2003-05-10R1 General Electric Company: Amendment 39-13337. Docket No. 2001-NE-21-AD. Revises AD 2003-05-10, Amendment 39-13086.
Applicability
This airworthiness directive (AD) applies to General Electric Company (GE) CF34-3A1, -3B, and -3B1 turbofan engines with scavenge screens part numbers (P/Ns) 4047T95P01 and 5054T86G02 installed in the B-sump oil scavenge system. These engines are installed on, but not limited to, Bombardier Inc. (Canadair) Model CL-600-2A12, CL-600-2B16, and CL-600-2B19 airplanes.
Note 1: This 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
Compliance with this AD is required as indicated, unless already done.
To prevent B-sump scavenge screen blockage due to coking, which could result in ignition of B-sump oil in the secondary air system, fan drive shaft separation, and uncontained engine failure, do the following:
Initial Inspection and Cleaning of B-Sump Screens
(a) Perform an initial visual inspection and cleaning of scavenge screens, P/Ns 4047T95P01 and 5054T86G02, installed in the B-sump oil scavenge system, in accordance with Paragraphs 3A through 3B of the Accomplishment Instructions of GE Aircraft Engines (GE) Alert Service Bulletin (ASB) CF34-AL S/B 79-A0014, Revision 3, dated January 31, 2003; or ASB CF34-BJ S/B 79-A0015, Revision3, dated January 31, 2003; and the following table:
Initial Inspection and Cleaning Schedule
Engine hours time-since-new (TSN) or time-since-last-shop-visit (TSLSV)
Inspect and clean
(1) Fewer than 4,000 hours TSN or fewer than 4,000 hours TSLSV if it can be confirmed that both the B-sump scavenge screens were cleaned and the B-sump and combustor frame (strut tubes) were removed from the engine and cleaned at that prior shop visit.
Before 4,000 hours TSN or TSLSV.
(2) Fewer than 1,000 hours TSLSV if it can NOT be confirmed that both the B-sump scavenge screens were cleaned and the B-sump and combustor frame (strut tubes) were removed from the engine and cleaned at that prior shop visit.
Before 1,000 hours TSLSV.
(3) 4,000 hours or greater TSN or 4,000 hours or greater TSLSV if it can be confirmed that both the B-sump scavenge screens were cleaned and the B-sump and combustor frame (strut tubes) were removed from the engine and cleaned at that prior shop visit, or 1,000hours or greater TSLSV if it can NOT be confirmed that both the B-sump and combustor frame (strut tubes) were removed from the engine and cleaned at that prior shop visit.
Within 500 hours time-in-service (TIS) after the effective date of this AD.
Repetitive Inspections and Cleaning
(b) Perform repetitive visual inspections and cleaning of scavenge screens, P/Ns 4047T95P01 and 5054T86G02, installed in the B-sump oil scavenge system, in accordance with Paragraphs 3A through 3B of the Accomplishment Instructions of GE ASB CF34-AL S/B 79-A0014, Revision 3, dated January 31, 2003; and ASB CF34-BJ S/B 79-A0015, Revision 3, dated January 31, 2003; and the following:
(1) At intervals not to exceed 200 hours time-since-last-inspection (TSLI), if no coke is found in screens during initial or any prior inspections, or
(2) At intervals not to exceed 100 hours TSLI, if coke is found in screens during initial or any prior inspections.
Terminating Actions
(c) Install newscreenless fittings or fittings that have been reworked to remove the screens, in the B-sump oil scavenge system, in accordance with GE ASB CF34-AL S/B 79-A0016, dated June 17, 2002; or ASB CF34-BJ S/B 79-A0017, dated June 17, 2002, and the following schedule:
(1) For engines with more than 4,000 hours TSN, within 500 hours TIS after the effective date of this AD, or within 1,000 hours TSLSV, whichever occurs first.
(2) For engines with less than or equal to 4,000 hours TSN, prior to 4,500 hours TSN.
This constitutes terminating action to the inspections required in paragraph (b) of this AD.
Alternative Methods of Compliance
(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, Engine Certification Office (ECO). Operators must submit their request through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, ECO.
Note 2: Information concerning the existence of approved alternative methods of compliance with this airworthiness directive, if any, may be obtained from the ECO.
Special Flight Permits
(e) Special flight permits may be issued in accordance with 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 done.
Documents That Have Been Incorporated by Reference
(f) The actions must be done in accordance with the following General Electric Company Alert Service Bulletins (ASB):
Document No.
Pages
Revision
Date
ASB CF34-AL S/B 79-A0014
Total Pages: 10
All
3
January 31, 2003.
ASB CF34-BJ S/B 79-A0015
Total Pages: 9
All
3
January 31, 2003.
ASB CF34-AL S/B 79-A0016
Total Pages: 12
All
Original
June 17, 2002.
ASB CF34-BJ S/B 79-A0017
Total Pages: 11
All
Original
June 17, 2002.
This incorporation by reference of General ElectricAlert Service Bulletin (ASB) CF34-AL S/B 79-A0014, Revision 3, dated January 31, 2003; ASB CF34-BJ S/B 79-A0015, Revision 3, dated January 31, 2003; GE ASB CF34-AL S/B 79-A0016 and ASB CF34-BJ S/B 79-A0017, both dated June 17, 2002, was approved by the Director of the Federal Register on April 2, 2003, (68 FR 12086; March 18, 2003) in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be obtained from GE Aircraft Engines, 1000 Western Avenue, Lynn, MA 01910; Attention: CF34 Product Support Engineering, Mail Zone: 34017; telephone (781) 594-6323; fax (781) 594-0600. Copies may be inspected at the FAA, New England Region, Office of the Regional Counsel, 12 New England Executive Park, Burlington, MA; or at the Office of the Federal Register, 800 North Capitol Street, NW, suite 700, Washington, DC.
Effective Date
(g) This amendment becomes effective on November 18, 2003.