Service Information Letters – Piston

Service Information Letter (SIL) is used to transmit information, recommendations, and general service instructions to the aircraft owner/operator and maintenance personnel.

The information provided in the SILs will be incorporated into the maintenance manual as needed at a later date.

PISTON SERVICE INFORMATION LETTER INDEX

    1. SIL0001 – Engine Crankcase Vent (02/29/1968)
    2. SIL0002 – Fuel Line Chaffing (02/29/1968)
    3. SIL0003 – TR Taper Pins (CXL 10/06/2000)
    4. SIL0004 – Damper Attachment Bolts (CXL 09/11/2000)
    5. SIL0005 – Exhaust Stack (02/10/1969)
    6. SIL 0006  – Damper Rod End (CXL 10/12/2017)
    7. SIL0007 – Cabin Door Handle (02/12/1969)
    8. SIL0008 – Component Service Life (CXL 09/11/2000)
    9. SIL0009 – Belt Idler Shaft (06/04/1969)
    10. SIL0010 – Actuator Arm (CXL 10/06/2000)
    11. SIL0011 – Belt Tension (CXL 09/11/2000)
    12. SIL0012 – Collective, Friction Lock handle (09/19/1969)
    13. SIL0013 – Inlet Air Ducting (09/25/1969)
    14. SIL0014A – Jack Strut Bearing (05/11/1973)
    15. SIL0015 – Pressure and Vent Lines (12/19/1969)
    16. SIL0016-R1 – Alternator Cooling Fan (10/06/2000)
    17. SIL0017 – TR Teetering Hinge Bearings (04/14/1970)
    18. SIL0018 – Stabilizer Attachment Tube (05/05/1970)
    19. SIL0019 – TRGB Housing (11/13/1970)
    20. SIL0020 – Electrical Distribution (02/18/1971)
    21. SIL0021 – Inlet Air Ducting (04/13/1971)
    22. SIL0022 – Engine Instruments (04/30/1971)
    23. SIL0023 – Service Letter Survey (CXL 10/06/2000)
    24. SIL0024 – MR Blade Protection (09/24/1971)
    25. SIL0025 – Swashplate, Rod End (06/26/1972)
    26. SIL0026 – Damper Rod End (05/18/1972)
    27. SIL0027A – Over-Center Mount Pad (04/30/1974)
    28. SIL0028 – Belt Engagement (CXL 10/06/2000)
    29. SIL0029 – MRGB, Oil Filler Cap (CXL 10/06/2000)
    30. SIL0030 – Collective Control, Pilot (10/10/1972)
    31. SIL0031 – Collective Friction Lock (05/31/1973)
    32. SIL0032 – Main Rotor Control Field Phasing (06/04/1973)
    33. SIL0033 – Damper Bleeding Procedure (07/25/1973)
    34. SIL0034 – Abnormal Airframe Vibration (09/20/1973)
    35. SIL0035 – Field Installation TR Blades (12/17/1973)
    36. SIL0036 – Oil Sump (02/04/1974)
    37. SIL0037A – Spindle Nylatron Sleeve (10/01/1983)
    38. SIL0038 – Lubrication, Upper Mast Seal (03/14/1974)
    39. SIL0039 – Setting Autorotation RPM (05/22/1974)
    40. SIL0040 – Certification Eligibility, U.K. (04/26/2017)
    41. SIL0041 – Pulley Alignment, Idler Tracking (CXL 10/06/2000)
    42. SIL0042 – Ground Handling Wheel Procedure (01/17/1975)
    43. SIL0043 – Push-Pull Control Rods (02/20/1975)
    44. SIL0044 – Certification Eligibility, West Germany (CXL 04/26/2017)
    45. SIL0045 – Blade Grip and Spindle (08/11/1975)
    46. SIL0046 – Damper Modification (03/19/1976)
    47. SIL0047 – Service Communications (03/11/1976)
    48. SIL0048 – Cooling Fan Shroud (03/30/1976)
    49. SIL0049 – C Model Factory Conversions (CXL 06/14/1976)
    50. SIL0050 – Rotor Tachometer (CXL 09/05/2018)
    51. SIL0051 – Teeter Bearing (01/27/1977)
    52. SIL0052 – TR Spindle, Narrow Chord (01/27/1977)
    53. SIL0053 – Low Rotor RPM Warning Unit (CXL 10/18/2023)
    54. SIL0054R1 – Induction System Hose Clamps (04/07/2017)
    55. SIL0055 – Main Rotor Damper Fatigue Life (CXL 10/18/2023)
    56. SIL0056 – TR Input Shaft Nut Torque (01/27/1977)
    57. SIL0057 – MRGB Retention Bolts (01/27/1977)
    58. SIL0058 – Fatigue Retirement Lives (CXL 10/18/2023)
    59. SIL0059 – Sealed Bearings (02/15/1977)
    60. SIL0060 – TR Spindle and Teeter Stop (03/10/1977)
    61. SIL0061 – Weight and Balance Fulcrum (04/25/1977)
    62. SIL0062 – Fuel Line Insulation (06/22/1977)
    63. SIL0063 – Turbocharger Oil Inlet Adapter (05/27/1977)
    64. SIL0064 – Idler Stabilizer (06/01/1977)
    65. SIL0065 – Certification Eligibility, U.K. (CXL 04/26/2017)
    66. SIL0066  – Certification  Eligibility, U.K. (CXL 04/26/2017)
    67. SIL0067 – Delivered Configuration, Australia (07/27/1977)
    68. SIL0068 – Oleo Boot (08/23/1977)
    69. SIL0069 – Engine Troubleshooting (10/07/1977)
    70. SIL0070 – Certification Eligibility, U.K. (CXL 04/26/2017)
    71. SIL0071 – (CXL 11/21/2023)
    72. SIL0072 – Certification Eligibility, Germany (05/01/1978)
    73. SIL0073A – MR Retention, O-Ring (05/24/1979)
    74. SIL0074R3  – Drive Belt inspection (11/21/2023) 
    75. SIL0075A – MR Blade Damper (11/20/1980)
    76. SIL0076 – (CXL 11/21/2023)
    77. SIL0077 – MR XMSN, Nut Torque (12/12/1978)
    78. SIL0078 – Fire Wall (12/13/1978)
    79. SIL0079A – Over-Running Clutch (02/14/1980)
    80. SIL0080A – Clutch Control, Belt Tension (08/04/1982)
    81. SIL0081 – Turbocharger, Oil Leakage (12/12/1978)
    82. SIL0082 – Oil Lines (12/13/1978)
    83. SIL0083 – Static Vent System (12/14/1978)
    84. SIL0084 – Pinion Shaft (12/19/1978)
    85. SIL0085 – XMSN Overhaul Interval (12/19/1978)
    86. SIL0086 – TR Rigging Tool (03/05/1979)
    87. SIL0087 – TR Blade Bearing (03/06/1979)
    88. SIL0088R2 – Blade Strike (11/13/2019)
    89. SIL0089 – MR Blade Tape (01/22/1979)
    90. SIL0090 – Fuel Nozzle Air Vent (05/23/1979)
    91. SIL0091A – Engine Starting System (09/26/1980)
    92. SIL0092 – Monitoring EGT System (02/14/1980)
    93. SIL0093 – Starter Ring Gear (02/13/1980)
    94. SIL0094 – Preflight Control System Check (02/25/1980)
    95. SIL0095 – Blades, Corrosion (07/17/1980)
    96. SIL0096 – Fuel Lines, Inspection (07/17/1980)
    97. SIL0097 – (CXL 11/21/2023)
    98. SIL0098 – Turbocharger Gasket (08/06/1980)
    99. SIL0099 – Corrosion Control (08/06/1980)
    100. SIL0100 – MR Flapping Bearing (08/06/1980)
    101. SIL0101 – Position and Strobe Light (08/18/1980)
    102. SIL0102 – TR Teeter Bearing (09/26/1980)
    103. SIL0103 – Overrunning Clutch (11/13/1980)
    104. SIL0104 – TR Blade Tape (CXL 08/14/2019)
    105. SIL0105 – Mageto Retard Timing (11/13/1980)
    106. SIL0106 – Mixture Control (11/13/1980)
    107. SIL0107 – Solar Shield (CXL 04/02/2019)
    108. SIL0108 – Lower Jack Strut (03/17/1981)
    109. SIL0109 – MR and TR Slinger Rings  (03/10/1981)
    110. SIL0110B – Swashplate (03/18/1993)
    111. SIL0111 – Engine Starting (03/11/1981)
    112. SIL0112R1 – MRGB Pinion Drive Key (03/14/2018)
    113. SIL0113 – Landing Light (04/23/1981)
    114. SIL0114 – Safety Equipment (04/28/1981)
    115. SIL0115 – MR Blade Damper (03/09/1981)
    116. SIL0116R8 – Service Life Limits (11/13/2019)
    117. SIL0117 – Auxiliary Oil Cooler (08/26/1981)
    118. SIL0118 – Engine Oil (08/26/1981)
    119. SIL0119 – Magneto Timing (12/02/1981)
    120. SIL0120 – Teeter Bearing (12/02/1981)
    121. SIL0121 – Rotor System Tracking (12/02/1981)
    122. SIL0122 – Starter (04/14/1982)
    123. SIL0123 – Oil Cooler Access (04/14/1982)
    124. SIL0124 – Fuel System (04/14/1982)
    125. SIL0125 – Overboost Warning (07/27/1982)
    126. SIL0126 – Flapping Bearing (07/27/1982)
    127. SIL0127A – MR and TR Blade (12/15/1987)
    128. SIL0128 – (CXL 11/21/2023)
    129. SIL0129 – MR & TR Blade Maintenance and Repair (11/12/1982)
    130. SIL0130 – Eligibility, Gross Weight (10/01/1984)
    131. SIL0131 – Engine Operation (10/01/1984)
    132. SIL0132 – TRDS Flex Couplings (CXL 03/06/2000)
    133. SIL0133 – TR Bearings (06/08/1987)
    134. SIL0134 – Certification Eligibility, U.K. (CXL 04/26/2017)
    135. SIL0135 – Certification Eligibility (CXL 04/26/2017)
    136. SIL0136 – Greases Almagard & Almaplex (10/18/1989)
    137. SIL0137 – Lubrication, Fuels (CXL 09/25/2012)
    138. SIL0138 – PInion Nut, Jack Strut Bearing (09/11/1995)
    139. SIL0139R1 – Rotor Tachometer (10/14/2008)
    140. SIL0140 – Seat Belts (09/11/1995)
    141. SIL0141 – TR Teeter Bearing (09/11/1995)
    142. SIL0142R1 – TR Bumper (02/15/2002)
    143. SIL0143 – Trim Motor Operation, 24 V (05/28/1997)
    144. SIL0144 – Chip Indications (10/03/1997)
    145. SIL0145 – Tracking (10/03/1997)
    146. SIL0146 – MR Control Rod (10/03/1997)
    147. SIL0147R1 – Flapping Bearing (05/29/2015)
    148. SIL0148 – Low Rotor Speed Warning (03/31/1999)
    149. SIL0149 – Lamiflex Bearing (05/03/1999)
    150. SIL0150R1 – Lower Swashplate (03/06/2000)
    151. SIL0151 – Low Rotor, Tone Generator (03/06/2000)
    152. SIL0152 – Belt Tension, Idler Pulley (05/31/2001)
    153. SIL0153 – TR Configuration (02/15/2002)
    154. SIL0154 – Starter Circuit Wiring (09/05/2002)
    155. SIL0155R1 – Drive Belt (09/10/2003)
    156. SIL0156 – MR Push-Pull Rod (12/09/2003)
    157. SIL0157 – MR Damper Valve (01/31/2005)
    158. SIL0158 – TR Pitch Change Link (CXL 05/12/2015)
    159. SIL0159 – Left Side TR Installation (01/31/2005)
    160. SIL0160 – MR Control Rods, Swashplate (10/30/2006)
    161. SIL0161 – MR Damper Oil (05/04/2007)
    162. SIL0162R1 – Tail Rotor Thrust Bearings (11/21/2023)
    163. SIL0163R1 – Turbocharger Adapter Assembly (04/02/2019)
    164. SIL0164 – Cyclic Trim (07/24/2007)
    165. SIL0165R4 – TR Pitch Link (11/10/2017)
    166. SIL0166 – MRGB Bolts, Torque (05/21/2008)
    167. SIL0167R1 – Sliding Window (01/05/2010)
    168. SIL0168 – Rotor System Bearings, Grease (01/20/2009)
    169. SIL0169 – MR Blade Corrosion Maps (04/28/2009)
    170. SIL0170 – Corrosion Prevention (03/22/2010)
    171. SIL0171 – Fuel Filter Servicing (03/26/2012)
    172. SIL0172 – Blade Tape Repair (01/20/2011)
    173. SIL0173 – Pylon Structure (09/02/2010)
    174. SIL0174 – Blade Interchangeability (01/20/2011)
    175. SIL0175 R1 – Turbocharger Adapter (12/12/2023)
    176. SIL0176 – ECD016  & ECD018 Bearings (07/11/2011)
    177. SIL0177 – MR Tracking (08/19/2011)
    178. SIL0178 – Upper Swashplate (04/15/2014)
    179. SIL0179R1 – Copilot Flight Controls (12/20/2017)
    180. SIL0180 – Hi-Lo RPM Switch (11/30/2012)
    181. SIL0181 – Production Certificate (04/15/2014)
    182. SIL0182R1 – Fuel Management (11/07/2017)
    183. SIL0183 – Collective Stick Socket (08/19/2015)
    184. SIL0184R3 – Collective Trim Adjustment Rod Assembly (05/16/2013)
    185. SIL0185 – EDM CHT Probe Installation (05/19/2016)
    186. SIL0186 – Wastegate Linkage and Throttle Cable Installation 03/30/2016)
    187. SIL0187 – Universal Block (11/09/2016)
    188. SIL0188 – Oil Pressure Gauge Troubleshooting (12/01/2016)
    189. SIL0189 – Magneto Retard Terminal P-Lead Insulator (02/04/2019)
    190. SIL0190 – Cabin Door Removal (04/02/2019)
    191. SIL0191 – Lamiflex Bearing Discontinuation (08/14/2019)
    192. SIL0192 – Tail Rotor Cable Assembly (12/09/2019)
    193. SIL 0193R1 – TRGB Oil Check and Servicing (05/09/2023)