[Federal Register Volume 66, Number 12 (Thursday, January 18, 2001)]
[Rules and Regulations]
[Pages 4654-4655]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 01-1121]


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

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2000-SW-52-AD; Amendment 39-12074; AD 2001-01-04]
RIN 2120-AA64


Airworthiness Directives; Sikorsky Aircraft Corporation Model S-
76A, S-76B, and S-76C Helicopters

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule; request for comments.

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

SUMMARY: This amendment adopts a new airworthiness directive (AD) for 
Sikorsky Aircraft Corporation (Sikorsky) Model S-76A, S-76B, and S-76C 
helicopters. This AD requires initial and repetitive inspections of the 
main landing gear positioning rod assembly (rod assembly) and the side 
brace rod end (rod end) for corrosion. If any corrosion is found, this 
AD requires replacing any part that is corroded with an airworthy part 
before further flight. This amendment is prompted by a landing gear 
collapse caused by corrosion due to dissimilar metals in the landing 
gear rod end. The actions specified in this AD are intended to detect 
corrosion of the threaded joint in the rod assembly to prevent a 
collapse of the landing gear, and subsequent loss of control of the 
helicopter during landing.

DATES: Effective February 2, 2001.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of February 2, 2001.
    Comments for inclusion in the Rules Docket must be received on or 
before March 19, 2001.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Office of the Regional Counsel, Southwest Region, 
Attention: Rules Docket No. 2000-SW-52-AD, 2601 Meacham Blvd., Room 
663, Fort Worth, Texas 76137. You may also send comments electronically 
to the Rules Docket at the following address: [email protected].
    The service information referenced in this AD may be obtained from 
BF Goodrich Landing Gear Division, Attn.: Kenneth R. Madej, 8000 Marble 
Ave., Cleveland, OH 44105, telephone (216) 429-4461, fax (216) 429-
4357. 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: Jeffrey Lee, Aviation Safety Engineer, 
Boston Aircraft Certification Office, 12 New England Executive Park, 
Burlington, MA 01803, telephone (781) 238-7161, fax (781) 238-7199.

SUPPLEMENTARY INFORMATION: This amendment adopts a new AD for Sikorsky 
Model S-76A, S-76B, and S-76C helicopters. This AD requires, within 14 
days, inspecting the rod assembly, part number (P/N) 1945E-31A or 2071-
31, and rod end, P/N 1945E235 or 2071-235, for corrosion. If the rod 
assembly and rod end were inspected and reassembled in accordance with 
BF Goodrich Component Maintenance Manual with Illustrated Parts List, 
1945/2071 Series Main Landing Gear, No. 32-10-01, (formerly titled 
Cleveland Pneumatic Maintenance Manual 32-10-01), Revision 4, dated 
December 15, 1994, within the past 24 months, this AD requires an 
inspection within 90 days. If any corrosion is found, this AD requires 
replacing the unairworthy part with an airworthy part before further 
flight. This AD also requires, at intervals not to exceed 90 days, a 
repetitive inspection for corrosion on certain rod ends. For other rod 
ends, this AD requires a repetitive inspection for corrosion at 
intervals not to exceed 12 months or 1,500 hours time-in-service, 
whichever occurs first. This AD is prompted by a landing gear collapse 
on a helicopter that was in a hangar. Analysis showed that corrosion 
due to dissimilar metals in the rod end caused the rod end to fail with 
subsequent collapse of the landing gear. The actions specified in this 
AD are intended to detect corrosion of the threaded joint in the rod 
assembly and prevent a collapse of the landing gear and subsequent loss 
of control of the helicopter during landing.
    The FAA has reviewed BF Goodrich Landing Gear Service Bulletin No. 
76A-32-03, Revision 1, dated September 15, 2000, which describes 
procedures for inspecting and repairing or replacing the rod end and 
rod assembly.
    Since an unsafe condition has been identified that is likely to 
exist or develop on other Sikorsky Model S-76A, S-76B, and S-76C 
helicopters of the same type design, this AD is being issued to detect 
corrosion of the threaded joint in the rod assembly and prevent a 
collapse of the landing gear. This AD requires inspecting the rod 
assembly and rod end for corrosion at specified intervals and 
replacing, before further flight, any component that has corrosion. The 
actions must be accomplished in accordance with the service bulletin 
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, 
the actions previously mentioned are required within 14 days, 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 180 helicopters will be affected by this AD 
and that it will take approximately 4.5 work hours per helicopter to 
inspect the rod assembly and rod end and 1.5 work hours to remove and 
replace the rod assembly and rod end, if necessary. Required parts will 
cost approximately $14,600 per helicopter. Based on these figures, the 
total cost impact of the AD on U.S. operators is estimated to be 
$2,692,800 ($14,960 per helicopter, assuming inspecting, removing, and 
replacing the rod assembly and rod end once).

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

[[Page 4655]]

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. 2000-SW-52-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 
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 adding a new airworthiness directive 
to read as follows:

2001-01-04 Sikorsky Aircraft Corporation: Amendment 39-12074. Docket 
No. 2000-SW-52-AD.
    Applicability: Model S-76A, S-76B, and S-76C helicopters up to 
and including serial number 760513 with positioning rod assembly 
(rod assembly), part number (P/N) 1945E-31A or 2071-31, or side 
brace rod end (rod end), P/N 1945E-235 or 2071-235, 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 detect corrosion of the threaded joint in the rod assembly 
and prevent a collapse of the landing gear and subsequent loss of 
control of the helicopter during landing, accomplish the following:
    (a) Within 14 days, inspect the rod assembly and rod end for 
corrosion in accordance with Section 2., Accomplishment 
Instructions, in BF Goodrich Service Bulletin No. 76A-32-03, 
Revision 1, dated September 15, 2000 (SB), except that scrapping of 
corroded parts is not required. Replace any part that is corroded 
with an airworthy part before further flight.
    (b) Within 90 days, if the rod assembly and rod end were 
inspected and reassembled in accordance with BF Goodrich Component 
Maintenance Manual with Illustrated Parts List, 1945/2071 Series 
Main Landing Gear, No. 32-10-01, (formerly titled Cleveland 
Pneumatic Maintenance Manual 32-10-01), Revision 4, dated December 
15, 1994, within the past 24 months, inspect the rod assembly and 
rod end in accordance with Section 2. of the SB. Scrapping of 
corroded parts is not required. Replace any part that is corroded 
with an airworthy part before further flight.
    (c) At intervals not to exceed 90 days, for rod ends that are 
not reassembled with Mastinox sealant or reassembled with Mastinox 
sealant but without cadmium plate restoration, inspect the rod 
assembly and rod end for corrosion in accordance with the Section 2. 
of the SB, except that scrapping of corroded parts is not required. 
Replace any part that is corroded with an airworthy part before 
further flight.
    (d) At intervals not to exceed 12 months or 1,500 hours time-in-
service, whichever occurs first, for rod ends assembled with 
Mastinox sealant and cadmium plate restoration or for rod ends 
reassembled with Mastinox but that did not previously require rework 
due to corrosion, inspect the rod assembly and rod end for corrosion 
in accordance with the Section 2. of the SB, except that scrapping 
of corroded parts is not required. Replace any part that is corroded 
with an airworthy part 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, Boston Aircraft Certification 
Office (ACO), 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 ACO.

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

    (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 to a location where the 
requirements of this AD can be accomplished.
    (g) The inspections shall be done in accordance with Section 2., 
Accomplishment Instructions, in BF Goodrich Service Bulletin No. 
76A-32-03, Revision 1, dated September 15, 2000. 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 BF Goodrich Landing Gear Division, Attn.: Kenneth R. 
Madej, 8000 Marble Ave., Cleveland, OH 44105, telephone (216) 429-
4461, fax (216) 429-4357. 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 February 2, 2001.

    Issued in Fort Worth, Texas, on January 5, 2001.
Henry A. Armstrong,
Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. 01-1121 Filed 1-17-01; 8:45 am]
BILLING CODE 4910-13-U