Airworthiness Directives; Sikorsky Model S-61 Helicopters

[Federal Register Volume 65, Number 51 (Wednesday, March 15, 2000)]
[Rules and Regulations]
[Pages 13877-13879]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 00-6036]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 99-SW-61-AD; Amendment 39-11626; AD 2000-05-16]
RIN 2120-AA64


Airworthiness Directives; Sikorsky Model S-61 Helicopters

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule; request for comments.

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SUMMARY: This amendment adopts a new airworthiness directive (AD) 
applicable to Sikorsky Model S-61 helicopters. This action requires 
inspecting certain pylon upper and lower hinge web fittings (web 
fittings) for corrosion or a crack and either repairing certain web 
fittings or replacing any unairworthy web fittings with airworthy web 
fittings. The AD also requires creating a log card or equivalent record 
and implementing a recurring inspection of the web fittings. This 
amendment is prompted by the discovery of extensive cracking in the 
area of the web fittings. The actions specified in this AD are intended 
to prevent structural failure of the tail boom due to a crack or 
corrosion of certain web fittings and subsequent loss of control of the 
helicopter.

DATES: Effective March 30, 2000.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of March 30, 2000.
    Comments for inclusion in the Rules Docket must be received on or 
before May 15, 2000.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Office of the Regional Counsel, Southwest Region, 
Attention: Rules Docket No. 99-SW-61-AD, 2601 Meacham Blvd., Room 663, 
Fort Worth, Texas 76137.
    The service information referenced in this AD may be obtained from 
Sikorsky Aircraft Corporation, Attn: Manager, Commercial Tech Support, 
6900 Main Street, P. O. Box 9729, Stratford, Connecticut 06497-9129, 
phone (203) 386-7860, fax (203) 386-4703. This information may be 
examined at the FAA, Office of the Regional Counsel, Southwest Region, 
2601 Meacham Blvd., Room 663, Fort Worth, Texas 76137; or at the Office 
of the Federal Register, 800 North Capitol Street, NW., suite 700, 
Washington, DC.

FOR FURTHER INFORMATION CONTACT: Brian K. Murphy, Aerospace Engineer, 
ANE-150, 12 New England Executive Park, Burlington, MA 01803, telephone 
(781) 238-7739, fax (781) 238-7199.

SUPPLEMENTARY INFORMATION: This amendment adopts a new AD applicable to 
Sikorsky Model S-61 helicopters with pylon, part number, (P/N) S6120-
76265-001 or S6120-76266-507, installed. The AD requires inspecting and 
repairing or, if necessary, replacing certain web fittings and the 
fitting faying surfaces. The AD also requires making an entry on the 
log card or equivalent record.
    This amendment is prompted by the discovery of extensive cracking 
in the area of the web fitting. The actions specified in this AD are 
intended to prevent structural failure of certain web fittings due to 
stress corrosion and subsequent structural failure of the tailboom. 
This condition, if not corrected, could result in loss of control of 
the helicopter.
    The FAA has reviewed Sikorsky Aircraft Corporation Alert Service 
Bulletin No. 61B20-33, dated September 3, 1999 (ASB), which describes 
procedures for inspecting and repairing or, if necessary, replacing 
certain web fittings having a crack or corrosion.
    Since an unsafe condition has been identified that is likely to 
exist or develop on other Sikorsky Model S61 helicopters of the same 
type design, this AD is being issued to prevent structural failure of 
certain web fittings due to a crack or corrosion. This AD requires

[[Page 13878]]

inspecting and repairing or replacing the web fittings as necessary. 
The actions are required to be accomplished in accordance with the ASB 
described previously. The short compliance time involved is required 
because the previously described critical unsafe condition can 
adversely affect the structural integrity of the helicopter. Therefore, 
inspecting for a crack or corrosion in the web fittings and repairing 
or replacing, if necessary, an unairworthy web fitting with an 
airworthy web fitting is required prior to further flight and this AD 
must be issued immediately.
    Since a situation exists that requires the immediate adoption of 
this regulation, it is found that notice and opportunity for prior 
public comment hereon are impracticable, and that good cause exists for 
making this amendment effective in less than 30 days.
    The FAA estimates that 125 helicopters will be affected by this AD, 
that it will take approximately 115 work hours to accomplish the 
inspection and replacement of parts, and that the average labor rate is 
$60 per work hour. Required parts will cost approximately $75,000 per 
helicopter. Based on these figures, the total cost impact of the AD on 
U.S. operators is estimated to be $10,237,500 if the parts have to be 
replaced on the entire fleet.

Comments Invited

    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, both before and after the closing date for comments, 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 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. 99-SW-61-AD.'' The postcard will be date stamped and 
returned to the commenter.
    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, 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 
location provided under the caption ADDRESSES.

List of Subjects 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 adding a new airworthiness directive 
to read as follows:

AD 2000-05-16  Sikorsky Aircraft Corporation: Amendment 39-11626. 
Docket No. 99-SW-61-AD.

    Applicability: Model S-61 helicopters with pylon, part number 
(P/N) S6120-76265-001 or S6120-76266-507, 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 (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 as indicated, unless accomplished 
previously.
    To prevent structural failure due to a crack or corrosion of 
pylon upper and lower hinge web fittings (web fittings), P/N S6120-
76261-012, -013 (upper) or S6120-76262-012, -013 (lower), and 
subsequent loss of control of the helicopter, accomplish the 
following:
    (a) Within 25 hours time-in-service (TIS),
    (1) Determine the alloy-temper of the web fittings in accordance 
with Sikorsky Aircraft Corporation Alert Service Bulletin No. 61B20-
33, dated September 3, 1999 (ASB), Accomplishment Instructions, 
paragraph 3.A.
    (2) Prepare the web fittings for inspection in accordance with 
the ASB Accomplishment Instructions, paragraph 3.B.
    (3) Inspect the web fitting in accordance with the ASB 
Inspection Plan, Chart A, and the Accomplishment Instructions, 
paragraphs 3.C., 3.D, and 3.E. Nicks, scratches, corrosion pitting 
or prior rework beyond the limits specified in paragraph 3.C.(5) 
require approval by the FAA.
    (4) Repair or replace web fittings, as necessary, in accordance 
with the ASB Accomplishment Instructions, paragraph 3.C.(3) through 
(6). Nicks, scratches, corrosion pitting, or prior rework beyond the 
limits specified in paragraph 3.C.(5) require approval by the FAA.
    (5) If replacing an unairworthy web fitting with an airworthy 
web fitting, replace it in accordance with the ASB Accomplishment 
Instructions, paragraph 3.F., prior to further flight.
    (6) Create a log card for the pylon, if none exists. Make an 
entry on the log card or equivalent record implementing recurring 
inspection intervals in accordance with Chart A of the ASB.
    (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, Boston 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, Boston Aircraft Certification Office.


[[Page 13879]]


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

    (c) 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 to a location where the 
requirements of this AD can be accomplished.
    (d) The inspection, repair, and replacement shall be done in 
accordance with the Inspection Plan, Chart A, and the Accomplishment 
Instructions of Sikorsky Aircraft Corporation Alert Service Bulletin 
No. 61B20-33, dated September 3, 1999. This incorporation by 
reference was approved by the Director of the Federal Register in 
accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be 
obtained from Sikorsky Aircraft Corporation, Attn: Manager, 
Commercial Tech Support, 6900 Main Street, P. O. Box 9729, 
Stratford, Connecticut 06497-9129, phone (203) 386-7860, fax (203) 
386-4703. 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.
    (e) This amendment becomes effective on March 30, 2000.

    Issued in Fort Worth, Texas, on March 6, 2000.
Henry A. Armstrong,
Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. 00-6036 Filed 3-14-00; 8:45 am]
BILLING CODE 4910-13-U

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