{"id":113,"date":"2012-12-21T15:49:33","date_gmt":"2012-12-21T15:49:33","guid":{"rendered":"http:\/\/hartzellprop.com\/\/?page_id=113"},"modified":"2026-05-13T06:10:59","modified_gmt":"2026-05-13T11:10:59","slug":"service-letters","status":"publish","type":"page","link":"https:\/\/hartzellprop.com\/services\/product-support-library\/service-documents\/service-letters\/","title":{"rendered":"Service Letters"},"content":{"rendered":"

This is a collection of Hartzell Service Letters.\u00a0All active Hartzell Service Bulletins, Service Letters, Service Instructions, and Service Advisories are available for purchase as part of the Hartzell Technical Documents Library on CD Rom. Contact New Parts Sales at 001 (937) 778-4201 (option 1) or e-mail newpartssales@hartzellprop.com<\/a><\/p>\n

NOTE: The following Service\u00a0Letters are arranged in\u00a0descending numerical order.<\/strong><\/p>\n

To open PDF documents, the free Adobe Reader is required. Click here to download and install it.<\/a><\/p>\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n
Title<\/th>\nDate<\/th>\nRevision<\/th>\nDescription<\/th>\n<\/tr>\n
Service Letter Index<\/a><\/td>\nMay 13, 2026<\/td>\n<\/td>\nService Letter Index<\/td>\n<\/tr>\n
HC-SL-61-377<\/a><\/td>\nJun. 11, 2025<\/td>\n<\/td>\nCounterweight clamp corrosion<\/td>\n<\/tr>\n
HC-SL-61-376<\/a><\/td>\nMay 13, 2026<\/td>\n1<\/td>\nTE432 Torque Wrench Adapter Modification and Alternate Mounting Washer Introduction<\/td>\n<\/tr>\n
HC-SL-61-375<\/a><\/td>\nSep. 18, 2024<\/td>\n2<\/td>\nTanis\/Hartzell Part Number Cross-Reference<\/td>\n<\/tr>\n
HC-SL-61-374<\/a><\/td>\nMar. 08, 2023<\/td>\n<\/td>\nOnline Product Registration<\/td>\n<\/tr>\n
HC-SL-61-373<\/a><\/td>\nDec. 07, 2022<\/td>\n<\/td>\nSplit Bearing Race Adhesive<\/td>\n<\/tr>\n
HC-SL-61-372<\/a><\/td>\nDec. 07, 2022<\/td>\n<\/td>\nBlade Decals<\/td>\n<\/tr>\n
HC-SL-61-371<\/a><\/td>\nAug. 05, 2021<\/td>\n<\/td>\nAlternate O-ring (p\/n C-3317-AR-157)<\/td>\n<\/tr>\n
HC-SL-61-370<\/a><\/td>\nJul. 07, 2021<\/td>\n<\/td>\nBeta System Cleaning (agricultural\/firefighting installations)<\/td>\n<\/tr>\n
HC-SL-30-369<\/a><\/td>\nNov. 03, 2021<\/td>\n<\/td>\nErosion Tape on Blades w\/De-ice Boots<\/td>\n<\/tr>\n
HC-SL-61-368<\/a><\/td>\nNov. 18, 2021<\/td>\n<\/td>\nIntroduction of redesigned propeller hubs<\/td>\n<\/tr>\n
HC-SL-61-367<\/a><\/td>\nDec. 17, 2020<\/td>\n1<\/td>\n107995 Counterweight Mounting Bolt<\/td>\n<\/tr>\n
HC-SL-61-366<\/a><\/td>\nJan. 06, 2020<\/td>\n<\/td>\nPropeller – NYCO GN3058 Grease<\/td>\n<\/tr>\n
HC-SL-61-364<\/a><\/td>\nApr. 03, 2020<\/td>\n<\/td>\nPropeller – Corrosion Inhibitor on Counterweights<\/td>\n<\/tr>\n
HC-SL-61-362<\/a><\/td>\nSep 05, 2018<\/td>\n<\/td>\nPropeller – A-1851-T Blade Retention Bearings<\/td>\n<\/tr>\n
HC-SL-61-361<\/a><\/td>\nApr 27, 2017<\/td>\n<\/td>\nPropeller – Unfeathering Tool TE316<\/td>\n<\/tr>\n
HC-SL-61-360<\/a><\/td>\nAug 01, 2018<\/td>\n1<\/td>\nBlade – Damage Evaluation for NC10245( ) Blades Installed on (but not limited to) Pilatus PC-12 Aircraft<\/td>\n<\/tr>\n
HC-SL-61-359<\/a><\/td>\nOct 02, 2017<\/td>\n<\/td>\nPolane\u00ae Paint (Silver) CM163<\/td>\n<\/tr>\n
HC-SL-61-358<\/a><\/td>\nDec 01, 2016<\/td>\n<\/td>\nPropeller – Beta System Puller TE100<\/td>\n<\/tr>\n
HC-SL-61-354<\/a><\/td>\nAug 1, 2016<\/td>\n<\/td>\nPropeller – Lubrication Fittings<\/td>\n<\/tr>\n
HC-SL-61-353<\/a><\/td>\nNov 11, 2015<\/td>\n<\/td>\nPropeller – AeroShell 5 Grease<\/td>\n<\/tr>\n
HC-SL-61-346<\/a><\/td>\nOct 1, 2015<\/td>\n<\/td>\nSpinner – Bulkhead Modification<\/td>\n<\/tr>\n
HC-SL-61-343<\/a><\/td>\nApr 1, 2014<\/td>\n<\/td>\nProduct Category – Lubrication Procedure<\/td>\n<\/tr>\n
HC-SL-30-335<\/a><\/td>\nNov. 01, 2019<\/td>\n3<\/td>\nRestrainer Strap Installation<\/td>\n<\/tr>\n
HC-SL-61-324<\/a><\/td>\nOct 21, 2011<\/td>\n<\/td>\nBlade – Aluminum Blade Field Repair<\/td>\n<\/tr>\n
HC-SL-30-308<\/a><\/td>\nDec. 07, 2022<\/td>\n1<\/td>\nHartzell PMA De-ice Components<\/td>\n<\/tr>\n
HC-SL-30-304<\/a><\/td>\nDec 22, 2015<\/td>\n3<\/td>\nPropeller modification to anti-ice configuration<\/td>\n<\/tr>\n
HC-SL-30-295<\/a><\/td>\nNov 06, 2013<\/td>\n3<\/td>\nNew PC-12 De-Ice boot<\/td>\n<\/tr>\n
HC-SL-61-294<\/td>\nMay 15, 2012<\/td>\n1<\/td>\nfield Maintenance of Hartzell Composite Blades – NOTE: This Service Document has\u00a0been replaced by Hartzell Manual 170<\/a><\/td>\n<\/tr>\n
HC-SL-30-279<\/a><\/td>\nMar 06, 2013<\/td>\n8<\/td>\nIntroduction of De-ice boot 6-digit Hartzell De-Ice boots replacing a “4H” De-ice boot<\/td>\n<\/tr>\n
HC-SL-61-277<\/a><\/td>\nSep 16, 2020<\/td>\n6<\/td>\nGovernor installation instructions<\/td>\n<\/tr>\n
HC-SL-61-265<\/a><\/td>\nOct 09, 2009<\/td>\n2<\/td>\nIntroduction of smooth forged hubs for 3-blade compact propellers<\/td>\n<\/tr>\n
HC-SL-30-260<\/a><\/td>\nSep. 01, 2022<\/td>\n23<\/td>\nIntroduction of Hartzell airframe mounted Ice protection components, De-ice boots and Anti-ice feed shoes<\/td>\n<\/tr>\n
HC-SL-30-259<\/a><\/td>\nMar. 09, 2022<\/td>\n15<\/td>\nIntroduction of Hartzell De-Ice components(wire harness, slip rings, and De-ice boots)<\/td>\n<\/tr>\n
HC-SL-61-254<\/a><\/td>\nMar. 09, 2022<\/td>\n1<\/td>\nPropeller – Propeller Operating Restrictions<\/td>\n<\/tr>\n
HC-SL-30-246<\/a><\/td>\nJun 02, 2005<\/td>\n<\/td>\nDe-Ice – Spare Parts Release<\/td>\n<\/tr>\n
HC-SL-61-241<\/a><\/td>\nFeb 02, 2015<\/td>\n3<\/td>\nIntroduction of B-7726 blade seal for lightweight turbine propellers<\/td>\n<\/tr>\n
HC-SL-61-231<\/a><\/td>\nApr 01, 2004<\/td>\n<\/td>\nPropellers – Use of Propeller Jack<\/td>\n<\/tr>\n
HC-SL-61-225<\/a><\/td>\nDec 18, 2003<\/td>\n1<\/td>\nSpinners – Spinner Dome and Bulkhead Assembly Manufacturing Process Improvements<\/td>\n<\/tr>\n
HC-SL-61-187<\/a><\/td>\nMar. 09, 2022<\/td>\n5<\/td>\nAlternate lubrication fittings for aluminum hub propellers<\/td>\n<\/tr>\n
HC-SL-61-171<\/a><\/td>\nMay 28, 1996<\/td>\n<\/td>\nSpinner dome and bulkhead interchangeability<\/td>\n<\/tr>\n
HC-SL-61-165<\/a><\/td>\nDec 07, 1995<\/td>\n<\/td>\nAll propellers – Warning to evaluate unusual grease leaks or vibration<\/td>\n<\/tr>\n
HC-SL-61-61Y<\/a><\/td>\nMay 13, 2026<\/td>\n18<\/td>\nOverhaul periods and Service life limits for Hartzell Propeller Inc. Aviation Components – Propellers, Governors. Accumulators, and Propeller Damper Assemblies (Ref. AD 77-12-06)<\/td>\n<\/tr>\n
HC-SL-61-48A<\/a><\/td>\nDec. 07, 2022<\/td>\n3<\/td>\nPropeller – Diaphram Inspection<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n","protected":false},"excerpt":{"rendered":"

This is a collection of Hartzell Service Letters.\u00a0All active Hartzell Service Bulletins, Service Letters, Service Instructions, and Service Advisories are available for purchase as part of the Hartzell Technical Documents Library on CD Rom. Contact New Parts Sales at 001 (937) 778-4201 (option 1) or e-mail newpartssales@hartzellprop.com NOTE: The following Service\u00a0Letters are arranged in\u00a0descending numerical […]<\/p>\n","protected":false},"author":6,"featured_media":2589,"parent":85,"menu_order":0,"comment_status":"open","ping_status":"open","template":"","meta":{"_acf_changed":false,"inline_featured_image":false,"footnotes":""},"class_list":["post-113","page","type-page","status-publish","has-post-thumbnail","hentry"],"acf":[],"yoast_head":"\nService Letters - Hartzell Propeller Inc.<\/title>\n<meta name=\"description\" content=\"All active Hartzell Service Letters are available for purchase as part of the Hartzell Technical Documents Library on CD Rom.\" \/>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/hartzellprop.com\/services\/product-support-library\/service-documents\/service-letters\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Service Letters - 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