[Federal Register Volume 63, Number 69 (Friday, April 10, 1998)]
[Rules and Regulations]
[Pages 17677-17679]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-9478]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98-SW-08-AD; Amendment 39-10461; AD 98-04-12]
RIN 2120-AA64


Airworthiness Directives; Robinson Helicopter Company Model R44 
Helicopters

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule; request for comments.

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SUMMARY: This document publishes in the Federal Register an amendment 
adopting Airworthiness Directive (AD) 98-04-12 which was sent 
previously to all known U.S. owners and operators of Robinson 
Helicopter Company (RHC)

[[Page 17678]]

Model R44 helicopters by individual letters. This AD requires an 
initial and repetitive measurement of the lateral cyclic trim spring 
shaft (shaft) diameter and replacement of the shaft spring assembly 
(spring assembly) if the shaft diameter is excessively worn. 
Replacement of the spring assembly with a modified spring assembly is 
considered terminating action for this AD. This amendment is prompted 
by an incident in which a pilot felt binding in the cyclic control when 
attempting to move it to the left. A precautionary landing was made 
using only right-hand turns. Subsequent inspection revealed that a 
notch was worn in the shaft, which caused the shaft and spring to move 
from the lower mount and interfere with the lateral control. Inspection 
of a second RHC Model 44 helicopter revealed similar wear. Excessive 
wear can create a notch on the shaft, which can cause the spring 
assembly to move out of its lower mount. This condition, if not 
corrected, could lead to the shaft interfering with lateral cyclic 
control, which could result in loss of control of the helicopter.

DATES: Effective April 27, 1998, to all persons except those persons to 
whom it was made immediately effective by priority letter AD 98-04-12, 
issued on February 4, 1998, which contained the requirements of this 
amendment.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of April 27, 1998.
    Comments for inclusion in the Rules Docket must be received on or 
before June 9, 1998.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Office of the Regional Counsel, Southwest Region, 
Attention: Rules Docket No. 98-SW-08-AD, 2601 Meacham Blvd., Room 663, 
Fort Worth, Texas 76137.
    The applicable service information may be obtained from Robinson 
Helicopter Company, 2901 Airport Drive, Torrance, California 90505 
telephone (310) 539-0508, fax (310) 539-5198. 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: Mr. Fredrick A. Guerin, Aerospace 
Engineer, FAA, Los Angeles Aircraft Certification Office, 3960 
Paramount Blvd., Lakewood, California 90712, telephone (562)-627-5232, 
fax (562)-627-5210.

SUPPLEMENTARY INFORMATION: On February 4, 1998, the FAA issued priority 
letter AD 98-04-12, applicable to RHC Model R44 helicopters, which 
requires an initial and repetitive measurement of the shaft diameter, 
and replacement of the spring assembly if the shaft diameter is 
excessively worn. That action was prompted by an incident in which a 
pilot felt binding in the cyclic control when attempting to move it to 
the left. A precautionary landing was made using only right-hand turns. 
Subsequent inspection revealed that a notch was worn in the shaft, 
which caused the shaft and spring to move from the lower mount and 
interfere with the lateral control. Inspection of a second RHC Model 44 
helicopter revealed similar wear. Excessive wear can create a notch on 
the shaft, which can cause the spring assembly to move out of its lower 
mount. This condition, if not corrected, could lead to the shaft 
interfering with lateral cyclic control, which could result in loss of 
control of the helicopter.
    The FAA has reviewed Robinson Helicopter Company R44 Service 
Bulletin SB-26, dated January 31, 1998, which describes procedures for 
measurement of the shaft diameter, and replacing the spring assembly 
with a modified spring assembly if the shaft diameter varies more than 
0.004 inch in any 0.50 inch of length.
    Since the unsafe condition described is likely to exist or develop 
on other RHC Model R44 helicopters of the same type design, the FAA 
issued priority letter AD 98-04-12 to prevent the shaft from 
interfering with lateral cyclic control, which could result in loss of 
control of the helicopter. The AD requires, within 10 hours time-in-
service (TIS) after the effective date of this AD, and thereafter at 
intervals not to exceed 20 hours TIS until replacement of the spring 
assembly with a modified spring assembly is accomplished, a measurement 
of the shaft diameter; and replacement of the C056-1 Rev. A through G 
spring assembly with a C056-1 Rev. H spring assembly if the shaft 
diameter measurement varies more than 0.004 inch in any 0.50 inch of 
length. Replacement of the C056-1 Rev. A through G spring assembly with 
a C056-1 Rev. H spring assembly is considered terminating action for 
the requirements of this AD. The actions are required to be 
accomplished in accordance with the service bulletin described 
previously.
    Since it was found that immediate corrective action was required, 
notice and opportunity for prior public comment thereon were 
impracticable and contrary to the public interest, and good cause 
existed to make the AD effective immediately by individual letters 
issued on February 4, 1998 to all known U.S. owners and operators of 
RHC Model R44 helicopters. These conditions still exist, and the AD is 
hereby published in the Federal Register as an amendment to section 
39.13 of the Federal Aviation Regulations (14 CFR 39.13) to make it 
effective to all persons.

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. 98-SW-08-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

[[Page 17679]]

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. 106(g), 40113, 44701.


Sec. 39.13  [Amended]

    2. Section 39.13 is amended by adding a new airworthiness directive 
to read as follows:

98-04-12  Robinson Helicopter Company: Amendment 39-10461. Docket 
No. 98-SW-08-AD.

    Applicability: Model R44 helicopters, serial numbers 0002 
through 0420, 0425, 0426, and 0427, with a C056-1 Rev. A through G 
spring assembly 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 
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 use the authority 
provided in paragraph (d) to request approval from the FAA. This 
approval may address either no action, if the current configuration 
eliminates the unsafe condition, or different actions necessary to 
address the unsafe condition described in this AD. Such a request 
should include an assessment of the effect of the changed 
configuration on the unsafe condition addressed by this AD. In no 
case does the presence of any modification, alteration, or repair 
remove any helicopter from the applicability of this AD.

    Compliance: Required as indicated, unless accomplished 
previously.
    To detect excessive wear on the lateral cyclic trim spring shaft 
(shaft), which could allow the shaft to move from its lower mount 
and interfere with lateral cyclic control resulting in loss of 
control of the helicopter, accomplish the following:
    (a) Within 10 hours time-in-service (TIS), and thereafter at 
intervals not to exceed 20 hours TIS, measure the diameter of the 
shaft in accordance with the Compliance Procedure contained in 
Robinson Helicopter Company R44 Service Bulletin SB-26, dated 
January 31, 1998 (SB-26).
    (b) If the shaft diameter varies more than 0.004 inch in any 
0.50 inch of length, in the measurement area shown in Figure 1 of 
SB-26, replace the C056-1 Rev. A through G spring assembly with a 
C056-1 Rev. H spring assembly before further flight.
    (c) Replacing the C056-1 Rev. A through G spring assembly with a 
C056-1 Rev. H spring assembly in accordance with the service 
bulletin is considered terminating action for the requirements of 
this AD.
    (d) 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, Los Angeles 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, Los Angeles Aircraft Certification Office.

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

    (e) Special flight permits will not be issued.
    (f) The inspection shall be done in accordance with the 
Compliance Procedure contained in Robinson Helicopter Company R44 
Service Bulletin SB-26, dated January 31, 1998. 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 Robinson Helicopter Company, 2901 Airport Drive, 
Torrance, California 90505, telephone (310) 539-0508, fax (310) 539-
5198. 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.
    (g) This amendment becomes effective on April 27, 1998, to all 
persons except those persons to whom it was made immediately 
effective by Priority Letter AD 98-04-12, issued February 4, 1998, 
which contained the requirements of this amendment.

    Issued in Fort Worth, Texas, on April 3, 1998.
Henry A. Armstrong,
Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. 98-9478 Filed 4-9-98; 8:45 am]
BILLING CODE 4910-13-U