AD 2004-20-01

The FAA is adopting 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 AD requires 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 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.

Final rule.

2004-20-01 Pratt & Whitney Canada: Amendment 39-13806. Docket No. 2003-NE-35-AD.

Effective Date

(a) This AD becomes effective November 5, 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) Compliance with this AD is required as indicated, unless already 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.

Material Incorporated by Reference

(j) You must use Honeywell Service Information Bulletin No. 82, dated September 14, 2001, to perform the inspections required by this AD. The Director of the Federal Register approved the incorporation by reference of this service bulletin in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. You can get a copy from Honeywell Engines & Systems, Technical Publications Department, 111 South 34th Street, Phoenix, Arizona 85034; telephone (602) 365-5535; fax (602) 365-5577. You can review copies at FAA, New England Region, Office of the Regional Counsel, 12 New England Executive Park, Burlington, MA, or at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, call 202-741-6030, or go to: http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html .

Related Information

(k) None.

The FAA proposed to amend 14 CFR part 39 with a proposed AD. The proposed AD applies to PWC models PW123, PW123B, PW123C, PW123D, PW123E, PW123AF, PW124B, PW125B, PW126A, PW127, PW127E, PW127F, and PW127G turboprop engines. We published the proposed AD in the Federal Register on December 10, 2003 (68 FR 68802). That action proposed to 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.

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.

Comments

We provided the public the opportunity to participate in the development of this AD. We received no comments on the proposal or on the determination of the cost to the public.

Conclusion

We have carefully reviewed the available data and determined that air safety and the public interest require adopting the AD as proposed.

Costs of Compliance

There are about 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 will be affected by this AD. We also estimate that it will take about 0.1 work hour per engine to perform the 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 will cost about $72,000 per engine. Based on these figures, we estimate the total cost of the 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 replacedat shop visit, no additional labor costs will be incurred.

Regulatory Findings

We have determined that this AD will not have federalism implications under Executive Order 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 various levels of government.

For the reasons discussed above, I certify that this AD:

(1) Is not a "significant regulatory action" under Executive Order 12866;

(2) Is not a "significant rule" under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and

(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. You may get a copy of this summary by sending a request tous 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, Incorporation by reference, Safety.

Adoption of the Amendment

Accordingly, under the authority delegated to me by the Administrator, the Federal Aviation Administration amends 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.

39.13 [Amended]

2. The FAA amends 39.13 by adding the following new airworthiness directive (AD):