73-23-01: Piston Pin Assembly
FAA order 73-23-01 is an airworthiness directive in force since January 13, 1977. The FAA's subject line: Piston Pin Assembly. It names the Lycoming GO-480-G1D6, Lycoming HIO-360-A1A, Lycoming HIO-360-B1A, Lycoming HIO-360-B1B, Lycoming HIO-360-C1A, Lycoming HIO-360-C1B, Lycoming HIO-360-D1A, Lycoming IGO-540-A1C, Lycoming IGO-540-B1A, Lycoming IGSO-480-A1E6, Lycoming IGSO-540-B1A, Lycoming IO-320-A1A, Lycoming IO-320-B1A, Lycoming IO-320-B1C, Lycoming IO-320-B2A, Lycoming IO-320-C1A, Lycoming IO-320-D1A, Lycoming IO-320-D1B, Lycoming IO-320-E1A, Lycoming IO-320-E2A, Lycoming IO-320-E2B, Lycoming IO-320 series, Lycoming IO-360-A1A, Lycoming IO-360-A1B, Lycoming IO-360-A1B6, Lycoming IO-360-A1B6D, Lycoming IO-360-A1D, Lycoming IO-360-A1D6, Lycoming IO-360-A2B, Lycoming IO-360-B1A, Lycoming IO-360-B1B, Lycoming IO-360-B1C, Lycoming IO-360-B1D, Lycoming IO-360-B1E, Lycoming IO-360-B1F, Lycoming IO-360-B1F6, Lycoming IO-360-B2E, Lycoming IO-360-B2F, Lycoming IO-360-B4A, Lycoming IO-360-C1A, Lycoming IO-360-C1C, Lycoming IO-360-C1D6, Lycoming IO-360-C1F, Lycoming IO-360-D1A, Lycoming IO-360-E1A, Lycoming IO-360-F1A, Lycoming IO-360 series, Lycoming IO-540-A1A5, Lycoming IO-540-B1A5, Lycoming IO-540-C4B5, Lycoming IO-540-D4A5, Lycoming IO-540-E1A5, Lycoming IO-540-E1B5, Lycoming IO-540-G1D5, Lycoming IO-540-J4A5, Lycoming IO-540-K1A5, Lycoming IO-540-K1B5, Lycoming IO-540-K1C5, Lycoming IO-540-K1E5, Lycoming IO-540 series, Lycoming IO-720, Lycoming IO-720-A1B, Lycoming LIO-360-C1E6, Lycoming O-320-A1A, Lycoming O-320-A1B, Lycoming O-320-A2A, Lycoming O-320-A2B, Lycoming O-320-A2C, Lycoming O-320-A2D, Lycoming O-320-A3A, Lycoming O-320-A3B, Lycoming O-320-A3C, Lycoming O-320-B1A, Lycoming O-320-B1B, Lycoming O-320-B2A, Lycoming O-320-B2B, Lycoming O-320-B2C, Lycoming O-320-B3B, Lycoming O-320-C1A, Lycoming O-320-C2A, Lycoming O-320-C3B, Lycoming O-320-D1A, Lycoming O-320-D1F, Lycoming O-320-D2A, Lycoming O-320-D2B, Lycoming O-320-D2C, Lycoming O-320-E1A, Lycoming O-320-E1F, Lycoming O-320-E2A, Lycoming O-320-E2B, Lycoming O-320-E2C, Lycoming O-320-E2D, Lycoming O-320-E2G, Lycoming O-320-E3D, Lycoming O-320-E3H, Lycoming O-320 series, Lycoming O-360-A1A, Lycoming O-360-A1D, Lycoming O-360-A1F, Lycoming O-360-A1F6, Lycoming O-360-A1F6D, Lycoming O-360-A1G, Lycoming O-360-A1G6, Lycoming O-360-A1H, Lycoming O-360-A1LD, Lycoming O-360-A2A, Lycoming O-360-A2D, Lycoming O-360-A2F, Lycoming O-360-A2G, Lycoming O-360-A3A, Lycoming O-360-A4A, Lycoming O-360-A4G, Lycoming O-360-B1A, Lycoming O-360-B1B, Lycoming O-360-B2A, Lycoming O-360-C1A, Lycoming O-360-C2A, Lycoming O-360-C2C, Lycoming O-360-C2D, Lycoming O-360-D1A, Lycoming O-360-D2A, Lycoming O-360 series, Lycoming O-540-A1C5, Lycoming O-540-A1D5, Lycoming O-540-B1A5, Lycoming O-540-B2B5, Lycoming O-540-B2C5, Lycoming O-540-B4B5, Lycoming O-540-E4A5, Lycoming O-540-E4B5, Lycoming O-540-E4C5, Lycoming O-540-G1A5, Lycoming TIGO-541-E1A, Lycoming TIGO-541 series, Lycoming TIO-360-C1A6D, Lycoming TIO-360 series, Lycoming TIO-540-A2B, Lycoming TIO-540-A2C, Lycoming TIO-540-C1A, Lycoming TIO-540-J2BD, Lycoming TIO-541-A1A, Lycoming TIO-541-E1C4, Lycoming TIO-541 series, Lycoming VO-540-B1B3, Lycoming VO-540-C2A, Lycoming VO-540 series engines: about 50,372 aircraft on the U.S. register today across them, though an order usually covers particular versions or serial numbers rather than every one. System: engine.
What it applies to as the FAA lists it
- Kind of product
- Engine
- Makes
- Lycoming Engines; Textron Lycoming, AVCO Corporation
- Models
- AIO-360-A1A, AIO-360-A1B, AIO-360-A2A, AIO-360-A2B, AIO-360-B1B, GO-480-G1D6, HIO-360-A1A, HIO-360-B1A, HIO-360-B1B, HIO-360-C1A, HIO-360-C1B, HIO-360-D1A, IGO-540-A1A, IGO-540-A1B, IGO-540-A1C, IGO-540-B1A, IGO-540-B1B, IGO-540-B1C, IGSO-480-A1E6, IGSO-540-A1A, IGSO-540-A1C, IGSO-540-A1D, IGSO-540-A1E, IGSO-540-A1F, IGSO-540-B1A, IGSO-540-B1C, IO-320-A1A, IO-320-A2A, IO-320-B1A, IO-320-B1B, IO-320-B1C, IO-320-B1D, IO-320-B2A, IO-320-C1A, IO-320-D1A, IO-320-D1B, IO-320-E1A, IO-320-E2A, IO-320-E2B, IO-360-A1A, IO-360-A1B, IO-360-A1B6, IO-360-A1B6D, IO-360-A1C, IO-360-A1D, IO-360-A1D6,...
- Engine series
- Lycoming GO-480-G1D6 7 aircraft
Lycoming HIO-360-A1A 5 aircraft
Lycoming HIO-360-B1A 16 aircraft
Lycoming HIO-360-B1B 2 aircraft
Lycoming HIO-360-C1A 6 aircraft
Lycoming HIO-360-C1B 1 aircraft
Lycoming HIO-360-D1A 41 aircraft
Lycoming IGO-540-A1C 1 aircraft
Lycoming IGO-540-B1A 9 aircraft
Lycoming IGSO-480-A1E6 1 aircraft
Lycoming IGSO-540-B1A 48 aircraft
Lycoming IO-320-A1A 2 aircraft
Lycoming IO-320-B1A 55 aircraft
Lycoming IO-320-B1C 2 aircraft
Lycoming IO-320-B2A 1 aircraft
Lycoming IO-320-C1A 7 aircraft
Lycoming IO-320-D1A 57 aircraft
Lycoming IO-320-D1B 6 aircraft
Lycoming IO-320-E1A 3 aircraft
Lycoming IO-320-E2A 11 aircraft
Lycoming IO-320-E2B 4 aircraft
Lycoming IO-320 series 1,707 aircraft
Lycoming IO-360-A1A 195 aircraft
Lycoming IO-360-A1B 52 aircraft
Lycoming IO-360-A1B6 141 aircraft
Lycoming IO-360-A1B6D 844 aircraft
Lycoming IO-360-A1D 15 aircraft
Lycoming IO-360-A1D6 191 aircraft
Lycoming IO-360-A2B 2 aircraft
Lycoming IO-360-B1A 49 aircraft
Lycoming IO-360-B1B 67 aircraft
Lycoming IO-360-B1C 6 aircraft
Lycoming IO-360-B1D 2 aircraft
Lycoming IO-360-B1E 184 aircraft
Lycoming IO-360-B1F 8 aircraft
Lycoming IO-360-B1F6 3 aircraft
Lycoming IO-360-B2E 3 aircraft
Lycoming IO-360-B2F 1 aircraft
Lycoming IO-360-B4A 969 aircraft
Lycoming IO-360-C1A 7 aircraft
Lycoming IO-360-C1C 45 aircraft
Lycoming IO-360-C1D6 14 aircraft
Lycoming IO-360-C1F 2 aircraft
Lycoming IO-360-D1A 4 aircraft
Lycoming IO-360-E1A 3 aircraft
Lycoming IO-360-F1A 3 aircraft
Lycoming IO-360 series 8,560 aircraft
Lycoming IO-540-A1A5 16 aircraft
Lycoming IO-540-B1A5 4 aircraft
Lycoming IO-540-C4B5 179 aircraft
Lycoming IO-540-D4A5 236 aircraft
Lycoming IO-540-E1A5 4 aircraft
Lycoming IO-540-E1B5 4 aircraft
Lycoming IO-540-G1D5 26 aircraft
Lycoming IO-540-J4A5 9 aircraft
Lycoming IO-540-K1A5 44 aircraft
Lycoming IO-540-K1B5 17 aircraft
Lycoming IO-540-K1C5 1 aircraft
Lycoming IO-540-K1E5 5 aircraft
Lycoming IO-540 series 4,218 aircraft
Lycoming IO-720 119 aircraft
Lycoming IO-720-A1B 8 aircraft
Lycoming LIO-360-C1E6 6 aircraft
Lycoming O-320-A1A 20 aircraft
Lycoming O-320-A1B 2 aircraft
Lycoming O-320-A2A 9 aircraft
Lycoming O-320-A2B 180 aircraft
Lycoming O-320-A2C 1 aircraft
Lycoming O-320-A2D 13 aircraft
Lycoming O-320-A3A 5 aircraft
Lycoming O-320-A3B 12 aircraft
Lycoming O-320-A3C 1 aircraft
Lycoming O-320-B1A 17 aircraft
Lycoming O-320-B1B 3 aircraft
Lycoming O-320-B2A 11 aircraft
Lycoming O-320-B2B 92 aircraft
Lycoming O-320-B2C 55 aircraft
Lycoming O-320-B3B 22 aircraft
Lycoming O-320-C1A 1 aircraft
Lycoming O-320-C2A 2 aircraft
Lycoming O-320-C3B 1 aircraft
Lycoming O-320-D1A 116 aircraft
Lycoming O-320-D1F 7 aircraft
Lycoming O-320-D2A 72 aircraft
Lycoming O-320-D2B 18 aircraft
Lycoming O-320-D2C 1 aircraft
Lycoming O-320-E1A 3 aircraft
Lycoming O-320-E1F 5 aircraft
Lycoming O-320-E2A 98 aircraft
Lycoming O-320-E2B 4 aircraft
Lycoming O-320-E2C 11 aircraft
Lycoming O-320-E2D 257 aircraft
Lycoming O-320-E2G 32 aircraft
Lycoming O-320-E3D 65 aircraft
Lycoming O-320-E3H 2 aircraft
Lycoming O-320 series 27,316 aircraft
Lycoming O-360-A1A 600 aircraft
Lycoming O-360-A1D 1,057 aircraft
Lycoming O-360-A1F 4 aircraft
Lycoming O-360-A1F6 13 aircraft
Lycoming O-360-A1F6D 18 aircraft
Lycoming O-360-A1G 1 aircraft
Lycoming O-360-A1G6 1 aircraft
Lycoming O-360-A1H 8 aircraft
Lycoming O-360-A1LD 1 aircraft
Lycoming O-360-A2A 38 aircraft
Lycoming O-360-A2D 5 aircraft
Lycoming O-360-A2F 13 aircraft
Lycoming O-360-A2G 3 aircraft
Lycoming O-360-A3A 50 aircraft
Lycoming O-360-A4A 63 aircraft
Lycoming O-360-A4G 2 aircraft
Lycoming O-360-B1A 13 aircraft
Lycoming O-360-B1B 2 aircraft
Lycoming O-360-B2A 3 aircraft
Lycoming O-360-C1A 7 aircraft
Lycoming O-360-C2A 19 aircraft
Lycoming O-360-C2C 6 aircraft
Lycoming O-360-C2D 2 aircraft
Lycoming O-360-D1A 6 aircraft
Lycoming O-360-D2A 4 aircraft
Lycoming O-360 series 1,066 aircraft
Lycoming O-540-A1C5 4 aircraft
Lycoming O-540-A1D5 18 aircraft
Lycoming O-540-B1A5 1 aircraft
Lycoming O-540-B2B5 27 aircraft
Lycoming O-540-B2C5 13 aircraft
Lycoming O-540-B4B5 40 aircraft
Lycoming O-540-E4A5 9 aircraft
Lycoming O-540-E4B5 21 aircraft
Lycoming O-540-E4C5 15 aircraft
Lycoming O-540-G1A5 6 aircraft
Lycoming TIGO-541-E1A 1 aircraft
Lycoming TIGO-541 series 37 aircraft
Lycoming TIO-360-C1A6D 3 aircraft
Lycoming TIO-360 series 15 aircraft
Lycoming TIO-540-A2B 4 aircraft
Lycoming TIO-540-A2C 6 aircraft
Lycoming TIO-540-C1A 9 aircraft
Lycoming TIO-540-J2BD 24 aircraft
Lycoming TIO-541-A1A 1 aircraft
Lycoming TIO-541-E1C4 9 aircraft
Lycoming TIO-541 series 273 aircraft
Lycoming VO-540-B1B3 3 aircraft
Lycoming VO-540-C2A 6 aircraft
Lycoming VO-540 series 110 aircraft
Dates and paperwork
- In force since
- January 13, 1977
- Docket
- Unknown
- Status
- Current
- The FAA's document
- Read the order on the FAA's site
The order itself the regulatory text, as published
Show the full text (7,262 characters)
Source: FAA Dynamic Regulatory System, airworthiness directives. The FAA's document is the authority; the register counts are this site's, from the FAA register of October 5, 2026. Connections as data: /graph/directive/73-23-01.json · aircraft systems.
