[Federal Register Volume 68, Number 237 (Wednesday, December 10, 2003)]
[Proposed Rules]
[Pages 68802-68804]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 03-30587]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2003-NE-35-AD]
RIN 2120-AA64


Airworthiness Directives; Pratt & Whitney Canada Models PW123, 
PW123B, PW123C, PW123D, PW123E, PW123AF, PW124B, PW125B, PW126A, PW127, 
PW127E, PW127F, and PW127G Turboprop Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD) 
for Pratt & Whitney Canada (PWC) models PW123, PW123B, PW123C, PW123D, 
PW123E, PW123AF, PW124B, PW125B, PW126A, PW127, PW127E, PW127F, and 
PW127G turboprop engines. This proposed AD would require initial and 
repetitive gap inspections of the bypass valve cover, on certain part 
number (P/N) mechanical fuel controls (MFCs), and replacement of those 
MFCs as mandatory terminating action to the repetitive inspections. 
This proposed AD is prompted by sixteen reports of loss of engine 
throttle response and overspeed, eight of which resulted in in-flight 
shutdown. We are proposing this AD to prevent loss of throttle response 
and overspeed, resulting in engine in-flight shutdown.

DATES: We must receive any comments on this proposed AD by February 9, 
2004.

ADDRESSES: Use one of the following addresses to submit comments on 
this proposed AD:
    [sbull] By mail: Federal Aviation Administration (FAA), New England 
Region, Office of the Regional Counsel, Attention: Rules Docket No. 
2003-NE-35-AD, 12 New England Executive Park, Burlington, MA 01803-
5299.
    [sbull] By fax: (781) 238-7055.
    [sbull] By e-mail: [email protected].
    You can get the service information identified in this proposed AD 
from Honeywell Engines & Systems, Technical Publications Department, 
111 South 34th Street, Phoenix, Arizona 85034; telephone (602) 365-
5535; fax (602) 365-5577.
    You may examine the AD docket, by appointment, at the FAA, New 
England Region, Office of the Regional Counsel, 12 New England 
Executive Park, Burlington, MA.

FOR FURTHER INFORMATION CONTACT: Ian Dargin, Aerospace Engineer, Engine 
Certification Office, FAA, Engine and Propeller Directorate, 12 New 
England Executive Park, Burlington, MA 01803-5299; telephone (781) 238-
7178; fax (781) 238-7199.

SUPPLEMENTARY INFORMATION:

Comments Invited

    We invite you to submit any written relevant data, views, or 
arguments regarding this proposal. Send your comments to an address 
listed under ADDRESSES. Include ``AD Docket No. 2003-NE-35-AD'' in the 
subject line of your comments. If you want us to acknowledge receipt of 
your mailed comments, send us a self-addressed, stamped postcard with 
the docket number written on it; we will date-stamp your postcard and 
mail it back to you. We specifically invite comments on the overall 
regulatory, economic, environmental, and energy aspects of the proposed 
AD. If a person contacts us verbally, and that contact relates to a 
substantive part of this proposed AD, we will summarize the contact and 
place the summary in the docket. We will consider all comments received 
by the closing date and may amend the proposed AD in light of those 
comments.
    We are reviewing the writing style we currently use in regulatory 
documents. We are interested in your comments on whether the style of 
this document is clear, and your suggestions to improve the clarity of 
our communications that affect you. You may get more information about 
plain language at http://www.faa.gov/language and http://www.plainlanguage.gov.

Examining the AD Docket

    You may examine the AD Docket (including any comments and service 
information), by appointment, between 8 a.m. and 4:30 p.m., Monday 
through Friday, except Federal holidays. See ADDRESSES for the 
location.

Discussion

    Transport Canada, which is the airworthiness authority for Canada, 
recently notified the FAA that an unsafe condition may exist on PWC 
models PW123, PW123B, PW123C, PW123D, PW123E, PW123AF, PW124B, PW125B, 
PW126A, PW127, PW127E, PW127F, and PW127G turboprop engines. Transport 
Canada advises that sixteen reports of loss of engine throttle response 
and overspeed have been received, eight of which resulted in in-flight 
shutdown. Investigation by the manufacturer revealed that the cause of 
this problem is dislodgement of the outer lip of the mechanical fuel 
control bypass valve diaphragm. The dislodgement is caused by 
inadequate preload applied to the bypass valve diaphragm outer lip 
during the assembly of the MFC.

Relevant Service Information

    We have reviewed and approved the technical contents of Honeywell 
Service Information Bulletin (SIB) No. 82, dated September 14, 2001, 
that describes procedures for detecting dislodgement of the outer lip 
of the MFC bypass valve diaphragm, by performing gap inspections of the 
bypass valve cover on affected MFCs.

Differences Between This Proposed AD and the Manufacturer's Service 
Information

    Although Honeywell SIB No. 82, dated September 14, 2001, suggests 
the gap inspections be done periodically at the aircraft ``A'' check, 
this proposal requires initial gap inspections within 500 hours time-
in-service (TIS) after the effective date of the proposed AD, and 
repetitive gap inspections at intervals of 1,500 hours TIS. This 
proposal also requires replacement of the MFC with an MFC that has an 
improved design bypass valve diaphragm.

FAA's Determination and Requirements of the Proposed AD

    These PWC models PW123, PW123B, PW123C, PW123D, PW123E, PW123AF, 
PW124B, PW125B, PW126A, PW127, PW127E, PW127F, and PW127G turboprop 
engines, manufactured in Canada, are type-certificated for operation in 
the United States under the provisions of section 21.29 of the Federal 
Aviation Regulations (14 CFR 21.29) and the applicable bilateral 
airworthiness agreement. Pursuant to this bilateral airworthiness 
agreement,

[[Page 68803]]

Transport Canada has kept us informed of the situation described above. 
We have examined Transport Canada's findings, reviewed all available 
information, and determined that AD action is necessary for products of 
this type design that are certificated for operation in the United 
States. Therefore, we are proposing this AD, which would require:
    [sbull] Initial gap inspection of the bypass valve cover on 
affected MFCs, within 500 hours time-in-service (TIS) after the 
effective date of the proposed AD.
    [sbull] Repetitive gap inspections of the bypass valve cover on 
affected MFCs, at intervals of 1,500 hours TIS.
    [sbull] Replacement of the affected MFC with an MFC that has an 
improved design bypass valve diaphragm, within 4,500 hours-in-service 
or 24 months from the effective date of this AD, whichever occurs 
first, as mandatory terminating action to the repetitive inspections of 
the proposed AD.
    The proposed AD would require you to use the service information 
described previously to perform the inspections.

Changes to 14 CFR Part 39--Effect on the Proposed AD

    On July 10, 2002, we issued a new version of 14 CFR part 39 (67 FR 
47998, July 22, 2002), which governs the FAA's AD system. This 
regulation now includes material that relates to altered products, 
special flight permits, and alternative methods of compliance. This 
material previously was included in each individual AD. Since this 
material is included in 14 CFR part 39, we will not include it in 
future AD actions.

Costs of Compliance

    There are approximately 2,800 PWC models PW123, PW123B, PW123C, 
PW123D, PW123E, PW123AF, PW124B, PW125B, PW126A, PW127, PW127E, PW127F, 
and PW127G turboprop engines of the affected design in the worldwide 
fleet. We estimate that 473 engines installed on airplanes of U.S. 
registry would be affected by this proposed AD. We also estimate that 
it would take about 0.1 work hour per engine to perform the proposed 
inspection, about 1 work hour per engine to replace the MFC during 
maintenance, and that the average labor rate is $65 per work hour. 
Required parts would cost approximately $72,000 per engine. Based on 
these figures, we estimate the total cost of the proposed AD to U.S. 
operators to be $34,089,819. The manufacturer has stated that it may 
provide the new design MFCs at no cost to operators, and that if the 
MFC is replaced at shop visit, no additional labor costs will be 
incurred.

Regulatory Findings

    We have determined that this proposed AD would not have federalism 
implications under Executive Order 13132. This proposed AD 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.
    For the reasons discussed above, I certify that the proposed 
regulation:
    1. Is not a ``significant regulatory action'' under Executive Order 
12866;
    2. Is not a ``significant rule'' under the DOT Regulatory Policies 
and Procedures (44 FR 11034, February 26, 1979); and
    3. Would 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 proposal and 
placed it in the AD Docket. You may get a copy of this summary by 
sending a request to us at the address listed under ADDRESSES. Include 
``AD Docket No. 2003-NE-35-AD'' in your request.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Safety.

The Proposed Amendment

    Accordingly, under the authority delegated to me by the 
Administrator, the Federal Aviation Administration proposes to amend 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. The FAA amends Sec.  39.13 by adding the following new 
airworthiness directive:

Pratt & Whitney Canada: Docket No. 2003-NE-35-AD.

Comments Due Date

    (a) The FAA must receive comments on this airworthiness 
directive (AD) action by February 9, 2004.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to Pratt & Whitney Canada (PWC) models 
PW123, PW123B, PW123C, PW123D, PW123E, PW123AF, PW124B, PW125B, 
PW126A, PW127, PW127E, PW127F, and PW127G turboprop engines, with 
mechanical fuel controls (MFCs), part numbers (P/Ns) 3244841-21, 
3244853-17, 3244855-15, 3244857-14, 3244858-23, 3244871-5, 3244873-
4, and 3244874-4, installed. These engines are installed on, but not 
limited to, Aerospatiale ATR 42 and ATR 72, BAE Systems (Operations) 
Limited ATP, Bombardier Inc. DHC-8-200 series, DHC-8-300 series, CL-
215T, and CL-415, Construcciones Aeronauticas, S.A. (CASA) C-295, 
Fokker Aircraft B.V. F27 Mark 050, and Mark 060 airplanes.

Unsafe Condition

    (d) This AD is prompted by sixteen reports of loss of engine 
throttle response and overspeed, eight of which resulted in in-
flight shutdown. We are issuing this AD to prevent loss of throttle 
response and overspeed, resulting in engine in-flight shutdown.

Compliance

    (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.

Initial Gap Inspection

    (f) Within 500 hours time-in-service (TIS) after the effective 
date of the AD, perform a gap inspection between the MFC bypass 
valve cover and the MFC main body, and disposition the MFC. Follow 
paragraphs 5.0 through 5.3 of Honeywell Service Information Bulletin 
(SIB) No. 82, dated September 14, 2001, to do the inspection and MFC 
disposition.

Repetitive Gap Inspections

    (g) At intervals of 1,500 hours TIS from the last gap 
inspection, perform repetitive gap inspections between the MFC 
bypass valve cover and the MFC main body and disposition the MFC. 
Follow paragraphs 5.0 through 5.3 of Honeywell SIB No. 82, dated 
September 14, 2001, to do the inspection and MFC disposition.

Mandatory Terminating Action

    (h) Within 4,500 hours TIS or 24 months from the effective date 
of this AD, whichever occurs first, replace the MFC with an MFC not 
having a P/N listed in paragraph (c) of this AD.
    (i) Replacement of the MFC with an MFC whose P/N is not listed 
in paragraph (c) of this AD constitutes mandatory terminating action 
to the repetitive inspection requirements specified in paragraph (g) 
of this AD. Information on new design replacement MFCs can be found 
in PWC Service Bulletin No. PW100-72-21562, Revision 2, dated 
December 7, 2000.

Alternative Methods of Compliance

    (j) The Manager, Engine Certification Office, has the authority 
to approve alternative methods of compliance for this AD if 
requested using the procedures found in 14 CFR 39.19.

Material Incorporated by Reference

    (k) You must use Honeywell Service Information Bulletin No. 82, 
dated September 14, 2001, to perform the inspections required

[[Page 68804]]

by this AD. Approval of incorporation by reference from the Office 
of the Federal Register is pending.

Related Information

    (l) Transport Canada airworthiness directive CF-2002-34, dated 
July 15, 2002, and Pratt & Whitney Service Bulletin No. PW100-72-
21669, dated October 2, 2001, also address the subject of this AD.

    Issued in Burlington, Massachusetts, on December 4, 2003.
Jay J. Pardee,
Manager, Engine and Propeller Directorate, Aircraft Certification 
Service.
[FR Doc. 03-30587 Filed 12-9-03; 8:45 am]
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