Nachrichten für Luftfahrer 2006 Teil II (weicht ggf. von Druckversion ab)
Aircraft Models
AIRWORTHINESS DIRECTIVE U.S. Department
of Transportation B–N Group Ltd. BN–2T and BN–2T–4R.
www.faa.gov/aircraft/safety/alerts/ Federal Aviation SIAI Marchetti s.r.l. SF600, SF600A.
Administration
www.gpoaccess.gov/fr/advanced.html
Unsafe Condition
2006-13-06 Rolls-Royce Corporation (formerly Allison Engine Company, Allison Gas Turbine
Division, and Detroit Diesel Allison): Amendment 39-14659. Docket No. FAA-2005-22594; (d) This AD results from eleven reports of RRC tie bolt failure due to high-cycle-fatigue. We are
Directorate Identifier 2005-NE-28-AD. issuing this AD to prevent tie bolt failure that could cause loss of engine power, resulting in a first
stage turbine wheel overspeed and an uncontained engine failure.
Effective Date
Compliance
(a) This airworthiness directive (AD) becomes effective July 26, 2006.
(e) You are responsible for having the actions required by this AD performed within the
Affected ADs compliance times specified unless the actions have already been done.
(b) None. Remove Gas Producer Rotor Assembly Tie Bolts
Applicability (f) Remove the P/N gas producer rotor assembly tie bolts listed in Table 1 of this AD from
service the next time they are disassembled for any reason, or by October 31, 2011, whichever occurs
(c) This AD applies to Rolls-Royce Corporation (formerly Allison Engine Company, Allison first, and replace with tie bolts with P/Ns that are not listed in Table 1 of this AD.
Gas Turbine Division, and Detroit Diesel Allison) 250-B17, -B17B, -B17C, -B17D, -B17E, -B17F, -
B17F/1, -B17F/2, 250-C18, -C20, -C20B, -C20F, -C20J, -C20R, -C20R/1, -C20R/2, -C20R/4, -C20S, (g) After the effective date of this AD, do not install any gas producer rotor assembly tie bolt
and ''C20W series turboprop and turboshaft engines with the gas producer rotor assembly tie bolt part P/Ns listed in Table 1 of this AD in any RRC 250-B and 250-C Series turboprop and turboshaft
numbers (P/Ns) listed in the following Table 1, installed: engines.
TABLE 1.—AFFECTED GAS PRODUCER ROTOR ASSEMBLY TIE BOLTS Alternative Methods of Compliance
Manufacturer Affected part numbers
EXTEX Ltd. (EXTEX) A23008020 and E23008020 (h) The Manager, Los Angeles Aircraft Certification Office, has the authority to approve
Rolls-Royce Corporation (RRC) 23008020, 6843388 and 6876991 alternative methods of compliance for EXTEX, and Pacific Sky Supply Inc. gas producer rotor
Superior Air Parts Inc. (SAP) A23008020 assembly tie bolts addressed in this AD, if requested, using the procedures found in 14 CFR 39.19.
The Manager, Chicago Aircraft Certification Office, has the authority to approve alternative methods
Pacific Sky Supply Inc 23008020P
of compliance for RRC gas producer rotor assembly tie bolts addressed in this AD, if requested,
using the procedures found in 14 CFR 39.19. The Manager, Southwest Special Certification Office,
These engines are installed on, but not limited to, aircraft in the following Table 2:
has the authority to approve alternative methods of compliance for SAP gas producer rotor assembly
tie bolts addressed in this AD, if requested, using the procedures found in 14 CFR 39.19.
TABLE 2.—APPLICABLE AIRCRAFT
Helicopter Models Related Information
Agusta A109, A109A, A109A II, A109C.
Arrow Falcon Exporters OH–58A+ and OH–58C. (i) RRC Commercial Engine Bulletin (CEB) CEB A-304, CEB A-1371, CEB A-72-4076, TP
Bell Textron 206A, 206B, 206L. CEB A-176, TP CEB A-1319, TP CEB A-72-2027, Revision N/C, dated May 23, 2005, and EXTEX
Enstrom TH–28, 480, 480B. Service Bulletin T-090, Revision N/C, dated May 23, 2005, pertain to the subject of this AD.
Eurocopter France AS355E, AS355F, AS355F1, AS355F2.
Eurocopter Deutschland BO–105A, BO–105C, BO–105S. Issued in Burlington, Massachusetts, on June 14, 2006.
FH–1100 Manufacturing Corp. FH–1100. Francis A. Favara,
Garlick OH–58A + OH–58C. Manager, Engine and Propeller Directorate, Aircraft Certification Service.
McDonnell Douglas Company 369D, 369E, 369F, 369H, 369HM, 369HS, 369HE, 500N. [FR Doc. 06-5547 Filed 6-20-06; 8:45 am]
San Joaquin OH–58A+ and OH–58C. BILLING CODE 4910-13-P
Schweizer 269D.
5 6
Sicherheit des Luftverkehrs, das in diesem Fall das Interesse des Adressaten am Aufschub der angeordneten Maßnahmen überwiegt, ist es
Lufttüchtigkeitsanweisung erforderlich, die sofortige Vollziehung dieser LTA anzuordnen.
LTA-Nr.: D-2006-234 Rechtsbehelfsbelehrung:
Gegen diese Verfügung kann innerhalb eines Monats nach Bekanntgabe Widerspruch eingelegt werden. Der Widerspruch ist schriftlich oder
zur Niederschrift beim Luftfahrt-Bundesamt, Hermann-Blenk-Str. 26, 38108 Braunschweig einzulegen.
Luftfahrt-Bundesamt
Datum der Bekanntgabe: 18.08.2006 LTAs werden auch im Internet unter http://www.lba.de publiziert
***
Muster: Honeywell International AD der ausländischen Behörde:
TPE331 FAA AD 2006-14-03 Amdt. 39-14674
TSE331
Geräte-Nr.: Technische Mitteilungen des Herstellers:
7015, 7021 AlliedSignal SB TPE331-72-0117 Rev. 11 vom 13.11.1997
Honeywell ASB TPE331-A72-2111 vom 12.11.2002
Honeywell ASB TPE331-A72-2123 vom 08.02.2006
Honeywell ASB TPE331-A72-2130 vom 27.09.2005
Honeywell ASB TPE331-A72-2131 vom 27.09.2005
Honeywell SB TPE/TSE331-72-0019 Rev. 22 vom 16.05.2001
Honeywell SB TPE331-72-0180 Rev. 31 vom 07.11.2003
Honeywell SB TPE331-72-0476 Rev. 27 vom 17.09.2003
Betroffenes Luftfahrtgerät:
Honeywell International
TPE331, TSE331
- Baureihen: TPE331-1, -1U, -1UA
TPE331-2, -2UA
TPE331-3U, -3UW, -3W
TPE331-5, -5A, -5AB, -5B, -5U
TPE331-6, -6A, -6U
TPE331-8, -8A
TPE331-9, -9U
TPE331-10, -10A, -10AV, -10B, -10G, -10GP, -10GR, -10GT, -10J, -10N
TPE331-10P, -10R, -10T, -10U, -10UA, -10UF, -10UG, -10UGR, -10UJ, -10UK, -10UR
TPE331-11U, -11UA
TPE331-12, -12B, -12JR, -12UA, -12UAR, -12UER, -12UHR
TSE331-3U
- Werk-Nrn.: Alle
Betrifft:
Festlegung neuer zulässiger Betriebszeiten für Turbinenscheiben der 1. bis 3. Turbinenstufe in Triebwerken,
die unter besonderen operationellen Bedingungen betrieben werden.
Maßnahmen:
Detaillierte Informationen über die durchzuführenden Maßnahmen sind der oben genannten FAA
Airworthiness Directive und den genannten technischen Mitteilungen des Herstellers zu entnehmen.
Alle erforderlichen Maßnahmen zur Abstellung des technischen Mangels müssen ordnungsgemäß,
vollständig und innerhalb der vorgesehen Fristen auf Basis der genannten Bezugsdokumente durchge-
führt werden. Alle Abweichungen von den Maßnahmen und Fristen dieser Lufttüchtigkeitsanweisung
bedürfen der vorherigen Zustimmung durch das Luftfahrt-Bundesamt.
Fristen:
Alle anzuwendenden Fristen sind der oben genannten FAA Airworthiness Directive zu entnehmen.
Die Laufzeit aller anzuwendenden Fristen beginnt mit dem Datum der Inkraftsetzung der genannten
FAA Airworthiness Directive.
Diese Lufttüchtigkeitsanweisung entspricht hinsichtlich der durchzuführenden Maßnahmen und Fristen der
FAA AD 2006-14-03 Amdt. 39-14674
Durch die vorgenannten Mängel ist die Lufttüchtigkeit des Luftfahrtgerätes derart beeinträchtigt, daß es nach Ablauf der genannten Fristen
nur in Betrieb genommen werden darf, wenn die angeordneten Maßnahmen ordnungsgemäß durchgeführt worden sind. Im Interesse der
Aktenzeichen: (10)T23-502.1/D-2006-234 Seite 1 von 2 Aktenzeichen: (10)T23-502.1/D-2006-234 Seite 2 von 2
[Federal Register: July 5, 2006 (Volume 71, Number 128)] SUPPLEMENTARY INFORMATION: The FAA proposed to amend 14 CFR part 39 with a
[Rules and Regulations] proposed AD. The proposed AD applies to certain Honeywell International Inc. TPE331 series
[Page 38054-38059] turboprop, and TSE331-3U model turboshaft engines. We published the proposed AD in the Federal
From the Federal Register Online via GPO Access [wais.access.gpo.gov] Register on February 23, 2006 (71 FR 9281). That action proposed to require implementing a new
[DOCID:fr05jy06-3] flight cycle counting method for first, second, and third-stage turbine rotors used in aircraft that make
––––––––––––––––––––––––––––––––––– multiple takeoffs and landings without an engine shutdown, and removing turbine rotors from service
that have reached or exceeded their cycle life limits. This new flight cycle counting method requires
DEPARTMENT OF TRANSPORTATION determining total equivalent cycles accrued.
Federal Aviation Administration Examining the AD Docket
14 CFR Part 39 You may examine the docket that contains the AD, any comments received, and any final
disposition in person at the Docket Management Facility Docket Office between 9 a.m. and 5 p.m.,
[Docket No. FAA-2006-23704; Directorate Identifier 2006-NE-02-AD; Amendment 39-14674; Monday through Friday, except Federal holidays. The Docket Office (telephone (800) 647-5227) is
AD 2006-14-03] located on the plaza level of the Department of Transportation Nassif Building at the street address
stated in ADDRESSES. Comments will be available in the AD docket shortly after the DMS receives
RIN 2120-AA64 them.
Airworthiness Directives; Honeywell International Inc. TPE331 Series Turboprop, and Comments
TSE331-3U Model Turboshaft Engines
We provided the public the opportunity to participate in the development of this AD. We have
AGENCY: Federal Aviation Administration (FAA), Department of Transportation (DOT). considered the comments received.
ACTION: Final rule. Suggestion To Delete Phrase ''To Ground Idle''
––––––––––––––––––––––––––––––––––– One commenter suggests that in the Discussion paragraph of the proposed AD, we delete the
phrase ''to ground idle''. Doing this would reconcile the Discussion paragraph with the Definition
SUMMARY: The FAA is adopting a new airworthiness directive (AD) for certain Honeywell paragraph (i) in the compliance section, because touch-and-go maneuvers require the logging of
International Inc. TPE331 series turboprop, and TSE331-3U model turboshaft engines. This AD partial cycles. A touch-and-go maneuver is a landing and takeoff without shutdown.
requires implementing a new flight cycle counting method for first, second, and third-stage turbine We partially agree. The damage fraction for a minor cycle identified in the Honeywell Alert
rotors used in aircraft that make multiple takeoffs and landings without an engine shutdown, and Service Bulletins is based on landings to normal ground-idle engine speed reductions without an
removing turbine rotors from service that have reached or exceeded their cycle life limits. This new engine shutdown. Any engine operation, such as a touch-and-go maneuver with an engine speed
flight cycle counting method requires determining total equivalent cycles accrued. This AD results reduction to ground idle during touch-down, counts as a minor cycle. Engine speed reductions to
from several reports of uncontained turbine rotor separation on engines used in special-use ground idle during landing are an important factor in determining the counting of a minor cycle and,
operations. We are issuing this AD to prevent uncontained failure of the turbine rotor due to low- therefore, must be included in the definition. The AD does not repeat the proposed AD Discussion
cycle-fatigue (LCF), and damage to the aircraft. paragraph. We agree that the wording in our NPRM could be clearer. Therefore, we changed
Definition paragraph (i), to include major and minor cycles, and paragraph (o), to state that a minor
DATES: This AD becomes effective August 9, 2006. The Director of the Federal Register approved cycle, which occurs within a major cycle, is an additional landing with an engine speed reduction to
the incorporation by reference of certain publications listed in the regulations as of August 9, 2006. ground idle with no engine shutdown, followed by a takeoff.
ADDRESSES: You can get the service information identified in this AD from Honeywell Engines, Request To Change Compliance Section Paragraph (f)(1)(ii)
Systems & Services, Technical Data Distribution, M/S 2101-201, P.O. Box 52170, Phoenix, AZ
85072-2170; telephone: (602) 365-2493 (General Aviation); (602) 365-5535 (Commercial); fax: One commenter requests that we change compliance section paragraph (f)(1)(ii) from ''If you are
(602) 365-5577 (General Aviation and Commercial). unable to determine equivalent cycles for prior special-use operations, you must use a onetime
You may examine the AD docket on the Internet at http://dms.dot.gov or in Room PL-401 on the takeoff-to-engine shutdown ratio of six to estimate prior special-use equivalent cycles for each
plaza level of the Nassif Building, 400 Seventh Street, SW., Washington, DC. turbine rotor'' to ''For turbine rotors known to have prior special use operation, if you are unable to
determine equivalent cycles for prior special-use operations, you must use a onetime takeoff-to-
FOR FURTHER INFORMATION CONTACT: Joseph Costa, Aerospace Engineer, Los Angeles engine shutdown ratio of six to estimate prior special-use equivalent cycles for each turbine rotor.''
Aircraft Certification Office, FAA, Transport Airplane Directorate, 3960 Paramount Blvd., The commenter feels that this would clarify the phrase ''unable to determine'' because as-written it
Lakewood, CA 90712-4137; telephone (562) 627-5246; fax (562) 627-5210. could be construed to mean that a rotor had special use operation, but exact minor-to-major cycle
count cannot be determined.
1 2
We partially agree. We agree with the commenter's application of the phrase ''unable to Suggestion That AD Action Does Not Target the Problem
determine'' but we do not agree that paragraph (f)(1)(ii) should be changed. That paragraph must be
read in context with paragraph (f), which clearly states ''For turbine rotors installed before the Two commenters suggest that the AD action does not target the problem of why most turbine
effective date of this AD, and currently or previously used in special-use operations:'' However, we rotors fail. The commenters state that the proposed AD should be withdrawn.
did clarify paragraph (f)(1)(ii) to add the reason why the operator or owner would be unable to We do not agree. The AD addresses our safety concern that use of the TPE331 engine beyond its
determine equivalent cycles. original certified intended assumption of one cycle for each flight threatens safe operations. We
understand that the AD does not address all causes for turbine rotor failure. We are investigating
Request To Change the Phrase ''Used Turbine Rotors'' in Compliance Paragraph (f) other turbine rotor features that may cause failures, and we may consider future AD action. We did
not change the AD.
One commenter requests that we change the phrase ''used turbine rotors'' in compliance
paragraph (f) to ''turbine rotors'' as these rotors may have had zero cycles-since-new at installation. Ten Percent Estimate Seems Low
We agree. The compliance action is the same for new or used turbine rotors installed before the
effective date of the AD. We made that change in the AD. One commenter states that the proposed AD estimate of ten percent of affected engines are used
on MU-2B airplanes, seems low, and that the special-use industry such as skydiving, agriculture, and
Request To Add a Step to Compliance Paragraphs (f) and (g) some cargo, is a large industry.
We do not agree. Ten percent of the affected engines being used on MU-2B airplanes, is our best
One commenter requests that we add a step to compliance paragraphs (f) and (g) to include the estimate based on FAA experience with special-use operators and the MU-2 fleet size.
new counting method, which is also referenced in paragraph (h)(1) of the compliance section. The
commenter states that this counting method should be used after determining equivalent cycles, Root of the Problem Seems To Be in Manufacturing
whether the turbine rotor is new or used.
We partially agree. We agree that operators and maintenance personnel use the new counting One commenter states that the root of the problem seems to be in manufacturing. The commenter
method of counting major and minor cycles when accrued for new and used turbine rotors after the asks if Honeywell International Inc. will provide a turbine rotor that can withstand low-cycle-fatigue.
initial assessment from the Table 1 turbine removal schedules in the Honeywell ASBs. This schedule We do not agree. We investigated the production and manufacturing of the affected turbine
requires retiring the turbine rotors within a specified number of equivalent cycles, which infers that rotors and found no anomalies. Therefore, we concluded that the existing turbine rotors were
the owner or operator use the new counting method with minor and major cycles. We changed manufactured to type design. However, we may consider future AD action if we find such action
compliance section paragraph (f)(1)(ii) to read ''If you are unable to determine equivalent cycles for necessary.
prior special-use operations due to the absence of actual data regarding the number of takeoffs and
landings per major cycle, you must use a onetime ratio of six takeoffs and landings per major cycle to Conclusion
estimate prior special-use equivalent cycles for each turbine rotor''. Also, for clarification, we
changed compliance section paragraph (h)(1) to read ''Use the new counting method by counting and We have carefully reviewed the available data, including the comments received, and determined
recording minor and major cycles when accrued, and determine equivalent cycles by the method that air safety and the public interest require adopting the AD with the changes described previously.
described in paragraph (f)(1)(i) and (f)(1)(iii) of this AD''. We have determined that these changes will neither increase the economic burden on any operator
In preparing the response to this commenter, we decided that proposed paragraphs (h) and (h)(2) nor increase the scope of the AD.
could be clearer. Therefore, we changed compliance section paragraph (h) to read ''For all new (zero
cycles) turbine rotors installed on or after the effective date of this AD used in special-use Costs of Compliance
operations:'' and paragraph (h)(2) to read ''Using the ratio of six takeoffs and landings per major cycle
for unknown cycle history, as referenced in paragraph (f)(1)(ii) of this AD, is not permitted''. We estimate that this AD will affect 200 TPE331 series turboprop, and TSE331-3U model
turboshaft engines installed on airplanes and helicopters of U.S. registry. We also estimate that it will
Comment That Previous Method of Counting Cycles Is Acceptable take about two work-hours per engine to perform the total equivalent cycles determination and
recording. We also estimate that to replace a turbine rotor will take 40 work-hours per engine when
One commenter states that the previous method of counting cycles is acceptable and that major done at an unscheduled maintenance interval. We also estimate that 38 rotors will be replaced at
and minor counting is unnecessary. The commenter cites their ''lower than red-line'' engine operation unscheduled maintenance intervals. We estimate the average labor rate to be $65 per work-hour.
temperatures are an additional safety margin (excluding temperatures during startups and shutdowns). Required parts will cost about $20,000 per engine. The costs associated with this AD are dependent
We do not agree. The new counting method is necessary to preclude fatigue damage of turbine on the engine mission cycle. Operators accruing many minor and major cycles might replace first and
rotors and is appropriate for most operations when considering engine operation temperatures and second stage turbine rotors every two years. For the purpose of this AD, we estimate the costs for an
rotor speeds. We did not change the AD based on this comment. eight-year period with moderate usage to be 10 minor cycles each flight and 200 flights each year,
and the effective use of the first and second turbine rotors to be equivalent to 2,600 cycles. Based on
these figures, we estimate the total cost to U.S. operators to be $9,350,630.
The Agency is committed to updating the aviation community of expected costs associated with
the MU-2B series airplane safety evaluation conducted in 2005. As a result of that commitment, the
accumulating expected costs of all ADs related to the MU-2B series airplane safety evaluation may
3 4
be found at the following Web site: http://www.faa.gov/aircraft/air_cert/design_approvals/small_
airplanes/cos/mu2_foia_reading_library/ AIRWORTHINESS DIRECTIVE U.S. Department
of Transportation
www.faa.gov/aircraft/safety/alerts/ Federal Aviation
Authority for This Rulemaking Administration
www.gpoaccess.gov/fr/advanced.html
Title 49 of the United States Code specifies the FAA's authority to issue rules on aviation safety.
2006-14-03 Honeywell International Inc. (formerly AlliedSignal Inc., Garrett Engine Division;
Subtitle I, Section 106, describes the authority of the FAA Administrator. Subtitle VII, Aviation
Garrett Turbine Engine Company; and AiResearch Manufacturing Company of Arizona):
Programs, describes in more detail the scope of the Agency's authority.
Amendment 39-14674. Docket No. FAA-2006-23704; Directorate Identifier 2006-NE-02-AD.
We are issuing this rulemaking under the authority described in Subtitle VII, Part A, Subpart III,
Section 44701, ''General requirements.''Under that section, Congress charges the FAA with
Effective Date
promoting safe flight of civil aircraft in air commerce by prescribing regulations for practices,
methods, and procedures the Administrator finds necessary for safety in air commerce. This
(a) This airworthiness directive (AD) becomes effective August 9, 2006.
regulation is within the scope of that authority because it addresses an unsafe condition that is likely
to exist or develop on products identified in this rulemaking action.
Affected ADs
Regulatory Findings
(b) None.
We have determined that this AD will not have federalism implications under Executive Order
Applicability
13132. This AD 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
(c) This AD applies to Honeywell International Inc. TPE331-1, -1U, -1UA, -2, -2UA, -3U, -
various levels of government.
3UW, -3W, -5, -5A, -5AB, -5B, -5U, -6, -6A, -6U, -8, -8A, -9, -9U, -10, -10A, -10AV, -10B, -10G, -
For the reasons discussed above, I certify that this AD:
10GP, -10GR, -10GT, -10J, -10N, -10P, -10R, -10T, -10U, -10UA, -10UF, -10UG, -10UGR, -10UJ, -
(1) Is not a ''significant regulatory action'' under Executive Order 12866;
10UK, -10UR, -11U, -11UA, -12, -12B, -12JR, -12UA, -12UAR, -12UER, and -12UHR series
(2) Is not a ''significant rule'' under DOT Regulatory Policies and Procedures (44 FR 11034,
turboprop and TSE331-3U model turboshaft engines. These engines are installed on, but not limited
February 26, 1979); and
to, the following aircraft:
(3) Will not have a significant economic impact, positive or negative, on a substantial number of
small entities under the criteria of the Regulatory Flexibility Act.
We prepared a summary of the costs to comply with this AD and placed it in the AD Docket. Manufacturer Airplane model
You may get a copy of this summary at the address listed under ADDRESSES. Aero Planes, LLC (formerly McKinnon Enterprises) G–21G.
Allied AG Cat Productions (formerly Schweizer) G–164 series.
List of Subjects in 14 CFR Part 39 Ayres S–2R series.
British Aerospace Ltd (formerly Jetstream) 3201 series, and HP.137 Jetstream MK.1.
Air transportation, Aircraft, Aviation safety, Incorporation by reference, Safety. Cessna Aircraft Company 441 Conquest.
Construcciones Aeronauticas, s.a. (CASA) C–212 series.
Adoption of the Amendment DeHavilland DH104 series 7AXC (Dove).
Dornier 228 series.
Accordingly, under the authority delegated to me by the Administrator, the Federal Aviation Fairchild SA226 AND SA227 series (Swearingen
Administration amends 14 CFR part 39 as follows: Merlin and Metro series).
Grumman American G–164 series.
PART 39–AIRWORTHINESS DIRECTIVES Mitsubishi MU–2B series (MU–2 series).
Pilatus PC–6 series (Fairchild Porter and
1. The authority citation for part 39 continues to read as follows: Peacemaker).
Polskie Zaklady Lotnicze Spolka (formerly Wytwornia PZL M18, PZL M18A, PZL M18B.
Authority: 49 U.S.C. 106(g), 40113, 44701. Sprzetu Komunikacyjnego).
Prop-Jets, Inc. 400.
§ 39.13 [Amended] Raytheon Aircraft (formerly Beech) C45G, TC–45G, C–45H, TC–45H, TC–45J,
G18S, E18S–9700, D18S, D18C, H18, RC–
2. The FAA amends § 39.13 by adding the following new airworthiness directive: 45J, JRB–6, UC–45J, 3N, 3NM, 3TM, B100,
C90, and E90.
5 6
Manufacturer Airplane model TABLE B.—SERVICE BULLETINS (SBS) FOR RECORDING TOTAL EQUIVALENT
Shorts Brothers and Harland, Ltd. SC7 (Skyvan) series. CYCLES
Thrush (Rockwell Commander) S–2R. For engines Record using
Twin Commander (Jetprop Commander) 680 and 690 series. (A) TPE331–1 through –6 series and Honeywell SB No. TPE/TSE331–72–0019, Revision 22,
Manufacturer Helicopter Model TSE331–3U model dated May 16, 2001.
Sikorsky S–55 series (Helitec Corp. S55T). (B) TPE331–8 through –9 series AlliedSignal SB No. TPE331–72–0117, Revision 11, dated
November 13, 1997.
Unsafe Condition (C) TPE331–10 through –11 series Honeywell SB No. TPE331–72–0180, Revision 31, dated
November 7, 2003.
(d) This AD results from several reports of uncontained turbine rotor separation on engines used (D) TPE331–12 series Honeywell SB No. TPE331–72–0476, Revision 27, dated
in special-use operations. We are issuing this AD to prevent uncontained failure of the turbine rotor September 17, 2003.
due to low-cycle-fatigue (LCF), and damage to the aircraft.
(2) Remove from service turbine rotors affected by paragraph (f)
Compliance of this AD using the applicable Turbine Rotor Removal Schedule in Table A of this AD, or, within
nine months after the effective date of this AD, whichever occurs later.
(e) You are responsible for having the actions required by this AD performed within the
compliance times specified unless the actions have already been done. Used Turbine Rotors Installed On or After the Effective Date of this AD
Turbine Rotors Installed Before the Effective Date of This AD (g) For used turbine rotors installed on or after the effective date of this AD, and currently or
previously used in special-use operations:
(f) For turbine rotors installed before the effective date of this AD, and currently or previously (1) Before further flight, determine and record total equivalent cycles using paragraphs (f)(1)(i)
used in special-use operations: through (f)(1)(iii) of this AD.
(1) Within 100 major cycles-in-service after the effective date of this AD, or upon removal of the (2) Remove from service, turbine rotors affected by paragraph (g) of this AD using the
turbine rotor(s) from the engine, whichever occurs first, do the following: applicable Turbine Rotor Removal Schedule in Table A of this AD.
(i) Determine the total equivalent cycles accrued for turbine rotors. Use paragraph 2.A. of the
Accomplishment Instructions of the applicable Honeywell Alert Service Bulletin (ASB) for your New (Zero Cycles) Turbine Rotors Installed On or After the Effective Date of This AD
model engines listed in the following Table A, to make the determination.
(h) For all new (zero cycles) turbine rotors installed on or after the effective date of this AD used
TABLE A.—HONEYWELL ASBS FOR DETERMINING TOTAL EQUIVALENT CYCLES in special-use operations:
For engines Use ASB No. Turbine rotor removal (1) Use the new counting method by counting and recording minor and major cycles when
schedule accrued, and determine equivalent cycles by the method described in paragraphs (f)(1)(i) and
(A) TPE331–1 through –6 series TPE331–A72–2111, dated Use ASB Table 1. (f)(1)(iii) of this AD.
and TSE331–3U model. November 12, 2002 (2) Using the ratio of six takeoffs and landings per major cycle for unknown cycle history, as
(B) TPE331–8 through –9 series TPE331–A72–2123, dated February Use ASB table 1. referenced in paragraph (f)(1)(ii) of this AD, is not permitted.
8, 2006
Definitions
(C) TPE331–10 through–11 series TPE331–A72–2130, dated Use ASB Table 1.
September 27, 2005
(i) An engine used in special-use operations is defined as an engine that accrues major and minor
(D) TPE331–12 series TPE331–A72–2131, dated Use ASB Table 1.
cycles and is installed in an aircraft that makes multiple takeoffs and landings without engine
September 27, 2005
shutdown.
(ii) If you are unable to determine equivalent cycles for prior special-use operations due to the (j) Total equivalent cycles, is that combination of major and minor cycles as specified in the
absence of actual data regarding the number of takeoffs and landings per major cycle, you must use a Honeywell ASBs listed in Table A of this AD.
onetime ratio of six takeoffs and landings per major cycle to estimate prior special-use equivalent
cycles for each turbine rotor. (k) Total equivalent cycle life limits listed in the ASBs, are the cycle life limits specified in the
(iii) For each turbine rotor affected on the Life Limited Part Log Card, record the total equivalent SBs listed in Table B of this AD.
cycles accrued, as determined in paragraphs (f)(1)(i) and (f)(1)(ii) of this AD, by complying with the
recording requirements for your model engine listed in the following Table B: (l) The ''recording of total equivalent cycles on the Life Limited Part Log Card'' is that same
procedure specified for ''accumulated cycles'' or ''total cycles'' in the SBs listed in Table B of this AD.
7 8
(m) ''Turbine rotors'' include first, second, and third stage seal plates, air seals, rotor disks, Service Bulletin (SB) Page Revision Date
wheels, and assemblies, and are parts that have part numbers specified in the ASBs listed in Table A Honeywell SB No. TPE331–72–0180 (continued) 20 29 August 23, 2002.
of this AD. Total Pages: 54 21 31 November 7, 2003.
22–24 29 August 23, 2002.
(n) A major cycle is an engine start, takeoff, landing, and shutdown. 25 31 November 7, 2003.
26 29 August 23, 2002.
(o) A minor cycle, which occurs within a major cycle, is an additional landing with an engine 27–54 31 November 7, 2003.
speed reduction to ground idle with no engine shutdown followed by a takeoff.
Honeywell SB No. TPE331–72–0476 1–2 27 September 17, 2003.
Total pages: 46 3 25 May 24, 2002.
(p) A ''used turbine rotor'' is a turbine rotor whose cycles-since-new are more than zero.
4 27 September 17, 2003.
5 25 May 24, 2002.
Alternative Methods of Compliance
6 27 September 17, 2003.
(q) The Manager, Los Angeles Aircraft Certification Office, has the authority to approve 7–14 25 May 24, 2002.
alternative methods of compliance for this AD if requested using the procedures found in 14 CFR 15 26 July 26, 2002.
39.19. 16–22 25 May 24, 2002.
23–27 27 September 17, 2003.
Material Incorporated by Reference 28–32 25 May 24, 2002.
33 26 July 26, 2002.
(r) You must use the service information specified in Table C of this AD to perform the actions 34 25 May 24, 2002.
required by this AD. The Director of the Federal Register approved the incorporation by reference of 35 27 September 17, 2003.
the documents listed in Table C of this AD in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. 36 25 May 24, 2002.
Contact Honeywell Engines, Systems & Services, Technical Data Distribution, M/S 2101-201, P.O. 37–41 27 September 17, 2003.
Box 52170, Phoenix, AZ 85072-2170; telephone: (602) 365-2493 (General Aviation); (602) 365- 42 25 May 24, 2002.
5535 (Commercial); fax: (602) 365-5577 (General Aviation and Commercial) for a copy of this 43 27 September 17, 2003.
service information. You may review copies at the FAA, New England Region, Office of the 44 25 May 24, 2002.
Regional Counsel, 12 New England Executive Park, Burlington, MA; or at the National Archives and 45 27 September 17, 2003.
Records Administration (NARA). For information on the availability of this material at NARA, call 46 25 May 24, 2002.
202-741-6030, or go to: http://www.archives.gov/federal-register/cfr/ibr-locations.html. Alert Service Bulletin (ASB) Page Revision Date
Honeywell ASB No. TPE331–A72–2111 ALL Original November 12, 2002.
TABLE C.—INCORPORATION BY REFERENCE Total Pages: 12
Service Bulletin (SB) Page Revision Date Honeywell ASB No. TPE331–A72–2123 ALL Original February 8, 2006.
Honeywell SB No. TPE/TSE331–72–0019 1 22 May 16, 2001. Total Pages: 12
Total Pages: 16 2–11 21 March 3, 2000. Honeywell ASB No. TPE331–A72–2130 ALL Original September 27, 2005.
12 22 May 16, 2001. Total Pages: 16
13–16 21 March 3, 2000. Honeywell ASB No. TPE331–A72–2131 ALL Original September 27, 2005.
AlliedSignal SB No. TPE331–72–0117 1 11 November 13, 1997. Total Pages: 14
Total Pages: 10 2 9 May 24, 1995.
3–10 11 November 13, 1997. Issued in Burlington, Massachusetts, on June 26, 2006.
Honeywell SB No. TPE331–72–0180 1 31 November 7, 2003. Francis A. Favara,
Total Pages: 54 2–3 29 August 23, 2002. Manager, Engine and Propeller Directorate, Aircraft Certification Service.
4–5 31 November 7, 2003. [FR Doc. 06-5929 Filed 7-3-06; 8:45 am]
6–7 29 August 23, 2002. BILLING CODE 4910-13-P
8–13 31 November 7, 2003.
14 27 February 23, 2001.
15–17 31 November 7, 2003.
18 27 February 23, 2001.
19 31 November 7, 2003.
9 10
Alle erforderlichen Maßnahmen zur Abstellung des technischen Mangels müssen ordnungsgemäß,
Lufttüchtigkeitsanweisung vollständig und innerhalb der vorgesehen Fristen auf Basis der genannten Bezugsdokumente durchge-
LTA-Nr.: D-2006-236 führt werden. Alle Abweichungen von den Maßnahmen und Fristen dieser Lufttüchtigkeitsanweisung
bedürfen der vorherigen Zustimmung durch das Luftfahrt-Bundesamt.
Luftfahrt-Bundesamt
Datum der Bekanntgabe: 21.08.2006 Fristen:
Muster: Honeywell International AD der ausländischen Behörde: Alle anzuwendenden Fristen sind der oben genannten FAA Airworthiness Directive zu entnehmen.
TPE331 FAA AD 2006-15-08 Amdt. 39-14688 Die Laufzeit aller anzuwendenden Fristen beginnt mit dem Datum der Inkraftsetzung der genannten
FAA Airworthiness Directive.
Geräte-Nr.: Technische Mitteilungen des Herstellers:
7015, 7021 Honeywell Alert Service Bulletin (ASB) No. TPE331-A73-0271 Diese Lufttüchtigkeitsanweisung entspricht hinsichtlich der durchzuführenden Maßnahmen und Fristen der
Rev. 1 vom 25.01.2006 FAA AD 2006-15-08 Amdt. 39-14688
Honeywell ASB No. TPE331-A73-0254, Rev. 2 vom 17.06.2005 Durch die vorgenannten Mängel ist die Lufttüchtigkeit des Luftfahrtgerätes derart beeinträchtigt, daß es nach Ablauf der genannten Fristen
nur in Betrieb genommen werden darf, wenn die angeordneten Maßnahmen ordnungsgemäß durchgeführt worden sind. Im Interesse der
Honeywell ASB No. TPE331-A73-0262, Rev. 2 vom 17.06.2005 Sicherheit des Luftverkehrs, das in diesem Fall das Interesse des Adressaten am Aufschub der angeordneten Maßnahmen überwiegt, ist es
erforderlich, die sofortige Vollziehung dieser LTA anzuordnen.
Betroffenes Luftfahrtgerät: Rechtsbehelfsbelehrung:
Gegen diese Verfügung kann innerhalb eines Monats nach Bekanntgabe Widerspruch eingelegt werden. Der Widerspruch ist schriftlich oder
Honeywell International zur Niederschrift beim Luftfahrt-Bundesamt, Hermann-Blenk-Str. 26, 38108 Braunschweig einzulegen.
TPE331
LTAs werden auch im Internet unter http://www.lba.de publiziert
***
- Baureihen: TPE331-1
TPE331-2, -2UA
TPE331-3U, -3UW
TPE331-5, -5A, -5AB, -5B
TPE331-6, -6A
TPE331-10, -10AV, -10GP, -10GT, -10P, -10R, -10T, -10U
TPE331-10UA, -10UF, -10UG, -10UGR, -10UR
TPE331-11U
TPE331-12JR, -12UA, -12UAR, -12UHR
Hinweis:
Triebwerke dieser Baureihen wurden auch durch die Hersteller AlliedSignal Inc., Garrett
Engine Division, Garrett Turbine Engine Company und AiResearch Manufacturing
Company of Arizona produziert.
- Werk-Nrn.: Alle Triebwerke dieser Baureihen in denen folgende Kraftstoffregler installiert sind:
TPE331-1, -2 und -2UA:
Woodward ''Fuel Control Unit (FCU)'' mit den Hersteller-Teilenummern (P/N's)
869199-13/ -20/ -21/ -22/ -23/ -24/-25/ -26/ -27/ -28/ -29/ -31/ -32/ -33/ -34/ -35
TPE331-3U, -3UW, -5, -5A, -5AB, -5B, -6, -6A, -10AV, -10GP, -10GT, -10P und -10T:
Woodward ''Fuel Control Unit (FCU)'' mit den Hersteller-Teilenummern (P/N's)
893561-7/ -8/ -9/ -10/ -11/ -14/ -15/ -16/ -20/ -26/ -27/ -29
897770-1/ -3/ -7/ -9/ -10/ -11/ -12/ -14 / -15/ -16/ -25/ -26/ -28
TPE331-10, -10R, -10U, -10UA, -10UF, -10UG, -10UGR, -10UR, -11U, -12JR, -12UA, -
12UAR und -12UHR:
Woodward ''Fuel Control Unit (FCU)'' mit den Hersteller-Teilenummern (P/N's)
897375-2/ -3/ -4/ -5/ -8/ -9/ -10/ -11/ -12/ -13/ -14/ -15/ -16/ -17/ -19/ -21
897375-24/ -25/ -26/ -27
897780-1/ -2/ -3/ -4/ -5/ -6/ -7/ -8/ -9/ -10/ -11/ -14/ -15/ -16/ -17/ -18/ -19
897780-20/ -21/ -22/ -23/ -24/ -25/ -26/ -27/ -30/ -32/ -34/ -36/ -37/ -38
893561-17/ -18/ -19
Betrifft:
Möglicher Triebwerksausfall durch Überdrehzahl, Übertemperatur und ''Overtorque'' durch Ausfall des
Antriebs des Kraftstoffreglers.
Maßnahmen:
Detaillierte Informationen über die durchzuführenden Maßnahmen sind der oben genannten FAA
Airworthiness Directive und den genannten technischen Mitteilungen des Herstellers zu entnehmen.
Aktenzeichen: (10)T23-502.1/D-2006-236 Seite 1 von 2 Aktenzeichen: (10)T23-502.1/D-2006-236 Seite 2 von 2
[Federal Register: July 20, 2006 (Volume 71, Number 139)] Examining the AD Docket
[Rules and Regulations]
[Page 41121-41125] You may examine the docket that contains the AD, any comments received, and any final
From the Federal Register Online via GPO Access [wais.access.gpo.gov] disposition in person at the Docket Management Facility Docket Office between 9 a.m. and 5 p.m.,
[DOCID:fr20jy06-9] Monday through Friday, except Federal holidays. The Docket Office (telephone (800) 647-5227) is
–––––––––––––––––––––––––––––––––––- located on the plaza level of the Department of Transportation Nassif Building at the street address
DEPARTMENT OF TRANSPORTATION stated in ADDRESSES. Comments will be available in the AD docket shortly after the DMS receives
them.
Federal Aviation Administration
Comments
14 CFR Part 39
We provided the public the opportunity to participate in the development of this AD. We have
[Docket No. FAA-2006-23706; Directorate Identifier 2006-NE-03-AD; Amendment 39-14688; considered the comments received.
AD 2006-15-08]
Clarification of Discussion Paragraph
RIN 2120-AA64
Honeywell International Inc. points out that in the discussion section of the Notice of Proposed
Airworthiness Directives; Honeywell International Inc. TPE331 Series Turboprop Engines Rulemaking we stated that installation of an improved fuel control will eliminate the overspeed
condition by better accommodating a drive spline failure. Honeywell suggests that we change the
AGENCY: Federal Aviation Administration (FAA), Department of Transportation (DOT). discussion to state that replacing an affected fuel control assembly with an improved fuel control
assembly will only reduce the possibility of an overspeed, rather than eliminate it altogether. We
ACTION: Final rule. agree that Honeywell's suggestion has some logic from a risk management perspective. We recognize
that the improved fuel control may not eliminate the possibility of a drive spline failure or the
–––––––––––––––––––––––––––––––––––- resulting engine overspeed condition, but we intend that it will eliminate a destructive overspeed due
SUMMARY: The FAA is adopting a new airworthiness directive (AD) for Honeywell International to this spline failure. We have, however, changed paragraph (d) of the final rule (the statement of the
Inc. TPE331 series turboprop engines with certain part numbers of Woodward fuel control unit unsafe condition) to clarify that we expect that the AD will prevent destructive overspeed that could
(FCU) assemblies installed. This AD requires initial and repetitive dimensional inspections of the result in uncontained rotor failure, and damage to the airplane.
fuel control drive, for wear or damage. This AD results from reports of loss of the fuel control drive,
leading to engine overspeed, overtorque, overtemperature, uncontained rotor failure, and asymmetric Suggestion to Specifically Reference Pump Splines
thrust in multi-engine airplanes. We are issuing this AD to prevent destructive overspeed that could
result in uncontained rotor failure, and damage to the airplane. Honeywell International Inc. also suggests that we add the words ‘‘or pump'' after ‘‘fuel control''
in both paragraphs (f)(2) and (g)(2) of the proposed rule. Honeywell points out that the proposed
DATES: This AD becomes effective August 24, 2006. inspections also include the fuel pump spline as well as the fuel control splines. We agree that the
required inspections include the fuel pump spline and that if the fuel pump spline fails inspection, the
ADDRESSES: You can get the service information identified in this AD from Honeywell Engines, fuel pump would require repair or replacement. Therefore, we have added references to the fuel pump
Systems & Services, Technical Data Distribution, M/S 2101-201, P.O. Box 52170, Phoenix, AZ in paragraphs (f), (g), and (l) of the final rule. We have also split the repair and replace requirement in
85072-2170; telephone: (602) 365-2493 (General Aviation); (602) 365-5535 (Commercial); fax: paragraphs (f) and (g) into one sub-paragraph for the fuel pump, (f)(2) and (g)(2), and one for the fuel
(602) 365-5577 (General Aviation and Commercial). control assembly, (f)(3) and (g)(3), which we now refer to as the fuel control unit (FCU) assembly.
You may examine the AD docket on the Internet at http://dms.dot.gov or in Room PL-401 on the We made these changes to keep clear that the replacement requirements of the AD call for
plaza level of the Nassif Building, 400 Seventh Street, SW., Washington, DC. ‘‘modified'' FCU assemblies for multi-engine airplanes. Fuel pump assemblies whose splines fail
dimensional inspection may be replaced with serviceable fuel pump assemblies.
FOR FURTHER INFORMATION CONTACT: Joseph Costa, Aerospace Engineer, Los Angeles
Aircraft Certification Office, FAA, Transport Airplane Directorate, 3960 Paramount Blvd., Request To Add the Word ‘‘Governor''
Lakewood, CA 90712-4137; telephone (562) 627-5246; fax (562) 627-5210.
Honeywell International Inc. also requests that we add the word ‘‘governor'' to describe the
SUPPLEMENTARY INFORMATION: The FAA proposed to amend 14 CFR part 39 with a splined driveshafts between the fuel pump and the FCU. Honeywell points out that the proposal could
proposed airworthiness directive (AD). The proposed AD applies to Honeywell International Inc. be read so as not to include a required inspection of the quill shaft internal to the fuel control. We
TPE331 series turboprop engines with certain part numbers of Woodward FCU assemblies installed. agree, and have added a definition of the term ‘‘fuel control drive'' to paragraph (k) of the final rule
We published the proposed AD in the Federal Register on March 8, 2006 (71 FR 11546). That action that includes the change of ‘‘fuel control'' to ‘‘fuel control governor.''
proposed to require initial and repetitive dimensional inspections of the drive splines between the fuel
pump and fuel control governor, for wear or damage.
1 2
Claim That Destructive Overspeed Is Still Possible We do not agree that the AD needs to include mandatory instructions to the aircrew concerning
NTS. The commenter is correct that during flight with the modified FCU assembly installed, the
An FAA-approved repair station, Turbine Standard, Ltd, claims that destructive engine engine may experience NTS after failure of a fuel control drive. We believe that having the pilot shut
overspeed is really only possible on the ground with the prop ‘‘on the start locks'' and will continue to down the engine as soon as possible after drive spline failure by recognizing an unresponsive power
be possible with the new modified fuel control assembly. The commenter states that according to lever, consistent with the safe operation of the airplane, is the best action. We have changed
Honeywell's Operating Information Letters OI331-12R4, dated March 29, 2006, and OI331-18R2, paragraph (o) of the final rule to reference Honeywell's operating information letters.
dated March 29, 2006, the possibility of uncontained separation of the engine's high speed rotating
components still exists, at certain conditions. Furthermore, the commenter appears to question the Claim That the Modified FCU Assembly Is Not Necessary
need for this AD by pointing out that wear of the FCU and fuel pump drive can be adequately
managed by following the recommended maintenance program for the engine and that any FCUs that Lastly, Turbine Standard, Ltd claims that the modified FCU assembly is not necessary because
showed heavy spline wear were addressed by a previous AD, AD 94-26-07. of the propeller governor response to an engine overspeed, if the airplane is equipped with torque and
We do not agree. The proposed rule and this AD address a continuing problem that has caused temperature limiting (TTL) devices. The commenter believes that fuel bypassing the TTL devices
51 known incidents over the past 30 years. We believe that the fuel pump and fuel control spline and the propeller governor should maintain engine speed at its set point after a fuel control drive
failures represent a serious unsafe condition that requires mandatory inspections and replacement of failure.
existing fuel control designs to warrant AD action rather than reliance on recommended maintenance We do not agree. Engine testing shows that the TTL devices cannot bypass sufficient fuel and
practices. Even after issuing AD 94-26-07, we continue to receive reports of fuel control drive the propeller governor cannot maintain speed consistently enough to ensure a safe operation of the
failures, overspeed, and destructive overspeed events. With a modified FCU installed, AD 94-26-07 TPE331 engine. In addition, since the TTL devices are optional devices for some aircraft, the TTL's
will no longer apply. marginal and temporary benefit is not a safe alternative.
Whether destructive overspeeds will continue to be possible with the new modified fuel control
assembly, we recognize that this failure condition is rare and only exists under certain high- Conclusion
temperature and high-altitude ground start conditions, with certain older design engines while the
prop is ‘‘on the locks''. When this set of rare conditions is coupled with the fuel control drive low We have carefully reviewed the available data, including the comments received, and determined
failure rate, a destructive overspeed is improbable. We consider the modified FCU assembly to be that air safety and the public interest require adopting the AD with the changes described previously.
safe. We have determined that these changes will neither increase the economic burden on any operator
nor increase the scope of the AD.
Claim That Asymmetric Thrust Would be More Prevalent
Costs of Compliance
Turbine Standard, Ltd also claims that the modified fuel control assembly installed on an engine
on a multi-engine airplane would actually make asymmetric thrust more likely in the event of a fuel We estimate this AD will affect 3,250 engines installed on airplanes of U.S. registry. We also
pump or fuel control drive spline failure. The commenter explains that after the failure of a fuel estimate it will take about one work-hour per engine to replace the FCU assembly during a normal
control drive on a modified fuel control assembly, the modified fuel control would deliver only 180 scheduled overhaul. We also estimate it will take about three work-hours to perform a dimensional
PPH of fuel flow, which is below flight idle fuel flow. Since fuel flows for take off thrust are inspection of the fuel control drive. The average labor rate is $65 per work-hour. A replacement FCU
normally very high and the failure mode of an unmodified fuel control unit typically delivers more assembly will cost about $9,700 per engine. We estimate that on each engine, one FCU assembly
fuel flow, the commenter concludes that the aircrew would be in a worse situation with a modified inspection will be performed, and each engine will have the FCU assembly replaced. Based on these
fuel control after suffering drive spline failure than with a non-modified fuel control. figures, we estimate the total cost of the AD to U.S. operators to be $32,370,000.
We do not agree. While it is true that the fuel flow after drive spline failure with a modified fuel The Agency is committed to updating the aviation community of expected costs associated with
control unit may result in a more pronounced asymmetric thrust condition at takeoff, we believe that the MU-2B series airplane safety evaluation conducted in 2005. As a result of that commitment, the
after considering all ground and flight conditions, the modified FCU assembly is much safer than the accumulating expected costs of all ADs related to the MU-2B series airplane safety evaluation may be
applicable FCU assembly on the multi-engine aircraft. In addition, with a modified fuel control, the found at the following Web site:
failure mode would produce a clearly evident decrease in thrust that a trained aircrew can easily http://www.faa.gov/aircraft/air_cert/design_approvals/small_airplanes/cos/mu2_foia_reading_library/.
recognize and safely handle, even on takeoff.
Authority for This Rulemaking
AD Does Not Address Recommendations to the Pilot on Negative Torque Sensing
Title 49 of the United States Code specifies the FAA's authority to issue rules on aviation safety.
Turbine Standard, Ltd also claims that the proposed AD does not address recommendations to Subtitle I, Section 106, describes the authority of the FAA Administrator. Subtitle VII, Aviation
the pilot if the engine starts to experience ‘‘negative torque sensing'' during flight. The commenter Programs, describes in more detail the scope of the Agency's authority.
reasons that after the failure of a fuel control drive spline, the modified fuel control assembly will We are issuing this rulemaking under the authority described in Subtitle VII, Part A, Subpart III,
deliver 180 PPH of fuel flow, which may be below flight idle fuel flow, and the engine may Section 44701, ‘‘General requirements.'' Under that section, Congress charges the FAA with
experience negative torque sensing (NTS). In addition, ‘‘negative torque sensing'' at higher than promoting safe flight of civil aircraft in air commerce by prescribing regulations for practices,
normal engine speeds for long periods, might damage the propeller. methods, and procedures the Administrator finds necessary for safety in air commerce. This
regulation is within the scope of that authority because it addresses an unsafe condition that is likely
to exist or develop on products identified in this rulemaking action.
3 4
