[Federal Register Volume 64, Number 82 (Thursday, April 29, 1999)]
[Rules and Regulations]
[Pages 23016-23017]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-10669]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98-SW-49-AD; Amendment 39-11153; AD 99-09-20]
RIN 2120-AA64


Airworthiness Directives; Bell Helicopter Textron Canada (BHTC) 
Model 222, 222B, and 222U 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) that 
is applicable to BHTC Model 222, 222B, and 222U helicopters. This 
action requires initial and repetitive visual inspections and 
verification of the torque of the bolts on the main rotor hub. This 
amendment is prompted by a report of fatigue cracks around the bolt 
holes of the main rotor pitch horn (pitch horn) and a cracked main 
rotor flapping bearing assembly (flapping bearing assembly) on a BHTC 
Model 222 helicopter. This condition, if not corrected, could result in 
fretting-induced fatigue cracking of the flapping bearing assembly and 
around the bolt holes of the pitch horn, loss of the rotor system, and 
subsequent loss of control of the helicopter.

DATES: Effective May 14, 1999.
    Comments for inclusion in the Rules Docket must be received on or 
before June 28, 1999.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Office of the Regional Counsel, Southwest Region, 
Attention: Rules Docket No. 98-SW-49-AD, 2601 Meacham Blvd., Room 663, 
Fort Worth, Texas 76137.

FOR FURTHER INFORMATION CONTACT: Harry Edmiston, Aerospace Engineer, 
Rotorcraft Certification Office, Rotorcraft Directorate, FAA, 2601 
Meacham Blvd., Fort Worth, Texas 76137, telephone (817) 222-5158, fax 
(817) 222-5783.

SUPPLEMENTARY INFORMATION: Transport Canada, which is the airworthiness 
authority for Canada, has notified the FAA that an unsafe condition may 
exist on BHTC Model 222, 222B, and 222U helicopters. Transport Canada 
advises that fatigue cracks at the bolt holes of the pitch horn and in 
the flapping bearing assembly can lead to loss of control of the 
helicopter.
    BHTC issued Alert Service Bulletin Nos. 222-98-81 and 222U-98-52, 
both dated April 23, 1998 (ASB), which specify inspecting the main 
rotor hub in the areas between the pitch horn and main rotor grip tangs 
(grip tangs) and between the flapping bearing assembly and the main 
rotor yoke assembly for fretting. The ASB's also specify torque 
verification procedures for the main rotor grip retaining bolts and the 
flapping bearing assembly. Transport Canada classified these ASB's as 
mandatory and issued Transport Canada AD CF-98-16, dated July 15, 1998, 
in order to assure the continued airworthiness of these helicopters in 
Canada.
    These helicopter models are manufactured in Canada and are type 
certificated for operation in the United States under the provisions of 
Sec. 21.29 of the Federal Aviation Regulations (14 CFR 21.29) and the 
applicable bilateral airworthiness agreement. Pursuant to this 
bilateral airworthiness agreement, Transport Canada has kept the FAA 
informed of the situation described above. The FAA has examined the 
findings of Transport Canada, 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 FAA estimates that 88 helicopters will be affected by this 
proposed AD, that it will take approximately 1 work hour to accomplish 
the inspection and retorque of bolts, if necessary, and that the 
average labor rate is $60 per work hour. Based on these figures, the 
total cost impact of the AD on U.S. operators is estimated to be 
$15,840 per year, assuming three inspections and retorques per year and 
assuming that no parts will need to be replaced.
    Since an unsafe condition has been identified that is likely to 
exist or develop on other BHTC Model 222, 222B, and 222U helicopters of 
the same type design registered in the United States, this AD is being 
issued to prevent fretting induced fatigue cracking of the flapping 
bearing assembly and around the bolt holes of the pitch horn, loss of 
the rotor system, and subsequent loss of control of the helicopter. 
This AD requires recurring inspections of the main rotor hub in the 
areas between the pitch horn and grip tangs and between the flapping 
bearing assembly and the main rotor yoke assembly for fretting. If 
fretting is found on any part, replacing that part with an airworthy 
part is required. This AD also requires verifying the torque on the 
main rotor grip retaining bolts and the flapping bearing assembly 
retaining bolts. The short compliance time involved is required because 
the previously described critical unsafe condition can adversely affect 
the controllability of the helicopter. Therefore, a visual inspection 
of the main rotor hub between the pitch horn and grip tangs and the 
flapping bearing assembly and the main rotor yoke assembly for fretting 
is required. A torque check of the main rotor grip retaining bolts and 
the flapping bearing assembly retaining bolts is also required. These 
actions are required within 10 hours TIS 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.
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

[[Page 23017]]

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. 98-SW-49-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, in 
accordance with Executive Order 12612, it is determined that this final 
rule does not have sufficient federalism implications to warrant the 
preparation of a Federalism Assessment.
    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, 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:

99-09-20  Bell Helicopter Textron Canada: Amendment 39-11153. Docket 
No. 98-SW-49-AD.

    Applicability: Model 222 helicopters, serial numbers (S/N) 47006 
through 47089, Model 222B helicopters, S/N's 47131 through 47156, 
and Model 222U helicopters, S/N's 47501 through 47574, 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 fretting induced fatigue cracking of the main rotor 
flapping bearing assembly (flapping bearing assembly) and around the 
bolt holes of the main rotor pitch horn (pitch horn), loss of the 
rotor system, and subsequent loss of control of the helicopter, 
accomplish the following:
    (a) Within 10 hours time-in-service (TIS), and thereafter at 
intervals not to exceed 150 hours TIS:
    (1) Perform a visual inspection of the main rotor hub for 
fretting between the pitch horn and main rotor grip tangs (grip 
tangs) and between the flapping bearing assembly and the main rotor 
yoke assembly. If fretting is found on any part, replace it with an 
airworthy part.
    (2) Verify the torque of the main rotor grip retaining bolts and 
the flapping bearing assembly bolts in the tightening direction, 
minimum 100 foot-pounds. If 100 foot-pounds torque is reached 
without movement of the bolts, torque bolts to 125 foot-pounds.
    (3) If any bolt moves before 100 foot-pounds torque is reached, 
remove the pitch horn or the flapping bearing assembly, as 
applicable, from the main rotor hub assembly for further inspection. 
Inspect the pitch horn or flapping bearing assembly, as applicable, 
and all faying surfaces of the pitch horn, flapping bearing 
assembly, buffers, main rotor yoke assembly, and the grip tangs for 
fretting. If fretting is found on any part, replace it with an 
airworthy part.
    (4) Apply corrosion preventive compound to the exposed portions 
of the bolts and nuts.

    Note 2: Bell Helicopter Textron Alert Service Bulletin Nos. 222-
98-81 and 222U-98-52, both dated April 23, 1998, 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, Rotorcraft Certification Office, 
FAA, Rotorcraft Directorate. Operators shall submit their requests 
through an FAA Principal Maintenance Inspector, who may concur or 
comment and then send it to the Manager, Rotorcraft Certification 
Office.

    Note 3: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Rotorcraft Certification Office.

    (c) Special flight permits may be issued in accordance with 
sections 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) This amendment becomes effective on May 14, 1999.

    Note 3: The subject of this AD is addressed in Transport Canada 
(Canada) AD CF-98-16, dated July 15, 1998.

    Issued in Fort Worth, Texas, on April 22, 1999.
Henry A. Armstrong,
Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. 99-10669 Filed 4-28-99; 8:45 am]
BILLING CODE 4910-13-P