[Federal Register Volume 64, Number 19 (Friday, January 29, 1999)]
[Rules and Regulations]
[Pages 4525-4526]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-2151]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98-ANE-14-AD; Amendment 39-11017; AD 99-03-03]
RIN 2120-AA64


Airworthiness Directives; Allison Engine Company Model AE 3007A 
and AE 3007A1/1 Turbofan Engines

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 Allison Engine Company Model AE 3007A turbofan 
engines, that currently requires reprogramming the Full Authority 
Digital Engine Control (FADEC) to software version VI.2. This amendment 
requires reprogramming the FADEC to a serviceable software version and 
reidentifying the FADEC assembly. This amendment is prompted by reports 
of at least seven uncommanded engine shutdowns, four of which occurred 
in flight, as a result of deficiencies in software version VI.2 on the 
AE 3007A engines and version VI.4 on the AE 3007A1/1 engines. The 
actions specified by this AD are intended to prevent an unintentional 
or uncommanded in-flight engine shutdown.

DATES: Effective February 16, 1999.
    Comments for inclusion in the Rules Docket must be received on or 
before March 30, 1999.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), New England Region, Office of the Regional 
Counsel, Attention: Rules Docket No. 98-ANE-14-AD, 12 New England 
Executive Park, Burlington, MA 01803-5299. Comments may also be sent 
via the Internet using the following address: ``9-ad-
[email protected].'' Comments sent via the Internet must contain the 
docket number in the subject line.

FOR FURTHER INFORMATION CONTACT: Kyri Zaroyiannis, Aerospace Engineer, 
Chicago Aircraft Certification Office, FAA, Small Airplane Directorate, 
2300 East Devon Avenue, Des Plaines, IL 60018; telephone (847) 294-
7836, fax (847) 294-7834.

SUPPLEMENTARY INFORMATION: On June 9, 1998, the Federal Aviation 
Administration (FAA) issued airworthiness directive (AD) 98-12-12, 
Amendment 39-10568 (63 FR 31338 June 9, 1998), to require programming 
the Full Authority Digital Engine Control (FADEC) with software version 
VI.2 (Allison Software part number 23068660; Allison FADEC assembly, 
with software VI.2 installed, part number 23068661). Additionally, the 
AD required that the FAA-approved Airplane Flight Manual be revised by 
incorporating the Embraer Flight Manual AFM 145/1153, Revision 14, 
dated May 7, 1998. These actions were prompted by reports of five in-
flight engine shutdowns on Allison Engine Company AE 3007 series 
turbofan engines due to inadequate fault accommodation logic. That 
condition, if not corrected, could result in an unintentional or 
uncommanded in-flight engine shutdown.
    Since the issuance of that AD, there have been at least seven 
uncommanded engine shutdowns, four of which occurred in flight, as a 
result of deficiencies in software version VI.2 on the AE 3007A engines 
and version VI.4 on the AE 3007A1/1 engines. Improved software version, 
VI.6A has been developed to address the deficiencies in software 
versions VI.2 and VI.4.
    The compliance hourly schedule of this AD was chosen based on 
overall fleet risk assessment of a hazardous condition occurring, parts 
availability, and shop capacity. The compliance end date was chosen to 
further assure the desired level of safety of this action as affected 
by aircraft utilization variations throughout the fleet.
    Since an unsafe condition has been identified that is likely to 
exist or develop on other Allison Engine Company AE 3007A and AE 
3007A1/1 turbofan engines of the same type design, this AD supersedes 
AD 98-12-12 to require replacing FADEC

[[Page 4526]]

assemblies, P/N 23062835, 23069253, 23068661, and 23068670 with 
serviceable parts.
    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 notice must submit a self-addressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket Number 98-ANE-14-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 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 removing Amendment 39-10568, (63 FR 
31338, June 9, 1998), and by adding a new airworthiness directive, 
Amendment 39-11017, to read as follows:

99-03-03  Allison Engine Company: Amendment 39-11017. Docket 98-ANE-
14-AD. Supersedes AD 98-12-12, Amendment 39-10568.

    Applicability: Allison Engine Company AE 3007A and AE 3007A1/1 
turbofan engines. These engines are installed on, but not limited to 
the following airplanes: Embraer Model EMB-145, EMB-145ER, EMB-
145MR, and EMB-145LR.

    Note 1: This airworthiness directive (AD) applies to each engine 
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 engines 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 (d) 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 an unintentional or uncommanded in-flight engine 
shutdown, accomplish the following:
    (a) Replace the Full Authority Digital Electronic Control 
(FADEC) assembly part numbers (P/N) 23062835, 23069253, 23068661, 
and 23068670, with serviceable parts within 200 flight hours after 
the effective date of this AD, but not later than April 30, 1999.
    (b) Prior to further flight, revise the FAA-approved Airplane 
Flight Manual by incorporating Embraer EMB-145 U.S. Airplane Flight 
Manual, Document No. AFM-145/1153, pages 3-14, 3-36B, 4-1, and 4-11, 
and 4-12 of Revision 14, dated May 7, 1998, until all affected 
engines within that operator's fleet are in compliance with this AD.
    (c) For the purpose of this AD, a serviceable part is any 
serviceable FADEC assembly except P/N's 23062835, 23069253, 
23068661, or 23068670. This AD action eliminates FADEC assembly P/
N's 23062835, 23069253, 23068661, or 2306867 from installation 
eligibility and continued use in service.

    Note 2: Complete instructions for reprogramming and 
reidentifying the existing FADEC are contained in Rolls-Royce SB AE 
3007A-73-021, Revision 1, dated December 23, 1998.

    (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, Chicago Aircraft Certification 
Office. Operators shall submit their requests through an appropriate 
FAA Principal Maintenance Inspector, who may add comments and then 
send it to the Manager, Chicago Aircraft Certification Office.

    Note 3: Information concerning the existence of approved 
alternative methods of compliance with this airworthiness directive, 
if any, may be obtained from the Chicago 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 aircraft to a location where 
the requirements of this AD can be accomplished.
    (f) This amendment becomes effective on February 16, 1999.

    Issued in Burlington, Massachusetts, on January 25, 1999.
David A. Downey,
Assistant Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.
[FR Doc. 99-2151 Filed 1-28-99; 8:45 am]
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