74-08-01: Autopilot Servo Actuators

74-08-01 AIRCRAFT RADIO CORPORATION: Amendment 39-1808. Applies to Aircraft Radio Corporation autopilot servo actuators PA-500A, PA-520A, or PA-520B used in 300 and 400 series Cessna autopilots and 300, 400 and 800 series IFCS. Refer to attached list of those Cessna Model airplanes which may have had these actuators installed at the factory or in the field. Subject actuators may have been installed or used as replacement parts in other aircraft. \n\n\tCompliance: Required as indicated, unless already accomplished. \n\n\tTo prevent possible jamming of the autopilot actuator due to an internal screw becoming loose and jamming against the internal surface of the actuator case body, accomplish the following: \n\n\tA)\tFor all aircraft with 300 hours' or less time in service since autopilot installation, within 25 hours' time in service after the effective date of this AD, inspect the autopilot actuators and take action in accordance with Cessna Avionics Service Letter AV74-3 and ARC Service Bulletin No. 171 or later FAA-approved revisions. \n\n\tB)\tFor all aircraft with more than 300 hours' time in service since autopilot installation, during the next routine, annual, or 100-hour inspection, whichever comes first, inspect the autopilot actuators and take action in accordance with Cessna Avionics Service Letter AV74-3, and ARC Service Bulletin No. 171 or later FAA-approved revisions. \n\n\tC)\tAny alternate method of compliance with this AD must be referred to and approved by the Chief, Engineering and Manufacturing Branch, FAA, Central Region. \n\n\tThis amendment becomes effective April 9, 1974. \n\nATTACHMENT - CESSNA AIRCRAFT MODEL AND SERIAL EFFECTIVITY \n\nMODELS 172L and M - 17259287 thru 63027 \n\nMODEL F172K, L, and M - F1720780 thru 1004, 1006 thru 1009, 1012, 1013, 1015 thru 1033, 1035, 1037 thru 1039, 1041 thru 1044, 1046, 1047, 1049, 1050, 1053, 1054, 1056, 1057, 1060, 1062, 1066, 1068, 1070, 1072, 1076, 1079, 1086, 1090, 1091, 1094 thru 1096, 1099, 1102, 1107, 1115 \n\nMODEL FR172H - FR1720240 thru 0427, 0429, 0431, 0432, 0434, 0437, 0438, 0440 thru 0445, 0447, 0449, 0450 thru 0452, 0454 thru 0457, 0462 \n\nMODEL 177B - 17701576 thru 02077 \n\nMODEL 177RG - 177RG0001 thru 0442, 0444 thru 0502 \n\nMODEL F177RG - F177RG0001 thru 0095 \n\nMODEL 180H & J - 18052170 thru 52429 \n\nMODEL 182N & P - 18260460 thru 62493, 62495 thru 62764, 62766 thru 62813, 62815 thru 62840, 62842 thru 62853, 62855 thru 62914 \n\nMODEL 185 E and F - 18501815 thru 02376 \n\nMODEL P206E - P20600626 thru 00647 \n\nMODEL U206 E and F - U20601447 thru 02265, 02267 thru 02290, 02292 thru 02303, 02305 thru 02309, 02311 thru 02333, 02337 thru 02339 \n\nMODEL 207 - 20700149 thru 00243 \n\nMODEL 210K and L - 21059200 200 thru 60089, 60091 thru 60104, 60106 thru 60155, 60157 thru 60163, 60165 thru 60167, 60169 thru 60171, 60174 thru 60176, 60178 thru 60180, 60182 thru 60184, 60186, 60187, 60189 thru 60193, 60196, 60198, 60201, 60202, 60204 thru 60206, 60208, 60212, 60213, 60215, 60216, 60217, 60227, 60228, 60230, 60232, 60233 thru 60236, 60238 thru 60240 \n\nMODEL 310Q - 310Q0001 thru 1027, 1034, 1037 \n\nMODEL 337E and F - 33701290 thru 01532, 01534 thru 01567, 01569 thru 01572, 01575 thru 01578, 01579 thru 01581, 01583 thru 01585, 01587 thru 01589, 01592 \n\nMODEL F337G - F3370020 thru 0063 \n\nMODEL T337G - P3370001 thru 0045, 0047 thru 0065, 0067 thru 0132, 0134 thru 0139, 0142 thru 0147, 0150, 0154, 0155, 0156, 0158, 0159 \n\nMODEL FT337G - FP3370001, 0003, 0005, 0008 \n\nMODEL 340 - 3400001 thru 0322 \n\nMODEL 401B - 401B0001 thru 0221 \n\nMODEL 402B - 402B0001 thru 0445, 0447 thru 0508, 0510 thru 0525, 0527 thru 0529, 0531 thru 0547, 0549, 0550, 0552 thru 0558, 0560 thru 0567 \n\nMODEL 414 - 4140001 thru 0498 \n\nMODEL 421B - 421B0001 thru 0559, 0561 thru 0573, 0576 thru 0579