[Federal Register: August 13, 2003 (Volume 68, Number 156)]
[Rules and Regulations]
[Page 48274-48275]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr13au03-3]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 2003-NM-142-AD; Amendment 39-13272; AD 2003-16-19]
RIN 2120-AA64
Airworthiness Directives; Learjet Model 45 Airplanes
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 all Learjet Model 45 airplanes. This action requires
replacement of the horizontal stabilizer actuator assembly (HSAA) with
a new HSAA. This action is necessary to prevent structural failure of
the HSAA, which could result in possible loss of control of the
airplane. This action is intended to address the identified unsafe
condition.
DATES: Effective August 13, 2003.
Comments for inclusion in the Rules Docket must be received on or
before October 14, 2003.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), Transport Airplane Directorate, ANM-114,
Attention: Rules Docket No. 2003-NM-142-AD, 1601 Lind Avenue, SW.,
Renton, Washington 98055-4056. Comments may be inspected at this
location between 9 a.m. and 3 p.m., Monday through Friday, except
Federal holidays. Comments may be submitted via fax to (425) 227-1232.
Comments may also be sent via the Internet using the following address:
9-anm-iarcomment@faa.gov. Comments sent via fax or the Internet must
contain ``Docket No. 2003-NM-142-AD'' in the subject line and need not
be submitted in triplicate. Comments sent via the Internet as attached
electronic files must be formatted in Microsoft Word 97 or 2000 or
ASCII text.
Information pertaining to this amendment may be examined at the
FAA, Transport Airplane Directorate, Rules Docket, 1601 Lind Avenue,
SW., Renton, Washington; or at the FAA, Wichita Aircraft Certification
Office, 1801 Airport Road, Room 100, Mid-Continent Airport, Wichita,
Kansas.
FOR FURTHER INFORMATION CONTACT: Greg Davied, Aerospace Engineer,
Airframe and Propulsion Branch, ACE-118W, FAA, Wichita Aircraft
Certification Office, 1801 Airport Road, Room 100, Mid-Continent
Airport, Wichita, Kansas 67209; telephone (316) 946-4128; fax (316)
946-4107.
SUPPLEMENTARY INFORMATION:
Background
On April 11, 2003, the FAA issued AD 2003-06-51, amendment 39-13121
(68 FR 19328, April 21, 2003), applicable to certain Learjet Model 45
airplanes, to require an inspection to determine the part number (P/N)
of the horizontal stabilizer actuator assembly (A66) (HSAA), and
replacement of any suspect HSAA (A66) having P/N 6627401000-001 or
SA9200F with a new or serviceable HSAA (A66) having P/N 6627401000-005.
That action was prompted by a report of severe vibration followed by a
rapid nose down pitch change on a Learjet Model 45 airplane. The cause
of the incident is attributed to brittle fracture material properties
of certain components of the HSAA. The requirements of that AD are
intended to prevent structural failure of the HSAA, which could result
in possible loss of control of the airplane.
FAA's Determination Since Issuance of AD 2003-06-51
Since issuance of AD 2003-06-51, we have determined that the MPC
Products Corporation acme screw having P/N 2A94568008 and nut having P/
N 2A94567005 within the new HSAA having P/N 6627401000-005 installed
per that AD are physically similar (not identical) to and have the same
material as the suspect assembly having P/N 6627401000-001. Although
the HSAA having P/N-005 is an improvement over the P/N-001, it was not
manufactured per the type design data. A brittle fracture could occur
on the acme screw and nut within the assembly having P/N-005, similar
to that on the assembly having P/N-001. During our investigation of
this problem, we determined that the configuration and quality controls
over the production of these parts were so deficient that we do not
have confidence that the airplane can be operated safely for any period
of time. Therefore, this AD allows operation only for the purpose of
positioning the airplane where the replacement required by this AD can
be accomplished. The airplane manufacturer is currently substantiating
the design data for the new replacement part. We anticipate that the
new part will be available in the near future.
Explanation of the Requirements of the Rule
Since an unsafe condition has been identified that is likely to
exist or develop on other airplanes of the same
[[Page 48275]]
type design registered in the United States, this AD requires
replacement of the HSAA with a new HSAA. The effect of this AD is that
operation is prohibited after the effective date of this AD, except to
position the airplane as described previously, until the required
replacement can be accomplished.
Interim Action
This is considered to be interim action until final action is
identified, at which time the FAA may consider further rulemaking.
Changes to 14 CFR Part 39/Effect on the AD
On July 10, 2002, we issued a new version of 14 CFR part 39 (67 FR
47997, July 22, 2002), which governs our AD system. The regulation now
includes material that relates to altered products, special flight
permits, and alternative methods of compliance (AMOCs). Because we have
now included this material in part 39, only the office authorized to
approve AMOCs is identified in each individual AD.
Determination of Rule's Effective Date
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 shall 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.
Submit comments using the following format:
[sbull] Organize comments issue-by-issue. For example, discuss a
request to change the compliance time and a request to change the
service bulletin reference as two separate issues.
[sbull] For each issue, state what specific change to the AD is
being requested.
[sbull] Include justification (e.g., reasons or data) for each
request.
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 2003-NM-142-AD.'' The postcard will be date stamped
and returned to the commenter.
Regulatory Impact
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, Safety.
Adoption of the Amendment
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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
0
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]
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2. Section 39.13 is amended by adding the following new airworthiness
directive:
2003-16-19 Learjet: Amendment 39-13272. Docket 2003-NM-142-AD.
Applicability: All Model 45 airplanes, certificated in any
category.
Compliance: Required as indicated, unless accomplished
previously.
To prevent structural failure of the horizontal stabilizer
actuator assembly (HSAA), which could result in possible loss of
control of the airplane, accomplish the following:
Replacement
(a) Except as provided by paragraph (b) of this AD, before
further flight after the effective date of this AD, replace the HSAA
having part number (P/N) 6627401000-005 with a new HSAA, per a
method approved by the Manager, Wichita Aircraft Certification
Office (ACO), FAA.
Flight Limits
(b) Non-revenue flights are permitted within 3 days after the
effective date of this AD only for the purpose of positioning the
airplane to a location where the replacement required by paragraph
(a) of this AD can be accomplished.
Parts Installation
(c) As of the effective date of this AD, no person may install
an HSAA, P/N 6627401000-005, on any airplane.
Alternative Methods of Compliance
(d) In accordance with 14 CFR 39.19, the Manager, Wichita
Aircraft Certification Office (ACO), FAA, is authorized to approve
alternative methods of compliance for this AD.
Effective Date
(e) This amendment becomes effective August 13, 2003.
Issued in Renton, Washington, on August 8, 2003.
Vi L. Lipski,
Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 03-20699 Filed 8-12-03; 8:45 am]
BILLING CODE 4910-13-P