less 
than the value presented on the airspeed limitation placard for each 
ambient condition.''
    (3) Insert the applicable Bell Helicopter Textron (BHT) 412 
Temporary Revision, dated August 16, 1996, into the Model 412 
Rotorcraft Flight Manual (RFM) or the applicable section of Agusta 
AB412 Temporary Revision No. 2, dated April 17, 1997, into the Model 
AB412 RFM.
    (c) Within 180 calendar days:
    (1) Remove yoke assembly, P/N 212-011-702-all dash numbers, and 
replace it with an airworthy yoke assembly, P/N 212-011-702-all dash 
numbers, with zero hours time-in-service (TIS), or an airworthy yoke 
(regardless of TIS) that has passed a one-time x-ray diffraction 
inspection in accordance with BHT Alert Service Bulletin (ASB) 412-
96-89, Revision A, dated October 17, 1997; BHT ASB 412CF-96-01, 
dated September 3, 1996; or Agusta Bolletino Tecnico (Technical 
Bulletin) No. 412-65, dated April 17, 1997, whichever is applicable.
    (2) Install an airworthy tail rotor flapping stop, P/N 212-011-
713-103.
    (3) After the requirements of paragraphs (c)(1) and (c)(2) of 
this AD are accomplished, remove the 120 KIAS redline from the pilot 
and copilot airspeed indicators; remove the Vne airspeed restriction 
placard; and remove the BHT 412 Temporary Revision, dated August 16, 
1996; BHT ASB 412CF-96-01, dated September 3, 1996; or Agusta AB412 
Temporary Revision No. 2, as applicable, from the RFM.
    (d) After accomplishing the requirements of paragraph (c) of 
this AD, at intervals not to exceed 25 hours TIS, inspect the yoke 
assembly and tail rotor flapping stop (stop) in accordance with Part 
III, Recurring 25-Hour Special Inspection and Conditional Inspection 
Requirement, of BHT ASB 412-96-89, Revision A, dated October 17, 
1997; BHT ASB 412CF-96-01, dated September 3, 1996; or Agusta 
Technical Bulletin No. 412-65, dated April 17, 1997, as applicable. 
Replace any unairworthy yoke assembly or stop with an airworthy yoke 
assembly or stop 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 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 
Secs. 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 
21.197 and 21.199) to operate the helicopter at airspeeds not to 
exceed 120 KIAS to a location where the requirements of this AD can 
be accomplished.
    (g) The inspections and installations shall be done in 
accordance with Bell Helicopter Textron Alert Service Bulletin 412-
96-89, Revision A, dated October 17, 1997; Bell Helicopter Textron 
Alert Service Bulletin 412CF-96-01, dated September 3, 1996; or 
Agusta Bolletino Tecnico (Technical Bulletin) No. 412-65, dated 
April 17, 1997. The incorporation by reference of those documents 
was approved previously by the Director of the Federal Register, in 
accordance with 5 U.S.C. 552(a) and 1 CFR part 51, as of April 8, 
1998 (63 FR 14026, March 24, 1998), as corrected on July 20, 1998 
(63 FR 38742). Copies may be obtained from Bell Helicopter Textron, 
Inc., P.O. Box 482, Fort Worth, Texas 76101, telephone (817) 280-
3391, fax (817) 280-6466; or Agusta, 21017 Cascina Costa di Samarate 
(VA), Via Giovanni Agusta 520, telephone (0331) 229111, fax (0331) 
229605-222595. Copies may be inspected at the FAA, Office of the 
Regional Counsel, Southwest Region, 2601 Meacham Blvd., Room 663, 
Fort Worth, Texas; or at the Office of the Federal Register, 800 
North Capitol Street, NW., suite 700, Washington, DC.
    (h) This amendment becomes effective on June 11, 2001.

    Note 3: The subject of this AD is addressed in Registro 
Aeronautico Italiano (Italy) AD 97-223, dated August 1, 1997.


    Issued in Fort Worth, Texas, on April 20, 2001.
Larry M. Kelly,
Acting Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. 01-10731 Filed 5-4-01; 8:45 am]
BILLING CODE 4910-13-U

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