[Federal Register Volume 59, Number 184 (Friday, September 23, 1994)]
[Unknown Section]
[Page 0]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 94-23441]


[[Page Unknown]]

[Federal Register: September 23, 1994]


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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39

[Docket No. 94-SW-07-AD; Amendment 39-9031; AD 94-20-03]

 

Airworthiness Directives; Bell Helicopter Textron, Inc. Model 
206A, 206B, 206B-1, 206L, 206L-1, 206L-3, and 206L-4 Helicopters

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule; request for comments.

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SUMMARY: This amendment supersedes an existing airworthiness directive 
(AD) applicable to Bell Helicopter Textron, Inc. (BHTI) Model 206A, 
206B, 206B-1, 206L, 206L-1, 206L-3, and 206L-4 helicopters, that 
currently requires an inspection of the main rotor hub trunnion 
(trunnion) for a mislocated master spline and replacement of any 
trunnion that has a mislocated master spline. This amendment is 
prompted by a report that certain main rotor hub trunnions (trunnions) 
were manufactured with a mislocated master spline. The actions 
specified by this AD are intended to identify and require replacement 
of any trunnion with a mislocated master spline to prevent pitch link 
misalignment, altered cyclic stick control position, loss of the main 
rotor system, and subsequent loss of control of the helicopter.

DATES: Effective October 11, 1994.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of October 11, 1994.
    Comments for inclusion in the Rules Docket must be received on or 
before November 7, 1994.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Office of the Assistant Chief Counsel, Attention: 
Rules Docket No. 94-SW-07-AD, 2601 Meacham Boulevard, Room 663, Fort 
Worth, Texas 76137-4298.
    The service information referenced in this AD may be obtained from 
Bell Helicopter Textron, Inc., P.O. Box 482, Fort Worth, Texas 76101. 
This information may be examined at the FAA, Office of the Assistant 
Chief Counsel, 2601 Meacham Boulevard, 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:
Ms. Sharon Miles, Aerospace Engineer, Rotorcraft Certification Office, 
FAA, Southwest Region, Rotorcraft Directorate, 2601 Meacham Boulevard, 
Fort Worth, Texas 76137-4298, telephone (817) 222-5172, fax (817) 222-
5959.

SUPPLEMENTARY INFORMATION: On November 18, 1993, the FAA issued 
Priority Letter AD 93-22-11, applicable to Bell Helicopter Textron, 
Inc. (BHTI) Model 206A, 206B, 206B-1, 206L, 206L-1, 206L-3, and 206L-4 
helicopters, to require an inspection of the main rotor hub trunnion 
(trunnion), part number (P/N) 206-011-113-103 and P/N 206-011-120-103, 
for proper positioning of the trunnion master spline and replacement of 
any trunnion that had a mislocated master spline. That action was 
prompted by a manufacturer's report that certain trunnions were 
manufactured with a mislocated master spline. The manufacturer's data 
showed that when the trunnion master spline is mislocated, the main 
rotor mast does not align properly, so the operator's input to the 
cyclic stick does not produce the desired result in the main rotor 
system. After reviewing the manufacturer's data, the FAA determined 
that any mislocated trunnion master spline creates an unsafe condition. 
This condition, if not corrected, could result in pitch link 
misalignment, altered cyclic stick control position, loss of the main 
rotor system, and subsequent loss of control of the helicopter.
    Since the issuance of that AD, BHTI has issued a revised Alert 
Service Bulletin (ASB) for Model 206L, 206L-1, 206L-3, and 206L-4 
helicopters. ASB 206L-93-90, Revision A, dated November 9, 1993, 
changed Figure 3 to show that the center line of the trunnion should go 
through the crown rather than the inset of the master spline. ASB 206-
93-75, dated October 19, 1993, which is applicable to Model 206A, 206B, 
and 206B-1 helicopters, has a correct Figure 3 showing that the center 
line of the trunnion should go through the inset rather than the crown 
of the master spline.
    Since an unsafe condition has been identified that is likely to 
exist or develop on other BHTI Model 206 helicopters of this same type 
design, this AD supersedes Priority Letter AD 93-22-11 to require, 
within the next 50 hours time-in-service (TIS) or 90 calendar days 
after the effective date of this AD, whichever occurs first, an 
inspection of the trunnion for proper positioning of the trunnion 
master spline, and replacement of any trunnion that has a mislocated 
master spline. The actions are required to be accomplished in 
accordance with the BHTI ASB 206-93-75, dated October 19, 1993, for 
Model 206A, 206B, and 206B-1 helicopters, and BHTI ASB 206L-93-90, 
Revision A, dated November 9, 1993, for Model 206L, 206L-1, 206L-3, and 
206L-4 helicopters, described previously. Due to the criticalness of 
correct alignment of the trunnion master spline and a compliance time 
that is short for some operators of frequently-used helicopters, this 
rule must be issued immediately to correct an unsafe condition in 
aircraft.
    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 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 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 Number 94-SW-07-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, 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. App. 1354(a), 1421 and 1423; 49 U.S.C. 
106(g); and 14 CFR 11.89.


Sec. 39.13  [Amended]

    2. Section 39.13 is amended by adding a new airworthiness directive 
(AD), Amendment 39-9031, to read as follows:

AD 94-20-03 Bell Helicopter Textron, Inc., (BHTI): Amendment 39-
9031. Docket Number 94-SW-07-AD. Supersedes Priority Letter AD 93-
22-11, issued November 18, 1993.

    Applicability: Model 206A, 206B, 206B-1, 206L, 206L-1, 206L-3, 
and 206L-4 helicopters, equipped with main rotor hub trunnion 
(trunnion), part number (P/N) 206-011-113-103 or P/N 206-011-120-
103, certificated in any category.
    Compliance: Required as indicated, unless accomplished 
previously.
    To prevent pitch link misalignment, altered cyclic stick control 
position, loss of the main rotor system, and subsequent loss of 
control of the helicopter, accomplish the following:
    (a) Within the next 50 hours time-in-service (TIS) or 90 
calendar days after the effective date of this airworthiness 
directive (AD), whichever occurs first, inspect the trunnion master 
spline for proper positioning in accordance with Parts I and II of 
the Accomplishment Instructions contained in BHTI Alert Service 
Bulletin 206-93-75, dated October 19, 1993, for Model 206A, 206B, 
and 206B-1 helicopters, and BHTI Alert Service Bulletin 206L-93-90, 
Revision A, dated November 9, 1993, for Model 206L, 206L-1, 206L-3, 
and 206L-4 helicopters.
    (b) If the master spline is not in the proper position, before 
further flight remove and replace the trunnion with an airworthy 
trunnion in accordance with the provisions of the applicable 
maintenance manual.
    (c) An alternative method of compliance or adjustment of the 
compliance time that provides an acceptable level of safety may be 
used when 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: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Rotorcraft Certification Office.

    (d) Special flight permits may be issued in accordance with 
Sec. Sec. 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 provided there is no 
interference between the pitch link clevices and the swashplate 
outer ring or pitch horn lugs, through full motion of the cyclic and 
collective controls.
    (e) The inspection and replacement, if necessary, shall be done 
in accordance with BHTI Alert Service Bulletin No. 206-93-75, dated 
October 19, 1993, and Alert Service Bulletin No. 206L-93-90, 
Revision A, dated November 9, 1993. 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 
Bell Helicopter Textron, Inc., P.O. Box 482, Fort Worth, Texas 
76101. Copies may be inspected at the FAA, Office of the Assistant 
Chief Counsel, 2601 Meacham Boulevard, Room 663, Fort Worth, Texas; 
or at the Office of the Federal Register, 800 North Capitol Street, 
NW., suite 700, Washington, DC.
    (f) This amendment becomes effective on October 11, 1994.

    Issued in Fort Worth, Texas, on September 16, 1994.
Larry M. Kelly,
Acting Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. 94-23441 Filed 9-22-94; 8:45 am]
BILLING CODE 4910-13-P