Lycoming Piston Engines AD/LYC/97 Connecting Rod Bolt Inspection 6/95 DM Applicability: The following Textron Lycoming reciprocating engine models, assembled on or after 15 February 1994, and that contain connecting rod bolts shipped directly or indirectly from Superior Air Parts, Inc., on or after 15 February 1994: O-360-A1A, -A1AD, -A1C, -A1D, -A1F6, -A1F6D, -A1G6, -A1G6D, -A1LD, -A2A, -A2D, -A2E, -A2F, -A2G, -A3A, -A3AD, -A4A, -A4G, -A4J, -A4K, -A4M, -A4N, -A5AD, -B2A, -C1A, -C1C, -C1E, -C1F, -C1G, -C2A, -C2C, -C2D, -C2E, -D2A, -D2B, and -F1A6; IO-360-A1A, -A1B, -A1B6, -A1B6D, -A1C, -A1D, -A1D6, -A2A, -A2B, -A3B6D, -B1A, -B1B, -B1D, -B1E, -B1F, -B2F, -B2F6, -B4A, -C1A, -C1B, -C1C6, -C1D6, -C1E6, -C1F, and -J1A6D; AIO-360-A1A, -A1B, and -B1B; LO-360-A1G6D; HO-360-B1A, and -B1B; HIO-360-A1A, -B1A, -C1A, -C1B, -E1AD, and -E1BD; LIO-360-C1E6; TIO-360-A1B; AEIO-360-A1E, -B1G6, and -H1A; O-540-A1A, -A1A5, -A1B5, A1C5, -A1D, -A1D5, -A2B, -A3D5, -B1A5, -B1B5, -B2B5, -B2C5, -B4B5, -E4A5, -E4B5, -E4C5, -F1A5, -F1B5, -G1A5, -G2A5, -H1B5D, -H2B5D, J1A5D, -J3A5D, -J3C5D, and -L3C5D; IO-540-A1A5, -B1A5, -B1C5, -C1B5, -C4B5, -C4C5, -C4D5D, -D4A5, -E1A5, -E1B5, -G1A5, -G1B5, -G1C5, -G1D5, -G1E5, -G1F5, -J4A5, -K1A5, -K1A5D, -K1B5, -K1C5, -K1D5, -K1E5, -K1K5, -M1A5, -N1A5, -P1A5, -R1A5, -T4C5D, -K1F5, -K1F5D, -K1G5, -K1G5D, -K1J5D, -K1K5, -M1QA5, -M1B5D, -N1A5, -P1A5, -R1A5, -S1A5, -T4A5D, -T4B5D, -T4CTD, -V4A5D, -W1A5D, -W3A5D, and -AA1A5; TIO-540-A1A, -A1B, -A2A, -A2B, -A2C, -C1A, -E1A, -G1A, -H1A, -J2B, -F2BD, -J2BD, -N2BD, -R2AD, -S1AD, -AA1AD, and -AB1AD; LTIO-540-J2B, -F2BD, -J2BD, -N2BD, and -R2AD; IVO-540-A1A; AEIO-540-D4B5; TIO-541-A1A, E1A4, -E1B4, and -E1C4; COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 106 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES IO-720-A1A, -A1B, -B1B, -B1BD, -C1B, and -D1B. Requirement: 1. Review engine records to determine if:- (a) The engine was last assembled prior to 15 February 1994, or (b) The engine is a first-run engine, or a remanufactured engine from Textron Lycoming, or (c) It can be positively established that, for engines assembled on or after 15 February 1994, the engine contains only connecting rod bolts: (i) that were purchased from Superior Air Parts prior to 15 February 1994 or after 20 December 1994, or (ii) that were purchased directly from Textron Lycoming, or Aircraft Technologies, Inc., or (iii) that have not been replaced since 14 February 1994. For engines that meet the criteria specified in Requirement 1a, 1b, or 1c, no further action is required. Ensure an appropriate statement is entered into the engine log book. 2. For engines that do not meet the criteria specified in Requirement 1, remove cylinders as required and visually inspect each connecting rod bolt to determine if the bolt head is clearly identified with: (a) raised letters "SPS", "S", "C", or "FC", identifying them as Textron Lycoming parts, or (b) SL75060 etched on the head, identifying them as satisfactory PMA parts manufactured by Superior Air Parts, Inc., or (c) AL75060 forged into the head, identifying them as PMA parts manufactured by Aircraft Technologies, Inc. If the connecting rod bolts can be positively identified as satisfying the criteria specified in Requirement 2 no further action is required. Ensure an appropriate statement is entered into the engine log book. 3. If the connecting rod bolts cannot be positively identified as specified in Requirements 1 or 2 of this Directive, remove unapproved connecting rod bolts and replace with serviceable parts. Note 1: FAA Priority Letter Airworthiness Directive 95-07-1 also refers. Note 2: Further information is contained in Superior Air Parts Service Bulletin No. 95-002, dated 3 March 1995, which may be obtained by contacting the local Superior Air Parts representative on (07) 274 4288. Compliance: Effective 31 March 1995, prior to further flight. Background: The FAA has advised that a substantial number of connecting rod bolts have been shipped. At least two engine failures have occurred due to fracture of these bolts. Laboratory examination of these unapproved bolts has determined that the bolts do not meet material or design specifications. The nature of the discrepancies is such that failure is unpredictable and it is impossible to determine analytically how long the bolts may remain intact.