Airworthiness Directives; Allison Engine Company AE 3007A and 3007C Series Turbofan Engines

[Federal Register Volume 65, Number 174 (Thursday, September 7, 2000)]
[Rules and Regulations]
[Pages 54145-54147]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 00-22906]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2000-NE-33-AD; Amendment 39-11891; AD 2000-18-06]
RIN 2120-AA64


Airworthiness Directives; Allison Engine Company AE 3007A and 
3007C Series Turbofan Engines

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 Allison Engine Company AE 3007A and AE 3007C series 
turbofan engines with certain full authority digital electronic 
controls (FADEC's), listed by hardware serial number (SN), installed. 
This action requires inspections of installed FADEC's before further 
flight to be sure that no more than one engine with suspect FADEC's is 
installed on the same airplane, and eventual replacement of all of the 
suspect FADEC's with serviceable FADEC's. This amendment is prompted by 
reports of uncommanded in-flight shutdowns of engines. The actions 
specified in this AD are intended to prevent an uncommanded in-flight 
engine shutdown and the potential for an in-flight dual-engine shutdown 
caused by a potential hardware failure mode in some AE 3007 series 
FADEC's.

DATES: Effective September 22, 2000.
    Comments for inclusion in the Rules Docket must be received on or 
before November 6, 2000.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), New England Region, Office of the Regional 
Counsel, Attention: Rules Docket No. 2000-NE-33-AD, 12 New England 
Executive Park, Burlington, MA 01803-5299. Comments may also be sent 
via the Internet using the following address: ``[email protected]''. Comments sent via the Internet must contain the 
docket number in the subject line. The docket may be examined at the 
FAA, New England Region, Office of the Regional Counsel, 12 New England 
Executive Park, Burlington, MA.

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: The Allison Engine Company has notified the 
FAA that there is a quality problem with FADEC's that have certain 
hardware SN's installed on AE 3007 series engines. This can lead to an 
uncommanded engine shutdown in flight, the inability of the FADECs to 
switch from one channel to another channel (channel A to B), or the 
inability to shutdown an engine. Three uncommanded in-flight engine 
shutdowns, eight events in which the FADEC channels could not be 
changed, and three events in which the engine could not be shut down 
prompted these actions. Allison Engine Company has determined that 
these events resulted from a quality problem with the internal power 
supply transistor TR1 in FADEC's with certain hardware SN's. This 
condition, if not corrected, could also result in an uncommanded in-
flight engine shutdown and the potential for an in-flight dual-engine 
shutdown caused by a potential hardware failure mode in some AE 3007 
series FADEC's.
    The compliance times of this AD were chosen based on the risk 
analysis of a dual-engine shutdown. These compliance times assure the 
desired level of fleet safety of this action as a function of airplane 
utilization variations throughout the fleet.

Determination of an Unsafe Condition

    Since an unsafe condition has been identified that is likely to 
exist or develop on other engines of the same type design, this AD is 
being issued to require inspection of FADEC's for suspect hardware SN's 
and, if necessary, removal of that FADEC before further flight. This is 
to be sure that no more than one engine with FADEC's that have suspect 
hardware SN's is installed on each airplane. This AD will also require 
the replacement of all FADEC's that have suspect hardware SN's with 
serviceable FADEC's within 3 months after the effective date of this 
AD.

Immediate Adoption

    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 2000-NE-33-AD.'' The postcard will be date stamped and 
returned to the commenter.

Regulatory Impact

    This proposed rule does not have federalism implications, as 
defined in Executive Order No. 13132, because it would 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.

[[Page 54146]]

Accordingly, the FAA has not consulted with state authorities prior to 
publication of this proposed rule.

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 adding a new airworthiness 
directive, Amendment 39-11891, to read as follows:

2000-18-06  Allison Engine Company: Amendment 39-11891. Docket 2000-
NE-33-AD.

    Applicability: This AD is applicable to Allison Engine Company 
Models AE 3007A, AE 3007A1/1, AE 3007A1/2, AE 3007A1, AE 3007A1/3, 
AE 3007A1P, AE 3007A3, and AE 3007C turbofan engines with full 
authority digital electronic controls (FADEC's) that have the 
following hardware serial numbers (SN's) installed:

------------------------------------------------------------------------
              Engine model                      FADEC hardware SN
------------------------------------------------------------------------
AE 3007C...............................  BX55758, BX55760, BX55761,
                                          BX55763 through BX55765,
                                          BX55767, and BX61001 through
                                          BX61069, unless the FADEC has
                                          been repaired and marked as
                                          provided in paragraphs (f) and
                                          (g) of this AD.
 
AE 3007A, AE 3007A1/1, AE 3007A1/2,      BX56348, BX56361 through
 AE3007A1/3, AE 3007A1, AE 3007A1P, AE    BX56364, BX56374, BX56376,
 3007A3.                                  BX56392 through BX56395,
                                          BX59006, BX59007, BX59013,
                                          BX59014, BX59041, BX59050,
                                          BX59062, BX59064 through
                                          BX59066, BX59075 through
                                          BX59078, BX60000 through
                                          BX60145, BX60172 through
                                          BX60239, BX60265 through
                                          BX60287, BX60301, BX60303,
                                          BX60311, BX60381 through
                                          BX60384, unless the FADEC has
                                          been repaired and marked as
                                          provided in paragraphs (f) and
                                          (g) of this AD.
------------------------------------------------------------------------

    These engines are installed on, but not limited to Embraer Model 
EMB-145, EMB-145ER, EMB-145MR, EMB-145LR, EMB-135ER, EMB-135LR, and 
Cessna 750 airplanes.

    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 (h) 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: Compliance with this AD is required as indicated 
below, unless already done.
    To prevent an uncommanded in-flight engine shutdown and the 
potential for an in-flight dual-engine shutdown, do the following:

Inspection for FADEC Serial Number and Removal of FADEC's

    (a) Before further flight, inspect the FADEC for a SN that is 
listed in ``Applicability'' of this AD to be sure that no airplane 
has more than one engine with FADEC's that have suspect hardware 
SN's. The engine may have two FADEC's that have suspect hardware 
SN's.
    (b) If more than one engine per airplane is found with a FADEC 
that has a suspect hardware SN, remove the FADEC so there is only 
one engine per airplane with a FADEC that has a suspect hardware SN.
    (c) Removed suspect FADEC's may be returned to local stock.
    (d) The suspect FADEC's may be installed on another airplane as 
long as the requirements of paragraphs (a) and (e) of this AD are 
met.

Replacement of All Suspect FADEC's

    (e) Replace all FADEC's that have suspect hardware SN's with 
serviceable FADEC's within 3 months after the effective date of this 
AD.
    (f) After 3 months from the effective date of this AD, do not 
install a FADEC that has a hardware SN listed in ``Applicability'' 
of this AD on any engine unless the FADEC hardware has been repaired 
and the modification tag on the FADEC is marked with TR1 day/month. 
For example, a repair that was accomplished on September 25, 2000, 
will show as TR1 25/09.

Definition of a Serviceable FADEC

    (g) For the purpose of this AD, a serviceable FADEC is a FADEC 
that does not have a hardware SN listed in ``Applicability'' of this 
AD, unless the FADEC with the suspect hardware SN has been modified 
using Rolls-Royce (RR) service bulletin (SB) AE 3007A-73-042, 
Revision 1, dated August 23, 2000; or RR SB AE 3007C-73-024, 
Revision 1, dated August 23, 2000.

Alternative Methods of Compliance

    (h) An alternative method of compliance (AMOC) 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 2: Information concerning the existence of any approved 
AMOC with this airworthiness directive, may be obtained from the 
Chicago Aircraft Certification Office.

Special Flight Permit

    (i) Special flight permits may be issued in accordance with 
Secs. 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 
21.197 and 21.199) to operate the airplane to a location where the 
requirements of this AD can be accomplished.

Effective Date

    (j) This amendment becomes effective on September 22, 2000.


[[Page 54147]]


    Issued in Burlington, Massachusetts, on August 31, 2000.
David A. Downey,
Assistant Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.
[FR Doc. 00-22906 Filed 9-6-00; 8:45 am]
BILLING CODE 4910-13-P

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