[Federal Register Volume 62, Number 122 (Wednesday, June 25, 1997)]
[Rules and Regulations]
[Pages 34163-34165]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-16568]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 96-SW-35-AD; Amendment 39-10056; AD 97-13-09]
RIN 2120-AA64
Airworthiness Directives; McDonnell Douglas Helicopter Systems
Model MD-900 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 McDonnell Douglas Helicopter Systems (MDHS) Model MD-
900 helicopters. This action requires applying specified serial numbers
to the left and right vertical stabilizer control system (VSCS)
bellcrank assemblies, the forward and aft deck-fitting assemblies, and
the mid-forward and mid-aft truss strut assemblies; and establishes new
life limits for the non-rotating swashplate assembly, the collective
drive link assembly, and the self-aligning, spherical/slider main rotor
bearing. This amendment is prompted by additional manufacturer's
analysis which indicates a need for the reduction of the life limit on
several parts and the addition of non-serialized parts to the life-
limited parts list. The actions specified in this AD are intended to
establish a life limit for various parts and reduce the current life
limit on other parts.
DATES: Effective July 10, 1997.
The incorporation by reference of certain publications listed in
the regulations is approved by the Director of the Federal Register as
of July 10, 1997.
Comments for inclusion in the rules docket must be received on or
before August 25, 1997.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), Office of the Assistant Chief Counsel, Attention:
Rules Docket No. 96-SW-35-AD, 2601 Meacham Blvd., Room 663, Fort Worth,
Texas 76137.
[[Page 34164]]
The service information referenced in this AD may be obtained from
McDonnell Douglas Helicopter Systems, Technical Publications, Bldg.
530/B11, 5000 E. McDowell Road, Mesa, Arizona 85205-9797. This
information may be examined at the FAA, Office of the Assistant Chief
Counsel, 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: Mr. Greg DiLibero, Aerospace Engineer,
Airframe Branch, Los Angeles Aircraft Certification Office, FAA, 3960
Paramount Boulevard, Lakewood, California 90712, telephone (562) 627-
5231, fax (562) 627-5210.
SUPPLEMENTARY INFORMATION: This amendment adopts a new AD that is
applicable to MDHS Model MD-900 helicopters. For Model MD-900
helicopters with serial numbers (S/N) 0002 through 0012, this action
requires applying serial numbers to the mid-forward truss assembly,
part number (P/N) 900F2401200-102, and the forward and aft deck-fitting
assemblies, P/N 900F2401500-103 and P/N 900F2401600-103. For Model MD-
900 helicopters with S/N 0002 through 0048, this action requires
applying S/N's to the VSCS bellcrank assemblies, part number (P/N)
900F2341712-101 or P/N 900FP341712-103, and the mid-aft truss strut
assembly, P/N 900F2401300-103. For all Model MD-900 helicopters, this
action reduces the life limits for the non-rotating swashplate
assembly, P/N 900C2010192-105, -107, -109, or -111, from 8,300 hours
time-in-service (TIS) to 554 hours TIS; the collective drive link
assembly, P/N 900C2010207-101, from 3,900 hours TIS to 1,480 hours TIS;
the self-aligning, spherical/slider main rotor bearing, P/N
900C3010042-103, from 2,100 hours TIS to 480 hours TIS; and the VSCS
bellcrank assembly, P/N 900FP341712-103, and bellcrank arm, P/N
900F2341713-101, (used in the VSCS bellcrank assembly, P/N 900F2341712-
101) from no life limit to 2,700 hours TIS. This amendment is prompted
by additional manufacturer's analysis which indicates a need for the
reduction of the life limit on several parts and the addition of non-
serialized parts to the life-limited parts list. The actions specified
in this AD are intended to establish a life limit for various parts and
reduce the current life limit on other parts.
The FAA has reviewed McDonnell Douglas Helicopter Systems Service
Bulletin No. SB900-039, Revision 2, dated March 12, 1997, which
describes procedures for applying the serial numbers to the life-
limited parts.
Since an unsafe condition has been identified that is likely to
exist or develop on other MDHS Model MD-900 helicopters of the same
type design, this AD is being issued to establish a life limit for
various parts and reduce the current life limit on other parts. This AD
requires applying specified serial numbers to the left and right VSCS
bellcrank assemblies, P/N 900F2341712-101 or P/N 900FP341712-103; to
the mid-forward and mid-aft truss strut assemblies, P/N 900F2401200-102
and P/N 900F2401300-103; and to the forward and aft deck-fitting
assemblies, P/N 900F2401500-103 and P/N 900F2401600-103. This AD also
reduces the life limits for the non-rotating swashplate assembly, P/N
900C2010192-105, -107, -109, or -111, from 8,300 hours TIS to 554 hours
TIS; the collective drive link assembly, P/N 900C2010207-101, from
3,900 hours TIS to 1,480 hours TIS; the self-aligning, spherical/slider
main rotor bearing, P/N 900C3010042-103, from 2,100 hours TIS to 480
hours TIS; and the VSCS bellcrank assembly, P/N 900FP341712-103, and
the bellcrank arm, P/N 900F2341713-101, (used in the VSCS bellcrank
assembly, P/N 900F2341712-101) from no life limit to 2,700 hours TIS.
The serial numbers for the VSCS bellcrank assemblies, the mid-forward
and mid-aft truss assemblies, and the forward and aft deck-fitting
assemblies are specified in and are required to be accomplished in
accordance with the service bulletin described previously. The serial
numbers specified in the service bulletin shall be applied adjacent to
the existing P/N's. Some Model MD-900 helicopters that are currently in
service are equipped with helicopter control system parts that are
approaching the new, lower life limits. Failure of any of these parts
could result in loss of control of the helicopter. Due to the
criticality of the components of the helicopter control system, this AD
is being issued in the form of an immediately-adopted final rule with
request for comments.
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 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. 96-SW-35-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
[[Page 34165]]
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:
AD 97-13-09 McDonnell Douglas Helicopter Systems: Amendment 39-
10056. Docket No. 96-SW-35-AD.
Applicability: Model MD-900 helicopters, 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 establish a life limit for various parts and reduce the
current life limit on other parts, accomplish the following:
(a) Within 100 hours time-in-service (TIS) after the effective
date of this AD:
(1) For Model MD-900 helicopters with serial number (S/N) 0002
through 0012, apply serial numbers to the mid-forward truss
assembly, P/N 900F2401200-102, and the forward and aft deck-fitting
assemblies, P/N 900F2401500-103 and P/N 900F2401600-103.
(2) For Model MD-900 helicopters with S/N 0002 through 0048,
apply S/N's to the left and right vertical stabilizer control system
(VSCS) bellcrank assemblies, P/N 900F2341712-101 or P/N 900FP341712-
103, and the mid-aft truss strut assembly, P/N 900F2401300-103.
(3) Apply the S/N's as specified in paragraphs (a)(1) and (a)(2)
of this AD adjacent to the existing P/N's, and in accordance with
the Accomplishment Instructions of McDonnell Douglas Helicopter
Systems Service Bulletin No. SB900-039, Revision 2, dated March 12,
1997.
(b) Before further flight, remove from service:
(1) The non-rotating swashplate assembly, P/N 900C2010192-105, -
107, -109, or -111, on or before attaining 554 hours TIS.
(2) The collective drive link assembly, P/N 900C2010207-101, on
or before attaining 1,480 hours TIS.
(3) The self-aligning, spherical/slider main rotor bearing, P/N
900C3010042-103, on or before attaining 480 hours TIS.
(4) The VSCS bellcrank assembly, P/N 900FP341712-103, and
bellcrank arm, P/N 900F2341713-101 (used in the VSCS bellcrank
assembly, P/N 900F2341712-101), on or before attaining 2,700 hours
TIS.
(c) This AD revises the Airworthiness Limitations section of the
maintenance manual by establishing new retirement lives for these
parts.
(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. 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 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.
(f) The modification shall be done in accordance with McDonnell
Douglas Helicopter Systems Bulletin No. SB900-039, Revision 2, dated
March 12, 1997. 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 McDonnell Douglas
Helicopter Systems, Technical Publications, Bldg. 530/B11, 5000 E.
McDowell Road, Mesa, Arizona 85205-9797. Copies may be inspected at
the FAA, Office of the Assistant Chief Counsel, 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 July 10, 1997.
Issued in Fort Worth, Texas, on June 17, 1997.
Eric Bries,
Acting Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. 97-16568 Filed 6-24-97; 8:45 am]
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