AD 2007-21-05 Airworthiness Directives; International Aero Engines (IAE) V2500 Series Turbofan Engines

This AD applies to International Aero Engines (IAE) model V2500-A1, V2522-A5, V2524-A5, V2527-A5, V2527E-A5, V2527M-A5, V2530-A5, V2533-A5, V2525-D5, and V2528-D5 turbofan engines with high pressure turbine (HPT) stage 2 air seals, part numbers (P/Ns) 2A0487, 2A1159, 2A1160, 2A3108, 2A3179, 2A3185, 2A3425, and 2A3596, installed. These engines are installed on, but not limited to, Airbus A319, A320, A321, and Boeing MD-90 airplanes.

You are responsible for having the actions required by this AD performed within the compliance times specified unless the actions have already been done. Monitoring N2 Vibration on All IAE Model V2500-A1 and V2522-A5, V2524-A5, V2527-A5, V2527E-A5, V2527M-A5, V2530-A5, and V2533-A5 Engines (f) For IAE model V2530-A5 and V2533-A5 engines operated at 30,000 or 33,000 pounds of thrust, or for model V2522-A5, V2524-A5, V2527-A5, V2527E-A5, and V2527M-A5 engines that have ever operated in the 30,000 or 33,000 pound thrust range, begin monitoring for N2 vibration trend if the HPT stage 2 air seal reaches 4,000 cycles-since-new (CSN) or more. (g) For IAE model V2500-A1 and V2522-A5, V2524-A5, V2527-A5, V2527E-A5, and V2527M-A5 engines operated below 30,000 pounds of thrust, begin monitoring for N2 vibration trend if the HPT stage 2 air seal reaches 6,000 CSN. (h) Monitor N2 vibration trend of each engine for every 100 to 150 cycles of engine operation as follows: (1) Use the Accomplishment Instructions of IAE Service Bulletin (SB) V2500-ENG-72-0500, Revision 1, dated July 14, 2006, to gather and monitor steady-state cruise N2 vibration data. (2) For a trend that has a slope of 0.001 units per cycle or greater and less than 0.003 units per cycle, remove the seal 250 cycles from the point at which the slope begins to increase and do not reinstall it in any V2500 engine. (3) For a trend that has a slope of 0.003 units per cycle or greater, remove the seal in 10 cycles and do not reinstall it in any V2500 engine. (4) If a through crack is found in the front fillet radius of the HPT stage 2 air seal, remove the following: (i) For the A1 model engine, remove the HPT stage 1 and 2 disks and HPT stage 1 rear air seals (64 per engine) and do not reinstall them in any V2500 engine. (ii) For all A5 engine models, remove the HPT stage 1 disk and the HPT stage 1 rear air seals (64 per engine) and do not reinstall them in any V2500 engine. (5) Use Section 3, Accomplishment Instructions, of IAE SB V2500-ENG-72-0502, Revision 1, dated March 15, 2006, for removal procedures. Monitoring N2 Vibration on All IAE Model V2525-D5 and V2528-D5 Engines (i) For all IAE model V2500-D5 series engines, begin monitoring for N2 vibration trend if the HPT stage 2 air seal reaches 6,000 CSN or more. (j) Monitor N2 vibration trend of each engine for every 100 to 150 cycles of engine operation as follows: (1) Use Section 3, Accomplishment Instructions, of IAE SB V2500-ENG-72-0501, Revision 1, dated July 14, 2006, to gather and monitor the steady-state cruise N2 vibration data. (2) If an increasing trend that has a slope of 0.0007 units per cycle or greater, and less than 0.002 units per cycle is observed, remove the HPT stage 2 air seal within 250 cycles from the point at which the slope begins to increase and do not reinstall it in any V2500 engine. (3) If an increasing trend that has a slope of 0.002 units per cycle or greater is observed, remove the HPT stage 2 air seal within 10 cycles and do not reinstall it in any V2500 engine. (4) If a through crack is found in the front fillet radius of the HPT stage 2 air seal of D5 model engines, remove the HPT stage 1 disk and HPT rear air seals (64 per engine) and do not reinstall them in any V2500 engine. (5) Use Section 3, Accomplishment Instructions, of IAE SB V2500-ENG-72-0502, dated March 15, 2006, for removal procedures. Removal of HPT Stage 2 Air Seals at Opportunity (k) For all engines, when the HPT stage 2 air seal reaches 2,000 CSN, remove the HPT stage 2 air seal at the next separation of the HPT stage 1 and 2 rotors and do not reinstall it in any V2500 engine. Definition (l) For the purposes of this AD, “At Opportunity” is defined as when the engine is disassembled, the HPT stage 2 seal is exposed, and the HPT stage 1 and 2 rotors are separated after 2,000 CSN. (m) The Accomplishment Instructions of IAE SB V2500-ENG-72-0502, Revision 1, dated March 15, 2006, provide information on removing the HPT stage 2 air seal. Alternative Methods of

This AD results from a report that HPT stage 2 air seals have developed cracks. We are issuing this AD to prevent uncontained failure of the HPT stage 2 air seal.