SAIB NE-08-49

FAA Aircraft Certification Service

SPECIAL AIRWORTHINESS

INFORMATION BULLETIN SAIB: NE-08-49 SUBJ: Turbine Engine Combustion Section Date: September 9, 2008 This is information only. Recommendations aren’t mandatory.

Introduction

This Special Airworthiness Information Bulletin (SAIB) alerts you, owners, operators, and certificated repair facilities of General Electric (GE) CJ610 series turbojet and CF700 series turbofan engines of the potential for premature distress or failure of combustion liner inner shells, part number (P/N) AFT-5016T30G02. These combustion liner inner shells are a subassembly of several GE combustion liner assemblies with different P/Ns. These combustion liner inner shells were manufactured by AFT Technologies, 29-10 37 Ave, Long Island City, New York 11101, under Parts Manufacturer Approval. At this time, this airworthiness concern isn’t an unsafe condition that would warrant airworthiness directive action under Title 14 of the Code of Federal Regulations (14 CFR) part 39.

Background

A GE CJ610-8A turbojet engine experienced major cracking of the combustion liner inner shell P/N AFT-5016T30G02 that had 670.3 hours-since-new. The cracking resulted in the liberation of a section of the liner assembly, which caused damage to the engine turbine. Several other AFT- manufactured combustion liner inner shells that were removed from service as a precautionary measure have also exhibited major and/ or minor cracking at engine times ranging from 248 hours (8 louvers with minor and major cracks) to 929 hours (2 louvers beginning to crack). However, some AFT-manufactured combustion liner inner shells are still in service and have accumulated between about 250 to 1,500 hours-since-new.

Recommendation

In order to prevent the possible premature engine failure due to liberation of a section of combustion liner inner shell, P/N AFT-5016T30G02, we recommend that you borescope GE CJ610/CF700 engines with a combustion liner inner shell, P/N AFT-5016T30G02, installed, at intervals not to exceed 250 hours. Since neither the aircraft nor engine manuals have engine borescope procedures, contact your local aircraft or engine manufacturer’s representative for assistance.

For Further Information Contact

Norm Perenson, Aerospace Engineer, NYACO, FAA, Engine and Propeller Directorate, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; e-mail: norman.perenson@faa.gov;

telephone: (516) 228-7337; fax: (516) 794-5531.