AD 2000-05-16
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Sikorsky | S-61 | Airworthiness Directives; Sikorsky Model S-61 Helicopters |
Unsafe Condition
Extensive cracking in the area of the pylon upper and lower hinge web fittings, which could lead to structural failure of the tail boom 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
Inspect certain pylon upper and lower hinge web fittings for corrosion or cracks. Repair or replace unairworthy web fittings with airworthy ones. Create a log card or equivalent record and implement a recurring inspection of the web fittings.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Before further flight.
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
Sikorsky Model S-61 helicopters.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
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.
Document Text
Show stored source text (verify against official source)
[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 [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[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
Source: Official FAA Source ↗
Retrieved: Apr 6, 2026
Rights: U.S. Government Public Domain
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