PIPER TWIN COMANCHE SERVICE MANUAL

Balancing Stabilator, Serial Nos. 30-853. 30-902 to 30-17' 6 incl.. and '30-1718 to 30-1744 incl. . Checking and Balancing Rudder •............................................ Surface Scratches, Abrasion or Ground-in-Dirt . Deep Scratches, Shallow Nicks and Small Holes . Mixing of Epoxy Patching Compound , . Welding Repair Method . Repairing of Cracks . Various Repairs . Repair of Stress Lines . Repair: of Impacted Damage . Control Column Installation . Correct Method of Installing Rod End Bearings . Aileron Control Installation " . Installation of Bellcrank Checking Tool . Installation of Aileron Rigging Tool ' . Stabilator and Stabilator Trim Controls .......................•.............. Stabilator Rigging Tool . Methods of Blocking Trim Cables . Rudder Pedal Installation . Adjustment of Brake Pedal . Rudder and Rudder Trim Controls ' . Clamping Rudder Pedals in Neutral Position . Determining Neutral Rudder Position ' ' . Checking Rudder Travel : . Trim Screw Assembly . Aap Control Installation . Flap Position Sender Unit . Fabricated Aileron Bellcrank Rigging Tool . Fabricated Aileron Rigging Tool . Fabricated Stabilator Rigging Tool . Nose Gear Oleo Strut Assembly . Nose Landing Gear Installation . Clamping Rudder Pedals in Neutral Position ............................•..... Rudder Pedals at Neutral Angle ...•......................................... Rudder Pedals at Neutral Position SI N 39-84 and up . Installation of Plumb Bob Attachment Tool . Installation of Nose Gear Alignment Jig . IFIS IFIS IFI8 IF23 IF23 IF24 IF24 IGI IG3 IG4 IG4 IGI6 IGI9 IG23 IH3 IH3 IH8 IH 12 IH 13 IH20 IH21 IH23 112 113 113 1110 1120 1123 IJ 13 IJ 14 IJ IS 2AI7 2A23 2BI 2B2 282 2B4 2B4 Revised: 10/28/82 lA6 LIST OF ILLUSTRA TlONS (cont.) Figure •Aerofiche Grid ~o. 7-7. 7-S. 7-Sa. 7-Sb. 7-Sc. 7-9. 7-10. 7-11. 7-12. 7-13. 7-14. 7-15. 7-16. 7-17. 7-IS. 7-19. 7-20. 7-21. 7-22. 7-22a. 7-23. 7-24. 7-25. 7-26. 7-268. 7-27. 7-28. 7-29. 7-30. 7-31. 7-32. 8-1. 8-2. 8-3. 8-4, 8-5. 8-6. 8-7. S-8. Nose Gear Door Installation . Main Gear Oleo Strut Assembly . Main Gear Side Brace Link Travel .. ' . Main Gear Side Brace Bearing Tolerance . Main Gear Side Brace Link Tolerance " . Main Landing Gear Installation (left) . Adjustment of Main landing Gear Drag Link . Aligning Main Gear . landing Gear Retraction System ' .. Landing Gear Retraction Transmission Assembly , . Landing Gear Retraction Transmission Installation . Landing Gear Up Limit Switch . Torque Wrench and Adapter Installation . Landing Gear Down Lock Installation . Landing Gear Warning Switch Installation , . Nose Wheel Assembly . Main Wheel Assembly, Serial Nos. 30-2 to 30-S45 incl. . Main Wheel Assembly, Serial Nos. 30-S46 to 30-2000 incl. . Wheel Brake Assembly . Removal and Installation of Anchor Bolt . Removal of Wheel Brake Disc ' . Brake System Installation . Brake Master Cylinder Assembly . Bleeding Brakes ..............................•............................ Brake Cylinder Installation ; .•.............................•................ Fabricated Plumb Bob Tool .....•.•.•...•...••............................. Fabricated Nose Wheel Alignment Jig , . Fabricated Spanner Wrench . Inspection of Rod End Bearings . Main Gear Wear Limits ••......•...••..•••................................. Nose Gear Wear Limits . Engine Cowling and Cowl Aap Rigging . Standard Propeller Installation .....•...... ' . Typical Nicks and Removal Methods . Propeller Governor . Engine Installation . Schematic Diagram of RSA Fuel Injector System , . Fuel Injector ............................•..•.............................. Fuel Air Bleed Nozzle ....................••................................ 2B5 3B9 2B'I4 2BI4 2BI5 2B 19 2B21 2B22 2CI 2C4 2CIO 2CI2 2Cl4 2CI5 2CI6 2CIS 2CI9 2C20 2C22 2C23 2C24 201 203 205 205 209 2010 2011 2012 2014 2016 2023 2El 2E4 2EIO 2E 15 2El9 . 2E21 2E21 • Revised: 10/28/82 IA7 .' LIST OF ILLUSTRATIONS (cont.) Figure Aerofiche Grid ~o. • 8-9. S-IO. S-II. S-12. S-I3. S-14. S-15. S-16. S-17. S-IS. S-1.9. S':'20. S-21. S-22. 8-23. 8-24. 8-25. S-26. 8-27. 8A-I. 8A-2. SA-3. SA-4. SA-5. SA-6. SA-7. SA-8. 8A-9. 8A-IO. SA-II. SA-12. SA-I3. SA-14. 8A-15. 8A-16. 8A-17. SA-18. 8A-19. 8A-20. SA-21. SA-22. 8A-23. 8A-24. 8A-25: Magneto Breaker Points . Contact Spring Inspection ..•............................................... Impulse Coupling . Magneto Timing Marks " . Engine Timing Marks . Remoying Spring From Lead Assembly . Assembly Tool . Using Assembly Tool " . Measuring Lead Assembly Length . Cutting Metallic Braid from End of Lead . Unbraiding Metallic .Shielding . Forming Shielding Around Ferrule . Ferrule Seating Tool . Needle' . Measuring Wire From Top of Ferrule . Installing Grommet Over Lead Assemblies . Lead Assembly Installed in Grommet . Wire Doubled Over For Installation of Eyelet . Removing Frozen Spark Plug . Engine Cowling and Cowl Flap Rigging . Propeller Installation . Typical Nicks and Removal Methods . Propeller Governor . Engine Installation . Schematic Diagram of Turbocharged System . Schematic Diagram of RSA Fuel Injector System . Fuel Injector . Fuel Air Bleed Nozzle . Magneto Breaker Points . Contact Spring Inspection . Impulse Coupling . Magneto Timing Marks . Engine 'Timing Marks .........•.••.......•................................. Removing Spring From Lead Assembly ..•................................... Assembly Tool ; . Using Assembly Tool .....•................................................ Measuring Lead Assembly Length ' .. Cutting Metallic Braid From End of Lead . Un braiding Metallic Shielding . Forming Shielding Around Ferrule . Ferrule' Seating Tool . Needle " . Measudng Wire From Top of Ferrule . Installing Grommet Over Lead Assemblies' . 2E23 2E24 2E24 2F2 2F3 2F6 2F1 2F1 2F1 2F8 2F8 2F9 2F9 2F9 2FIO 2FIO 2FIO 2FIO 2F 13 2G5 2G8 2GIO 2GI8 2G23 2H4 2H8 2H 11 2H II 2HI3 2H 14 2HI4 2H IS 2H 17 2HI9 2H20 2H20 2H21 2H21 2H21 2H22 2H23 2H23 2H23 2H23 Revised: 10/28/82 IA8 •\ Figure 8A-26. 8A-27. SA-2S. 8A-29. 9-1. 9-2. 9-3. 9-4. 9-5. 9-6. 9-7. 9-8. 9-9. 9-10. 9-11. 9-12. 9-13. 9-14. 9-15. 10-1. 10-2. 10-3. 10-3a. 10-4. 10-5. I 1- t. 11-2. 11-3. 11-4. 11-5. 11-6. 11-7. II-S. 11-9. 11-10. II-It. 11-12. 11-13. 11-14. 11-15. 11- 16. LIST OF ILLUSTRATIONS (conL) Lead Assembly Installed in Grommet . Wire Doubled Over for Installation of Eyelet " " Removing Frozen Spark Plug . Turbo Oil Flow Check ;. Fuel System Schematic (PA-30) .•........................................... Fuel System Schematic (PA-30 Turbo) . Fuel Cell Installation (Main/Inboard) . Fuel Cell Installation (Auxiliary/Outboard) . Checking Sender Unit . Checking Fuel Gauge . Fuel Indicating System Wing Schematic .....................................• Fuel System Installation . Fuel System Installation (Turbo) . Fuel Strainer Assembly . Fuel Selector Installation : . Fuel Selector Valve Control Installation . Weldon Rotary Fuel Pump . Solenoid Valve . Fabricated Fuel Quantity Transmitter Checking Jig . Instrument Panel. Serial Nos. 30-1 to 30-852 incl. and - 30-S54 to 30-90 I incl. . Instrument Panel. Serial Nos. 30-S53. 30-902to 30-1716 incl. and 30-1718 to 30-1744 incl. . Instrument Panel, Serial Nos. 30-1717, 30-1745 to 30-2000 incl. . Securing Pump , . Vacuum System Installation ....•....•....................................... EGT Thermocouple Installation " . Generator Wiring System Schematic . Sectional View of Generator . Wiring Circuit. Dual Regulators ................................•............ Current/ Voltage Regulator . Use of Riffler File to Clean Contact Points . Voltage Regulator Air Gap . Checking Voltage Setting Fixed Resistance Method " . Checking Voltage Setting Variable Resistance Method . Adjusting Voltage Regulator Setting '. Cutout Relay Air Gap Check and Adjustment . Cutout Relay Point Operating Check and Adjustment ; . Checking Cutout Relay Closing Voltage . Adjustment of Cutout Relay Closing Voltage . Checking Current Regulator, Load Method . Checking Current Regulator, Jumper Lead Method . Checking and Adjusting Relay Air Gap~ . "\ Aerofiche Grid ~o. 2H24 2H24 212 214 2124 2J I 2J4 " 2J5 2J II 2J 11 2JI4 2JI5 2J 17 2J20 2J22 2J23 2K2 2K6 2KI0 2Kl6 2Kl7 2KI8 2K24 2L1 2L5 3Al5 3Al9 3A21 384 387 387 388 388 389 3811 38 I I 3812 3812 3813 3813 3816 • •Revised: 10/28/82 lA9 • • ,..... • Figure 11·17. 11-18. 11-19. 11-20. I 1-21. I 1-21. 11-23. 11-24. 11-25: 11-26. 11-:!7. 11-28. 11-29. 11-30. 11-31. 11-32. 11-33. 11-34. 11-34a. II-J5. 11-35a. I 1-.'6. II-.'ba. 11~6b. II-J? I I-JH. II-JC)· II--W. II--tl. II·-t~. 11--tJ. I I-·-t-t. I 1-·-t5. II-··h). I I--t 7. 11-·4k. 12-1. 12-2. LIST OF ILLUSTRATIONS (\:ont.) Aerofiche Grid No. Checking and Adjustinl Relay Point Opening 3816 Checking Relay Oosing Voltage '. . . . . .. 3817 Adjusting Relay Oosing Voltage . . . . . . . . . . . . . . . . . . .. 3817 Alternator Wiring System Schematic 3B 19 Exploded View of Alternator . " 3B21 Removal of Rectifier 3B23 Removal of Slip Ring End Bearing. . '. . . . . . . .. 3B23 Removal of Drive End Head 3B23 Removal of End Head Bearing " 3B23 Testing Rotor for Grounds . . . . . . . . . . . . . . . . . . . . . .. 3B24 Testing Rotor for Shorts 3B24 Installation of Bearing. . . . . . . . . . . . . . . . . . . . . . . . .. 3CI Installation of Rectifier . . . . . . . . . . . . . . . . . . . . . . . .. 3C I Terminal Assembly 3C2 Slip Ring End Bearing Assembly . . . . . . . . . . . . . . . . . . . .. 3C2 Testing Alternator . . . . . . . . . . . . . . . . . . . . . . . . . . " 3C3 Brush Installation ..... ,....................... 3C4 Internal Wiring Diagram . . . . . . . . . . . . . . . . . . . . . .. 3C5 Alternator Paralleling System 3C9 Regulator Diagram (Prestolite) . . . . . . . . . . . . . . . . . . . . .. 3CI4 Regulator Diagram (Lamar) 3CI4 Testing Regulator (Prestolite) 3CI7 Testing Regulator (Lamar) .. . . . . . . . . . . . . . . . . . .. 3C18 Adjusting Regulator (Lamar) . . . . . . . . . . . . . . . . 3C19 Appli\:ation of Ovcrvoltage Control 3C21 Testing Overvoltage Control 3C21 No-Load Test Hookup 301 Lock-TorqueTest Hookup . . . . . . . . . . . . . . . . . 302 Resistan~~ Test Hookup 302 Exploded View of Gear Reduction Starting Motor 306 Turning Starting Motor Commutator .. . . . . . . . . . . . . . .. 309 Testing Motor Armature for Shorts 309 Testing Motor Fields for Grounds . . . . . . . . . . . . . . . . . .. 3010 No-Load TestHookup :........ 3011 Stall-Torque Hookup 3011 Electrical System Components, Serial Nos. 30-1 to 30-852 incl. and 30-854 to 30-.901 3020 Electri\:al System Components. Serial Nos. 30-853, . 30-902 to 10-~OOO, P:\-30 S / N 39-1 . . . . . . . . . . . . . " 3021 ELT Portable Folding Antenna (~arco, , " . . 3G20 ELT Using Fixed Aircraft Antenna (Narco). . . . . . . . . . . . . . . . . . . . . . 3G20 Revised: 6/4/81 1A10 - Figure LIST OF ILLUSTRATIONS (cont.) NOTE Index for Electrical Schematics may be found in Table XI-In, Grid 3E 13. NOTE Aerofiche Grid No. • Index for Electronic Installation Schematics maybe found in Table XII·I, Grid 3G 13. 13·1. 13-2. 13-3. 13-4. 13-5. 13-6. 13-7. 13-8. 13-9. 13-10. 13-11. 13-12. 13-13. 13-14. 13-15. 13-10. 13-17. 13-18. 13-19. 13-~0. 13·21. 13-22. 13-13. 13-24. 13-25. Heating and Ventilating System, Serial Nos. o5U-I to 30-40 I incl . . . . . . . . • . . . . . . . .". . . . . . . . . . . . . Heating and Ventilating System, Serial Nos. 30-402 to 3~852 incl. and 30-854 to 3~901 inel . Heating and Ventilating System, Serial Nos. 30-853, 3~902 to 3~2000 inc! . Heater Installation (South Wind), Serial Nos. 3~1 to 30-401 incl . Flow System (South Wind Heater) . Fllel Control Valve (Cutaway View) . . . . . Wiring Diagram for South Wind Heater. Model 94~DC12 . Fuel Safety Valve (Cutaway View) . Flame Detector Switch (Cutaway View) " Exploded Parts View, Heater Assembly . Ventilating Air Blower Assembly . Ventilating Air Blower Motor . Combustion Air Blower Motor . Detail of Exhaust Extensions Installation ".. Airplane Heater Assembly and Combustion Air Blower . Diagramatic Cutaway of Heater to Show Whirling Flame Action . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Fllel Regulator and Shutoff Valve . Top View - Duct Switch . Wiring Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . Primary Power Circuit . . . . . . . . . . . . . Starting Power Circuit. . . . . . . . . . . . . . . . . . . . . . . Spark Plug Gap Adjustment . Suggested Design for Seal Plate, Plugs and Caps for Combustion Tube Leakage Test " . Test Set-up for Combustion Air Pressure Switch . Exploded View of Heater Assembly No. 751 959 . 4Al3 4Al4 4Al5 4Al8 4A20 4A21 4A22 •4A23 4B2 4Bll 4Bl5 4Bl7 4Bl9 4823 4C7 4C9 4CIO 4CIO 4Cll 4Cl4 4Cl5 4Cl8 408 409 4011 Revised: 4/26/78 1All • • LIST OF ILLUSTRA nONS (cont.) Figure Aerofiche Grid No. • 13-26. 13-27. 13-28. 13-29. 14-1. 14-2. 14-3. 14-3a. 14-4. 14-5. 14-6. 14-7. 14-8. ~4-9 . 14-10. 14-11. 14-12. 14-13. Exploded View-Combustion Air Blower and Motor Assembly No. 753905 ........................................................•.... Suggested Set-up for Heater Operation Test . Wiring Connections for Heater Operation Test .......•........................ Heater Fuel Valve ....................................................•.... Oxygen System Installation. Serial Nos. 30-2 to 30-852 inc!. and 30-854 to 30-90 I inc!. . Oxygen System Installation. Serial Nos. 30-853. 30-902 to 30-1716 inc!. and 30-1718 to 30-1744 inc!. . Oxygen System Installation. Serial Nos. 30-1717. 30-1745 to 30-2000 inc!. . Oxygen Tubing Installations ........•....................................... Synchrophaser Installation . Strobe Sensor . Pulse Generator " . Computer Assembly . Fabricated Test Box .............................................•......... Electrical Schematic . Strobe Sensor Internal Wiring Test Unit . Strobe Sensor Simulator . Patch Cable and Test Terminal . Pulse Generator Simulator . 4015 4017 4018 4020 4E9 4EI0 4EII 4EI8 4E21 4FI2 4F3 4F6 4F7 4F7 4F8 4F8 "4F9 4F9 Revised: 10/28/82 lA12 Table LIST OF TABLES Aerofiche Grid ~o. • II-I. Il-IA. II-II. II-III. II-iliA. II-IV. II-IVA. II-V. II-VI. II-VII. III-I. IV-I. V-I. V-IA. V-Il. VII-I. VII-II. VII-III. VII-I V. VIII-I. VIII-II. VillA-I. VIIIA-ll. IX-I. X-I. X-II. XI-I. XI-II. XI-III. XI-IV. XI-V. XI-VI. XIII-I. XIII-II. XIV-I. XIV-II. Leading Particulars and Principal Dimensions . Flare Fitting Torques . Recommended Nut Torque (lnch-Pounds) . Decimal Conversion Chart ' ' . Indicated Oxygen Pressures for Given Ambient Temperatures . Recommended Lubricating Oils . Thread Lubricant .........•.............................................. Decimal/ Millimeter Equivalents of Drill Sizes " Conversion Tables . Maximum Distance Between Supports for Fluid Tubing . Inspection Report , . List of Materials (Thermoplastic Repair) . Control Surface Travel and Cable Tension . Control Surface :rravel and Cable Tension Air Flow Modification , . Troubleshooting Chart (Surface Controls) . Torque for Effective Wrench Length . Troubleshooting Chart (Landing Gear System) . Main Gear Wear Limits . Nose Gear Wear Limits . Propeller Specifications (PA-30) ........................................•.. Troubleshooting Chart (Engine) . Propeller Specifications (PA-30) . " . Troubleshooting Chart (Engine - Turbocharged) . Troubleshooting Chart (Fuel System) . Troubleshooting Chart (Vacuum System) . Troubleshooting Chart (Instruments) ',' . Troubleshooting Chart (Electrical System) . Lamp Replacement Guide . Index - Electrical System Schematics ' Circuit Load Chart . Electrical Wire Coding ...........•.....................,........•......... Electrical Symbols , . Troubleshooting Chart (South Wind Heater) . Troubleshooting Chart (Janitrol Heater) . Troubleshootin~ Chart (Oxygen System) . Troubleshooting Chart (Engine Synchrophaser) . IBI IB16 1B 18 IB20 ICI9 lC24 IDI ID7 ID8 ID14 IDI9 IF22 IGII IGI2 tJ2 2CI3 2D6 2DI5 2D17 2E7 2FI6 • 2Gl2 216 2K8 2L6 2L8 3E2 3El2 3EI3 3El4 3EI6 3EI7 4C3 4D21 4E 17 4FI0 •Revised: 10/28/82 tAt3 r ' ......... ;- ,'.' '-ltltt:N,r '_ -J.; • •- .-' PART I PA·30 Pan 1 (Gdd lA1S, thru 4F9) contains service information for the PA·30 and PA.. 39 models. See Part II (Grid 401 tIuu 413) for information peculiar to PA·39 model only. Issued: 1~/29 /7'1 1A14 SECTION I •INTRODUCTION Paragraph Aerofiche Grid No. • IAl6 IAl6 IAl6 IAl6 IAl6 lAl7 lAl7 lA17 lA17 lA17 lAlS IAlS lAIS IAlS Fuselage Wing Empennage Flight Cont rols Landing Gca r . Brake System . Engines and Propellers Fuel System. . . . Instruments. . . . . Electronic Equipment . Heating and Ventilating System General Scope of Manual Description 1 -4. 1-5. 1-6. 1 -7. 1 -8. 1 -9. 1-10. 1 -11. 1-12. 1 -13. 1 -14. 1-1. 1-2. 1-3. Issued: 12/29/72 •1A15 • • PIPER TWIN COMANCHE SERVICE MA~1..AL SECfION I INTRODUCfION I-I. GENERAL. This manual contains service and maintenance instructions for the Piper PA-30/39 Twin Comanche, designed and manufactured as a versatile airplane in the personal and business aviation field, by the Piper Aircraft Corporation. Lock Haven. Pennsylvania. 1-2. SCOPE OF MANUAL. Sections 11 and III comprise the service part of this manual. whereas Sections IV through XIV comprise the maintenance instructions. Part II of this manual has service information which is specifically for the PA-39 model only. The servil:e instructions include ground handling, servicing, and inspection. The maintenaOl.:e instructions for each system include troubleshooting, removal and installation of components, and corrective maintenance and testing: each major system of the aircraft is covered in a separate section. Only qualified personnel should perform the operations described in this manual. The description of the airplane included in this section is limited to general information. Section n gives leading particulars and principal dimensions. while each major system is described in its appropriate section of the manual. For a more detailed description of the airplane, refer to the Owner's Handbook. 1-3. DESCRIPTION. The Piper PA-30 Twin Comanche is a four-place (optional 5th and 6th seats are available in Serial Nos. 30-853, 30-902 and up) twin engine, low-wing monoplane of aU-metal construction. P:lragrap~ 14 th~ugh 1-14 provide descriptions of the major components and systems. 14. FUSELAGE. The fuselage consists of three basic units: the nose section, the cabin section. and the tail cone section. 1-5. WING. The laminar flow wing is of all-metal stressed-skin. full-eantilever design . ..:onsisting of two wing panels bolted together at the center of the fuselage. The wing tips are removable. The ailerons are cable and push rod controlled and are statically and dynami..:ally baliinl.:ed. The trailing edge wing flaps are electrically operated. !)';"TRODCCTION lssued: 1-;..::9!7-;' lA16 PIPER TWIN COtvlANCHE SERVICE MANUAL •1-6. E~IPENNAGE. TI,e empennage consists of the fin. rlllJu~r. stabilator and stabilator trim tab. The rudder and staoilator are statically balanced. 1-7. FLIGHT CONTROLS. The flight controls are conventional. consisting of a control wheel which operates the ailerons and stabi1ato~. and foot pedals whil.:h operate the rudder. Duplicate controls are provided for the copilot. " 1·8. LANDING GEAR. The landing gear is an electrically operated tricycle gear. consisting of a nose wheel and two main wheels. 1-9. BRAKE SYSTEM. The brakes on the PA·30 are hydraulically operated by toe pedals. 1·10. ENGINES AND PROPELLERS. The airpiane is powered by two Avcc-Lycoming four cylinder. direct drive. wet sump. horizontally opposed, fuel injected engines. TI,e propellers are Hartzell full feathering, constant speed units controlled by a goverTaor mounted on each engine". Some propellers are equipped with a backup spring which allows operation of the propeller in case of loss of air from the air cylinder. These propellers are identified by the letter "S" after the hub dash number. such as HC·E2YL·2BS. The "5" propeller should not be intermixed with the other propellers. Each model with its engines and particular propellers are as follows: Model Engine Propeller H.P. Octane PA·30 lo-32o-BIA HC·E2YL·2 160 91/96 HC·E2YL·2B HC·E2Yl·2BF HC·E2Yl·2BS HC·E2YL·1BSF p \·)0 T'Irbo lo-3:!O-Cl A HC·E2YL·2 160 100/130 HC·E2YL·2B HC·E2Yl·2BF HC·E2YL·2BS HC·E2Yl·2BSF • INTRODUCTlOt\ Issuei:1: 1:'1':'917'1 • 1A17 • • PIPER TWIN COrvtANCHE. SERVICE MA~UAL t-l1. FUEL SYSTEM. The fuel system consists of four rubber-type cells located in the wings with a total fuel capacity of 90 U.S. gallons. (Optional IS U.S. gallon each, tip tanks) two engine-driven fuel pumps. two electric auxiliarx fuel pumps and two I:ombination fuel selectors and strainer valves. 1-12. INSTRUMENTS. Provisions for the instrument installation includes panels for engine instNments and advance flight instNments. The panel is shock mounted to minimize vibration to the instruments. 1-13. ELECTRONIC EQUIPMENT. Provision for electronic equipment includes vario'.ls combinations of radio installations and AutoPilot. 1-14. HEATING AND VENTILATING SYSTEM. Heated air for the cabin and defroster is obtained from a ~5.000 BTU gasoline heater installed in the nose section. Fresh air for the cabin interior is obtained from two individual sources; one from the nose section and the other from a scoop located in the speed fairing ahead of the vertical fin. L.'\'TR0 DL'CTION Issued: 1~!~917~ 1AlB SECTION II HANDLING AND SERVICING Paragraph •Aerofiche Grid No. 2-1. 2-2. 2-3. 2-4. 2-5. 2-6. 2-7. 2-8. 2-8a. 2-9. 2-10. 2-20. 2-22. 2-29. 2-31. Introduction . Dimensions . Station Reference Lines . Weight and 8alance Data . Serial Number Plate . Access and Inspection Provisions ~ . Tools and Test Equipment . Torque Requirements . Torque Wrenches . Handhold and Walkways . Ground Handling . 2-11. Introduction to Ground Handling ~ . 2-12. Jacking . 2-13. Weighing . 2-14. Leveling . 2-15. Mooring . 2-16. Parking . 2-17. Locking Airplane . 2-18. Towing ....................................................•..•... 2-19. Taxiing . External Power Receptacle . 2-21. Operation of External Power Receptacle . Cleaning .........••.................•.....................•............... 2-23. Cleaning Engine Compartment . 2-24. Cleaning Landing Gear . 2-25. Cleaning Exterior Surfaces . 2-26. Cleaning Windshield and Windows ......................•........... 2-27. Cleaning Headliner, Side Panels and Seats . 2-28. Cleaning Carpets " . Servicing .. , . '" . 2-30. Introduction to Servicing '.' . Landing Gear System . 2-32. Servicing Landing Gear " . IA22 IA22 IA22 IA22 1815 IB 15 IBI5 IB 15 IB17 IB21 IB22 IB22 1822 1823 1823 ICI IC2 IC2 IC2 IC3 IC4 IC4 IC4 IC4 IC5 IC5 IC5 IC6 IC6 IC6 IC6 IC6 IC6 • Revised: 10/18/81 lA19 • Paragraph Aerofiche Grid No. • _ . • 2-33. 2-37. 2-41. 2-43. 2-45. 2-52. 2-56. 2-61. 2-63. 2-67. 2-68. Oleo Struts . 2-.'4. Servicing Oleo Struts . 2-35. Filling Oleo Struts . 2-36. Inflating Oleo Struts . Brake System . 2-38. Servicing Brake System . 2-39. Filling Brake Cylinder Reservoir . 2-40. Draining Brake System . Tires . 2-42. Servicing Tires . Power Plant . 2-44. . Servicing Power Plant . Propeller . 2-46. Servicing Propeller . Power Plant Induction Air Filter . 2-48. Removal of Air Filter . 2-49. Cleaning Induction Air Filter . 2-50. Cleaning Induction Air Filter. Turbocharged . 2-51. Installation of Induction Air Filter . Vacuum System Air Filters . 2-53. Replacement of Central Air Filter . 2-54. Replacement of Instrument Air Filter . 2-55. Replacement of Vacuum Regulator Filters . Fuel Systems . 2-57. Servicing Fuel System ...............................•............. 2-58. Filling Fuel Cells . 2-59. Draining Fuel Valves and Lines ' . 2-60. Draining Fuel System ....................•........................ Electrical System . 2-62. Servicing Electrical System . Oxygen System .•.......................................................... 2-64. Servicing the Oxygen System . 2-65. Oxygen System Safety Precautions . 2-66. Filling Oxygen Cylinder ~ . Lubrication . Oil Systems (Engine) . 2-69. Servicing Oil System . 2-'70. Draining Oil Sump . IC7 IC7 ICg IC9 ICIO ICIO ICIO ICIO ICIO ICIO ICIJ ICIJ ICD ICD ICI.' ICD ICD ICI4 ICI4 ICI5 ICI5 ICI5 ICI5 ICI5 ICI5 ICI5 ICI6 ICI6 ICI7 ICI7 ICI7 ICI7 ICI7 ICI8 ICI9 ICI9 ICI9 IC20 Revised: 10/28/82 lA20 Paragraph ~- 71. ~-72. ~-7J. 2-74. 2-75. 2- 76. 2-77. 2-78. 2-79. 2-80. Revised: 10/28/82 Filling Oil Sump . Oil Screen (Suction) . Oil Screen (Pressure) . Oil Filter (Full Flow) . Turbo Oil Filter Cleaning Procedure . Recommendations for Changing Oil . Lubrication Instructions '" . Application of Oil . Application of Grease . Lubrication Chart . IA21 Aerofichee Grid No. IC20 IC20 IC21 IC21 IC22 IC22 IC23 IC23 IC24 IC24 • • • • •• PIPER TWIN CO~1A:-.ICHE SERVICE MANVAL SECTION II HANDLING AND SERVICING 2-1. INTRODUCTION. This section contains routine handling and servicing pro~edun:s that are most frequently encountered. Frequent reference to this section will aid the: individual by providing infonnation such as the location of various components. ground handling procedures, routine service procedures and lubrication. When any system or component requires service other than the procedures outlined in this section. refer to the appropriate section for that component. 1-2. DIMENSIONS. The principal airplane dimensions are shown in Figures 2-1 and 2-2. and are listed in Table It-I. 2-3 . STATION REFERENCE LINES. In order to facilitate the location of various components of the airplane which require maintenance and servicing, a method utilizing fuselage station. wing station or buttock line (BL), and water line (WL) designations is frequently employed in this manual. (Refer to Figures 2-3 and 2-4.) Fuselage stations. buttock lines, and water lines are reference points measured by inches in the venical or horizontal direction from a given reference line which indicates station locations of structural members of the airplane. Station 0 of the fuselage is located 13.37 inches aft of the foremost point of the nose. Station 0 (BL) of the wing and stabilator is the center line of the airplane; and station 0 (WL) of the fuselage, vertical stabilizer and rudder is 8.25 inches below the bottom edge of the forward left side wi",~ow. The reference datum line or ofuselage station reference line is located 79 inches forward of the wing leading edge. 24. WEIGHT AND BALANCE DATA. When· figuring various weight and balance computations, the weight and empty weight center of gravity of the airplane may be found in the Weight and Balance Form of .the Airplane Flight ~anua1. HANDLING AND SERVICING Revised: 1/31/74 tAll PIPER nVIN COMANCHE SERVICE MANUAL 12' 1.00." --1 1112 • r,I 35'11.151" ----------. II I ....------25' U3T'-------.1 I,\ 1~jE5Jr::::===::::::~~~-" 1\'1~".. \, .... • Figure 2-1. Three View of 1\Yin Comanche PA-30 Serial :--';05. 30-1 to 30-852 inclusive and 30-854 to 30-Q01 inclusi ve HANDUNG AND SERVICI=":C Issued: 12.'29;;: 1 A23 • r • 19U PIPER TIVIN COMANCHE SERVICE MANUAL 35' 11.111"' ----------. !L n Q S' S~500" ---l .--------25' 1.931" -"------ 1 l" 2.11$" ~:;;::::::s~~~~5bEZZ::2F==:::::s~~r.d:- \ \.... • Figure 2-2. Three View of Twin Comanche PA-30 Serial Nos. 30-853, 30-902 to 30-2000 inclusive HANDLING AND SERVICING Issued: 12/29/72 1 A24 PIPER TWIN COMANCHE SERVICE MANUAL TABLE II-I. LEADING PARTICULARS AND PRINCIPAL DIMENSIONS •MODEL ENGINE Manufacturer Model FAA Type Cenificate Rated Horsepower Rated Horsepower, RPM: Full Throttle Performance Cruise (75% rated) 'Economy Cruise (65% rated) Fuel Consumption Cruise 75% Rated Power 65% Rated Power 60% Rated Power Propeller Drive Ratio Propeller Shaft Rotation Bore Stroke Displacement Compression Ratio Weight (With Staner and Generator or Alternator) Dimensions: Height Width Length Oil, SAE Number Oil Sump Capacity Oil Consumption, Maximum Fuel, Aviation Grade, Minimum Octane Fuel Injector, Bendix Magneto (2), Scintilla Magneto Drive, Ratio to Crankshaft Magneto Drive, Rotation Magneto Timing Magneto Point Clearance PA-30 Avco-Lycoming 10-320 BIA IEI2 I 60 160 hp @ 2700 RPM 120 hp @ 2450 RPM 104 hp @ 2350 RPM 10.0 gph 8.8 gph 8.2 gph I: I Clockwise 5.125 in. 3.875 in. 319.8 cu. in. 8.50: I 2871bs. 19.22 in. 32.24 in. 33.59 in. Refer to Table II-III 8 quans 0.010 Ib./bhp/hr. 91/96 octane RSA-5ADI S4LN-21 I: I Clockwise 25 degrees BTC 0.018 + 0.006 • Issued: 12/29/72 181 HANDLING AND SERVICING , .• • PIPER TWIN COMANCHE SERVICE MANUAL TABLE II-I. LEADING PARTICLILARS AND PRINCIPAL DI:-.1El'-:SIONS .- \10DEL E:"JGI:\E Manufacturer Model FAA Type Ct:rtifi~ate Rated Horsepow~r Rated Horsepower. RPM: Full Throttle Performan~e Cruise (75% rated) Economy Cruise (65% rated) Fuel Consumption Cruise 75',~ Rated Power o5:t- Rated Power 60~1 Ratt:d Puwer Prupeller Drive Ratio Propeller Shaft Rotation Bore Stroke Displacement Cllmprcssiun Ratio Weight (With Starter and Generator or Alternator) Dimensions: Hcight \Vidth Length Oil. SA E Numher Oil Sump Capadty Oil Consumption. Maximum Fuel. Aviation Gradt:. \linimum Odanc Fuel Injccror. Bcndix \lagncto (2), Sdntilla \1agm:to Drive. Rario to Crankshafr \lagncto Drive. Rotation \lagneto Tim ing \lag"lletu POlllt eIL'a ralll:C IsslIed: I ~ I ~4 /7 ~ 182 PA -H) Turhu A Vl:O- Lycu/ll ing IO-:UO C I A I EI2 160 160 hp (I 2700 RPM 120 hp (n 2450 RPM 104 hp ((I 23~0 RPM 10.0 gph ~. H gph H.2 gph I : 1 Clockwise 5. 125in. .1.H75 in, :H I.) • ~ l:U. in. K. 50: I 294 Ihs. 11.).22 In. 32.24 in. .3.3 .54 ill, Rder to Tahl t: 1I-1Il 8 qua rls U .llll> 11.>./ bh~/hr. IOIl/I:ill l)l:lane RSA-.:;ADI S4L:\-21 I: I C IUl: k,,'\ Sl' 25 degn.'cs BTC 1I .01 "± I) .1I0o H:\NI)LlNG .\NI) 51·:H \'1l"I\.'C PIPER TWIN COMANCHE SER VICE MANUAL TABLE 11-1. LEADING PARTICULARS AND PRINCIPAL DIMENSIONS (conto) • MODEL ENGINE (I.:ont.) Spark Plugs (shielded): AC Champion Spark Plug Gap Setting (in.) III Firing Order Tachometer Drive. Ratio To Crankshaft Tachometer Drive. Rotation Starter Delco-Remy. 12-volt Prestol ite. 12 -vol t Starter Drive, Ratio to Crankshaft Starter Drive. Rotation Generator. Delco-Remy Voltage Regulator. Delco-Remy Paralleling Relay. Delco-Remy Alternator, Prestolite Voltage Regulator. Prestolite Over Voltage Control, Prestolite Vacuum Pump Drive. Ratio to Crankshaft Vacuum Pump Drive. Rotation Propeller Governor Drive Propeller Governor Ratio Fuel Pump PROPELLER PA-30 SR-88D REM-40E 0.018 to 0.022 in. 1-3-2-4 0.5: I Clockwise Model 110951 I Model MZ420b 13.55:1 Counterc loc lew ise 12-volt, 50 amp. Mudel 1101915 1119246 (50 amp) 1116887 (50 amp) 12-volt, ALX 8403 VSF 7203 HA X17621 1.30: 1 Countercloclcwi se AN20010 Type XX 0.866: I AC-GP644029b • Manufacturer Type Hub Blade (2) Diameter Diameter. Minimum Issued: I ~/~9/7~ 183 Hartzell Constant Speed Feathering HC-E2YL-28. HC-E2YL-2BF. HC-E2YL-~BS 0 HC·E2YL·28SF 7663-4 or F7663-4 72 in. 70 in. HANDLING AND SERVICINIt • PIPER TWIN COMANCHE SERVICE M.A.NUAL TABLE II-I LEADING PARTICULARS AND PRINCIPAL DIMENSIONS ~cont.) • /"-. • MODEL ENGINE (cont.) Spark Plugs (shielded): AC Champion Spark Plug Gap Setting (in.) (II Firing Order Tachometer Drive. Ratio To Crankshaft Tachometer Drive. Rotation Starter Delco-Remy. 12-volt Prestolite. 12 -vol t Starter Drive. Ratio to Crankshaft Starter Drive. Rotation Generator. Delco-Remy Voltage Regulator. Delco-Remy Paralleling Rel~y. Delco-Remy Alternator. Prestolite Voltage Regulator. Prestolite Over Voltage Control. Prestolite Vacuum Pump Drive, Ratio. to Crankst;1aft Vacuum Pump Drive. Rotation Propeller Governor Drive Propeller Governor Ratio Fuel Pump PROPELLER Manufacturer Type Hub Blade (2) Diameter Diameter. Minimum 11 J RE~Ell TO LYCOMING SERVICE INSTRUCTION NO. 10.2. Issued: 1 2/29/72 184 PA-JO Turbo 171 REB-37N 0.015 to 0.021 in. 1-3-2-4 0.5: 1 Clockwise 1109511 MZ4206 13.55:1 Counterc lockw ise 12-volt. 50 amp. Model 1101915 1119246 (50 amp) 1116887 (50 amp) 12-volt. ALX8403 VSF 7203 8A X17621 1.30:1 . Countercl oc kw ise AN20010 Type XX 0.866: 1 Lear-Siegler RG 17980 Hartzell Constant Speed Feathering HC-E:!YL-2B. HC-E:!YL-2BF. HC-E2YL·2BS or HC-E2YL-2BSF 7663-4 or F7663-4 72 in. 70 in. HANDLING AND SER VICING r PIPER TWIN COMANCHE SERVICE MANUAL TABLE II-I. LEADING PARTICULARS AND PRINCIPAL DIMENSIONS (cont.) • ~10DEL PROPELL~R (cont.) Blade Angle, Low (ZI Blade Angle, High lZI Control Governor Governor Model FUEL CELL CAPACITIES Inboard (Main) Fuel Cells Capacity (each) Unusable Fuel (ea~h) Outboard (Auxiliary) Fuel Cells Capacity (each) Tip Tanks Capacity (each) LANDING GEAR Type Shock Strut Type Fluid Required (Struts & Brakes) Strut Extension (Static Load) ~aximum A ir Pressure (Strut) Tread (W idth from each tire center) Wheel Base Nose Wheel Travel Main Wheel Toe-In Turning Radius (Min.) Wheel, Nose Wheel, Main Brake Type Tire. Nose Tire. Main Tire Pressure PA -30 12.0 ± 0.015 degrees 78 degrees Hartzell F6-3 or F6 Two 30 U. S. gallons 3 U. S. ga lions Two 15 U. S. gallons Two (optional) 15 U. S. gallons •Elec trica 11 y retrac ta bl e Combination A ir and Oil MIL-H-5606 (Red) :2. i5 in. 100 psi 9 ft. 9.5 in. 7 ft. 3.625 in. 25° Max. 19° ~1in. right, 25° Max. 19° ~Hn. left o degrees 28 ft. 1.5 in. Cleveland 3850I Cleveland 40-34 III Cleveland 40-90 141 (Disc) Cleveland 30-23 6:00 x 6. 6 ply rated 6:00 x 6, 6 ply rated 42 psi IZIILADE ANG~E AT ]0 'N. RADIUS. ']1 !ER'AL NOS. ]~Z TO J~U5 INCL. Issued: I ~!~9/T~ 14' !ER'AL NOS. l~U6 AND UP. 105 HANDLIN<:;i AND SERVICIN. • PIPER l'~ IN COMANCHE SERVICE MANUAL TABLE II-I. LEADING PARTICULARS AND PRINCIPAL DIMENSIONS (contd) PA-30 MODEL PROPELLER (contd) • ,-. • Blade Angle, Low 2 Blade Angle, High 2 Control Governor Governor Model FUEL CELL CAPACITIES Inboard (Main) Fuel Cells Capacity (each) Unusable Fuel (each) Outboard (Auxiliary) Fuel Cells Capacity (each) Tip Tanks Capacity (each) LANDING GEAR Type Shock Strut Type Fluid Required (Struts & Brakes Strut Extension (Static Load) Maximum Air Pressure (Strut) Tread (Width from each tire center) Wheel Base Nose Wheel Travel Main Wheel Toe-In Turning Radius (Min.) Wheel, Nose Wheel, Main Brake Type Tire, Nose Tire, Main Tire Pressure 2· BLADE ANGLE AT 30 IN. RADIUS. 3 - SERIAL NOS. JO.2 TO JO.845 INeL. 4· SERIAL NOS. 30-846 AND UP. Issued: 12/29/72 12.0 +0.015 degrees 78 degrees Hanzell F6-3 Two 30 U.S. gallons 3 U.S. gallons Two 15 U.S. gallons Two . 15 U.S. gallons Electrically retractable Combination Air and Oil MIL-H-5606 (Red) 2.75 in. 100 psi 9 ft. 9.5 in. 7 ft. 3.625 in. 25t Max. 19t Min. right, 25t Max. 19t Min. left o degrees 28 ft. 11 in. Cleveland 3850 I Cleveland 40-34 3 Cleveland 40-90 4 (Disc) Cleveland 30-23 6:00 x 6, 6 ply rated 6:00 x 6, 6 ply rated 42 psi HANDLING AND SERVICING 186 PIPER TWIN COMANCHE SERVICE ~A:-.iUAL TABLE II-I. LEADING PARTICULARS AND PRINCIPAL DIMENSIONS Icont.) •MODEL OVERALL Gross Weight Gross Weight Landing Width (Spa 1) Length Height (Static Ground Line) Height, Propeller Hub. Thrust Line Level Clearance. Propeller Tips. Thrust Line Level FUSELAGE Length (Including Tail Cone Fairing) Width (Without Stabilator) Height (Without Vertical Fin) WINGS Span (Width) Chord: Station 25 inches Station 62 inches Station 211 inches Dihedl'31 (Leading Edge) Incidence Wing Twist Length of Flap Length of Aileron E\lPENNAGE Stabilator Overall Span Fin Setting, Fixed III PA·lO TURBO ONLY. HANDLING AND SERVICING Revised: 1/31/74 1 87 PA-30. PA-30 Turbo 3600 Ibs.. 37~S Ibs. 111 3600 Ibs .. 3nS Ibsyl 35 ft. 11.75 in. 36 ft. 9.625 inyl 25 ft. 1.9375 in. 8 ft. 2.875 in. 4 ft. 6 in. 11.5 in. 23 ft. 0.950 in. 47.875 in. 53.875 in. 35 ft. 11.75 in. 36 ft. 9.625 in.ll) 7 ft. I in. 5 ft. 5 in. 3 ft. 3 in. 5 degrees 2 degrees odegrees 110.90 in. 75.30 in. 12 ft. 6 in. odegree centerline • •• • PIPER TWIN COMANCHE SERVICE MANUAL TABLE II-I. LEADING PARTICULARS AND PRINCIPAL DIMI':NSIONS Cl:ont.) \10DEL AREAS Total Wing Area (Including Aileron and Flaps) Aileron Flap Stabilator. including trim tab Fin Rudder PA-30. PA-30 Turbo 178 sq. ft. 14.1 sq. ft. 20.2 sq. ft. 32.5 sq. ft. 9.0 sq. ft. 5.9 sq. ft. • • CONTROL SURFACES TRAVEL REFER TOTABLES V-I AND V-IA. CONTROL SURFACE CABLE TENSION REFER TO TABLES V-I AND V-IA . HANDLING AND SERVICING Revised: 1/31/74 188 PIPER TWIN COMANCHE SERVICE MANUAL .'e8 .... ~ (~ . 17"1 .'-./ i l @ I i----!~~ '&1 @ e .... ' @ ----l~ ;:r::;~==1 Y I ; I ~8'" Figure 2-3. Station Reference Lines •. Fuselage • 189 HANDLING AND SERVICING , Issued: 12/29/72 • • • .- • PIPER TWIN COMANCHE SERVICE MANUAL AIIJ .." Figure 2-4. Station Reference Lines, Wing and Stabilator HANDLING AND SERVICING Issued: 12/29/72 1810 PIPER TWIN COMANCHE SERVICE MANUAL • 1775 10. 11 12 SERIAL NOS. 30"1 TO 30-852, 30-854 TO 30-901 INCL. SERIAL NOS. 30-863 AND 30-902 AND UP • 1. ELECTRICAL WIRES, OXYGEN CONTROL CABLE 2. FUSE PANEL 3. ELECTRICAL WIRES, FUEL UNE RIGHT ENGINE 4. LANDING GEAR RETRACTION TRANSMISSION ASSEMBLY 5. ELECTRICAL WIRES. FUEL UNE RIGHT ENGINE 8. FUEL PUMPS. FUEL SELECTOR VALVE CONTROLS 7. MAIN FUEL CEU OUTLET UNE. ELECTRICAL WIRES 8. FUEL SELECTOR VALVES AND DRAINS 9. MAIN GEAR PUSH-PUU CONTROL CABLES. BRAKE UNE. RIGHT GEAR AND TIP TANK FUEL UNE 10. CONTROL CABLE PUUEY CLUSTER. BRAKE UNES, AUTOPILOT PITCH SERVO 11. CONTROL CABLES 12. BRAKE UNES, MAIN FUEL CELL OUTLET UNE, CONTROL CABLES 13. CONTROL CABLE PULLEY CLUSTER, BRAKE UNE LEFT GEAR, TRIM SENSOR. MAIN GEAR PUSH·PULL CONTROL CABLE, TIP TANK FUEL UNE 14. AILERON AND FLAP CONTROL PULLEYS 16. FLAP ACTUATING TRANSMISSION ASSEMBLY. FLAP CONTROL PULLEYS. AUTOPILOT PITCH SERVO 18. ELECTRICAL WIRES, FUSELAGE STRINGERS 17. GYRO AMPUFIER 18. CONTROL CABLES 19. CONTROL CABLES AND PULLEYS, FUSELAGE STRINGERS Figure 2-5. Access. Plates and Panels. Fuselage Interior HANDLING AND SERV1C•. Issued: 1'2/19/ _ 1 811 • PIPER TWIN COMANCHE SERVICE ~1.~~'lJAL " 4 4 I I 5 • 1932 JD c:: =:::-::-.. • 10 1753 13 6 1. NOSE LANDING GEAR 8. VERTICAL FIN ATTACHMENT 80LTS. ELT TRANSMITTER 2. FUEL SELECTOR VALVES. FUEL DRAINS. FUEL SCREENS 9. RUDDER CONTROL HORN. STA81LATOR TORQUE TUBE. 3. MAIN GEAR PUSH-PULL CONTROL CABLES. FLAP POSmON STA81LATOR CONTROL STOPS. STABILArOR TRIM SENDING UNIT MECHANISM 4. MAIN FUEL CELL OUTLET 10. ROTATING BEACON 5. FUSELAGE AFT SECTION INTERIOR 11. STABILATOR BALANCE ARM ANDWEIGHT. STABlLATOR 8. BRAKE FLUID RESERVOIR. CENTRAL AIR FILTER. HEATER CONTROL CABLE ATTACHMENT ENDS. RUDDER TRIM NOSE GEAR. VOLTAGE REGULATORS. PARALLEUNG RELAY BUNGEE 7. OXYGEN FILLER 12. EXTERNAL POWER RECEPTACLE 13. BAGGAGE AREA. BATTERY Figure 2-6. .-'\ccess Plates and Panels, Fuselage P.~ -:30, Serial Nos. 30-1 to 30-852 inel. and 30-854 to 30-901' incl. HA~DLI~G _~~'D SERVICIl':G Issued: 12,'29;72 1 812 PIPER TWIN CO~1ANCHE SERVICE MANUAL • 1i 7.' 4 4 I I ~..J ---J' l.....--J 1115 .11 r-'.~i~ _ ~--: 1. NOSE LANDING GEAR 2. FUEL SELECTOR VALVES. FUEL DRAINS. FUEL SCREENS 3. MAIN LANDING GEAR PUSH·PULL CONTROL CABLES. FLAP ACTUATING TRANSMISSION FLAP POSITION SENDER UNIT. AUTOPILOT 4. MAIN FUEL CELL OUTLET 5. EXTERNAL POWER RECEPTACLE 6. BATIERY. VOLTAGE REGULATOR. BRAKE FLUID RESERVOIR. CENTRAL AIR FILTER HEATER. NOSE GEAR. PARALLELING RELAY 7. BAGGAGE AREA 8. OXYGEN FILLER 9. VERTiCAL FIN ATIACHMENT BOLTS. ELT TRANSMITIER 10. RUDDER CONTROL HORN STABILATOR TORQUE TUBE. STABILATOR CONTROL STOPS. STABILATOR TRIM MECHANISM 11. ROTATING BEACON 12. STABILATOR BALANCE ARM AND WEIGHT. STABILATOR CONTROL CABLE ATIACHMENT ENDS. RUDDER TRIM BUNGEE • Figure 2-7. .o\ccess Plates and Panels, Fuselage .PA-30, Serial Nos. 30-853, 30-902 to 30-2000 inclusive HANDLING A~D SERVlCI. lssu~d: 1:!2917- 1813 • PIPER TWIN CO\LAi'iCHE SERVICE \1.\:'\L.-\l. 1. PROPELLER RECHARGE VALVE 2. OIL FILLER 3. VACUUM REGULATOR, ENGINE CONTROL CABLES AND ELECTRICAL WIRE CONNECTIONS 4. FUEL CELL MAIN 5. FUEL CELL FILLER. MAIN 6. NACELLE INTERIOR 7. FUEL CELL. AUXILIARY 8. FUEL CELL FILLER. AUXILIARY 9. WING TIP 10. ENGINE CONTROL CABLES. ELECTRICAL WIRE CONNECTORS. FUEL LINE CONNECTIONS. STATIC AIR LINE CONNECTIONS. BRAKE LINE CONNECTIONS AND FRONT AND REAR SPAR ATTACHMENT POINTS 11. ENGINE OIL DRAIN 12. FUEL CELL OUTLET AUXILIARY 13. MAIN LANDING GEAR AND BRAKE ASSEMBLY 14. BUNGEE CORD 15. FLAP BELLCRANK 16. AILERON CABLE PULLEYS 17. AILERON BELLCRANK 1 B. PITOT TUBE 19. STEP LOCK ADJUSTMENT ;'.. - Figure 2-8. Access Plates and Panels, Wings H.\~DLlNG .\~ SERV1CI~G Issu~d: I 2,"':'9 /7 ~ 1 814 .-I PIPER TWIN COMANCHE SERVICE MANUAL •2-5. SERIAL NUMBER PLATE. The serial number plate on the PA-30 can be found at the following locations: On the forward upper portion of the forward cabin bulkhead: inside the fuselage on the left skin opposit~ the rear fuselage access panel: or on the fuselage adjacent to the left side of the tail skid. Airplan~ serial numbers will be used in this manual· where servicing difference occurs. and should be used wilen contacting the factory on service or warranty matters. 2-6. ACCESS AND INSPECTION PROVISIONS. The access and inspection provisions for the airplane are shown in Figures 2-5 thru 2-8. The component to be serviced or inspected through each opening is assigned an index. number to identify it in the illustration. All access plates and panels are secured by either metal fasteners or screws. The floor panels may be removed by first removing the desired seats. then sliding the carpet edges from under its retainer strips. lifting the edges and removing the carpet attaching screws. Remove the carpet. thus exposing the floor panel attaching screws. To enter the aft section of the fuselage. remove the lower rear baggage compartment upholstery panel by removing the attaching screws. CAUTION Before entering the aft section of the fuselage. be sure the airplane is supported at the tail skid. 2-7. TOOLS AND TEST EQUI PM ENT. Because of the simplicity and easy accessibility of components. few special tools outside normal shop tools will be required. Tools that are required may be fabricated from dimensions given in the back of the section that pertains to a particular component or are listed in the back of the PA-30 Parts Catalog. 2-8. TORQUE REQUIREMENTS. The torque values given in Table II-II are derived-from oil-free. cadmium-plated threads and are recommended for all airframe installation procedures where ton.lueing is required. unless otherwise noted in sections where other values are stipulated. Engine torque values are found in the latest revision of Avco-Lycoming Service Bulletin No. 268. Propeller torque values are found in Section VIII of this manual. Table II-Ia lists the torque valves for flared fittings of various sizes and material. • Revised: 10/27/82 1815 HANDLING AND SERVICING • . • PIPER TWIN COMANCHE SERVICE MANUAL CAUTION Do not overtorque fittings. NOTE When flared fittings are being installed. ascertain that the male threads are properly lubricated. Torque the fittings in accordance with Table II-IA. TABLE ll-IA. FLARE FITTING TORQUES TORQUE I!'CH-POUND lTHI:\(i Al.UMI:\l'M - ALLOY STEEL. Tl'UI:\(j HOSE E:\D FITTI:\(j OD Tt'Rl:\(i .·TARE - A~D FI.ARE Al'iD I:\CH ES IOOh I () R A' [) 1007X A~D 100fli HOSE ASSEMUI.IES '- MI'I"il'M MAXIMUM MI'IMUM MAXlMl:M MINlMl'M MAXIMliM I/X --- --- --- --- --- --- .'/Itt --- --- 9.0 100 70 100 1/4 40 65 1.'5 ISO 70 120 5/1 fl (,0 XO IXO 200 1<5 11<0 .l/ x 75 125 270 .lOO 100 250 1/2 150 250 450 500 210 420 5/X .200 35O fl50 700 .'00 41<0 .l/4 .'()() 500 900 \(100 500 1<50 I 500 700 1200 1400 700 1150 1-1/4 hOO 900 --- --- --- --- 1-1/2 h(K) 900 --- --- --- ---1-3/4 --- --- --- --- --- ---2 --- _._- --- --- --- --- • Added: 10/18/81 IB16 HANDLING AND SERVICING TWIN COMANCHE SERVICE MANUAL ---.---------.2-8a. TORQUE WRENCHES. Torque wrenches should be checked daily and calibrated by means of weights and a measured lever arm to make sure that inaccuracies are not present. Checking one torque ~rench against another is not sufficient and is not recommended. Some wrenches are quite sensitive as to the way they are supported during a tightening operation. Any instructions furnished by the manufacturer must be followed explicitly. When it is necessary to use a special extension or adapter wrench together with a torque wrench. a simple mathematical equation must be worked out to arrive at the correct torque reading. Following is the formula to be used: (Refer to Figure 2-8a.) T =Torque desired at the pan. A =Basic lever length from center of wrench shank to center of handle or stamped on wrench or listed for that model wrench. B =Length of adapter el(tension, center of bolt to center of shank. C =Scale reading needed to obtain desired torque en. The formula: C = A l( T A+B EXAMPLE T A bolt requires 30 foot-pounds and a 3 inch adapter (one-quarter of a foot or .25') is needed to get at it. You want to know· what scale reading it will take on a one-foot lever arm wrench to obtain the 30 foot-pounds at the bolt. C - I l( 30 C - 30 - 24 ft Ib .. - I + .25 or - TIS - .- s. Remember, the 3 inch adapter must be projecting 3 inches straight along the wrench axis. In general, avoid all complel( assemblages or adapters and extensions of flex joints. -- ....~-------A---------t~ Figure 2-81. Torque Wrench Formula • Added: 10/28/82 IB17 HANDLING AND SERVICING PIPER TWIN COMANCHE SERVICE MANUAL TABLE II-II. RECOMMENDED NUT TORQUE (INCH-POUNDS) TABLE B COARSE THREAD SERIES BOLTS StMI Tension AN 3 thru AN 20 AN 42 thru AN 49 AN73 thru AN 81 AN 173 thru AN 186 MS 20033 thru MS 20046 MS 20073 MS 20074 AN 509 NK9 MS 24694 AN 525 NK525 MS 27039 NUTS 9 15 30 SS 110 155 290 420 540 950 1.800 3.000 4.000 5.000 Max. AN 320 AN 364 NAS 1022 MS 17826 MS 20364 Steel Shear 7 12 25 48 95 140 240 300 420 700 1.300 2.200 3.300 4.000 Min. Torque Limits in·lb. 15 2S 50 90 185 2SS 480 700 900 1.600 3.000 5.000 6.500 8.000 Mall. AN 310 AN 315 AN 363 AN 385 NAS 1021 MS 17825 MS 21045 MS 20365 MS 20500 NAS 679 12 20 40 80 160 235 400 500 700 1.150 2.200 3.700 5.500 6.500 Min. StHI Tension Torque Limit. in·lb. /IIut-bolt siza 8 -32 10 -24 114-20 5/16-18 3/8-18 7/16-14 1/2-13 9/16- 12 5/8- 11 3/4-10 718- 9 1 -B 1-118-8 1·114-8 BOLT FRICTION DRAG SIZE TORQUE IIN.LBS.I 8 0 ' 15 10 18 1/4 30 5/16 60 : 3/8 80 7/16 100 TABLE A "APPLICABLE TO COARSE THREADS ONLY . TORQUES: The Importance of correct application cannot be overemphasized. UndertorQue can resull in unnecessary wear of nuts and bolts as well as the parts they are holding together. When insufficient pressures are applied, uneven loadswill be transmilled throughout the assembly which may result in 8Jlcessive wear or premature failure due to fatigue. OvertorQue can be equally damaging because of failure of a bolt or nut from overstressing the thread areas. The following procedures should be followed to assure that the correct torque is applied: ,. Torque (self·locking fasteners)·Add the friction torque from Table A from sizes 8 through 7/16 to the recommended torque from Table B to get the final torque. This would be the actual reading on the torque wrench. 2. Torque (castellated and non·self.locking nuts)·Use only the torque given in Table B. Unless otherwise specified. when castellated nuts are used with a COller pin on moving joints. do not torque the nut. Turn the nut onto the bolt until proper. grip is established and alignment with the COller pin hole is achieved. then install the COlter pin. 3. Calibrate the torque wrench periodically to assure accuracy: recheck frequently. 4. Ascertain that the bolt and nut threads are clean and dry (unless other· wise SPecified by the manufacturel. If the bolt or nut is specified to be lubricated prior to tightening. the torque range should be reduced 50%. 5. Use a bolt length long enough to prevent bearing loads on the threads. The complete chamfer or end radius of (he bolt or screw must extend through the nut. . 6. Unique torques specified in the text of· this manual supersede the torques given in Tables A and B. 7. Refer to the latest revision of Lycoming SSP1776 for torques on parts used on Lycoming engines. 8. A maximum of two AN960 washers may be added under the bolt heads or nuts to correct for variations in material thickness within the tolerances permitted. 9. LimItatIons ~f the use of self· locking nuts. bolts and screws including fasteners with non·metallic inserts are as follows: A. ~asteners incorporating self·locking devices shall not be reused if they can be run up using only fingers. They may be reused if hand tools are required to run them up. providing there is no obvious damage to the self-locking device prior to installation. B. Bolts 5/16 inch diameter and over with cotter pin holes may be used with self· locking nuts. Nuts with non-metallic locking devices may be used in this application only if the bolts are free from burrs around the cotter pin hole. C. Do not use self· locking nuts at joints which subject either the nut or the bolt to rotation. D. Never tap or rethread self-locking fasteners. Do not use nuts. bolts or screws with damaged threads or rough ends. • ., .• '-.. i· l , Revised: 10/28/82 1B18 HANDLING AND SERVICING PIPER TWIN COMANCHE SERVICE MANUAL TABLE II-II. RECOMMENDED NUT TORQUE (INCH POUNDS) (cont.) BOLTS BOLTS BOLTS Steel Tension Stili Tension Aluminum AN 3 thru AN 20 MS 20004 thru MS 20024 AN 300 thru AN 2OD0 AN 42 thru AN 49 NAS 144 thru NAS 158 AN 17300 thru AN 18600 AN 73 thru AN B1 NAS 333 thru NAS 340 AN 60900 AN 173 thru AN 188 NAS 583 thru NAS 590 AN 6260 MS 20033 thru MS 20048 NAS 624 thru NAS 644 MS270390 MS 20073 NAS 1303 thru NAS 1320 MS2469400 MS2oo74 NAS 172 AN 609NK9 NAS 174 MS 24694 NAS 517 Steel shill' bolt AN 526NK625 MS 27039 NAS 464 NVTS NUTS NUTS Steel Tension SteelShur StMl Tension Stell Sheer Alum. Tension Alum.She. AN 310 AN 320 AN 310 AN 320 AN 3660 AN 3200 AN 315 AN 364 AN 315 AN 364 AN 3100 AN 3640 AN 363 NAS 1022 AN 363 NAS 1022 NAS 10210 NAS 10220 AN 36& MS 17B26 AN 366 MS 17826 NAS 1021 MS 20384 MS 17825 MS 20364 MS 17826 MS"20386 MS 21046 MS 21046 MS 20366 NAS 1021 MS 20600 NAS679 NAS 679 HAS 1291 FINE THREAD SERIES Nut-bolt Torque Llmitl Torque Llmitl Torque Llml.. Torque Limits Torque Llml.. Torque Limit. i1ze In-ibi In-ibi In-lb. In-lb. In-lb. In-ibi Min. Mu. Min. Mu. Min. Mu. Min. Mu. Min. Mu. Min. MI•. 8 -36 12 16 7 9. 6 10 3 6 10 -32 "20 26 12 16 26 30 16 20 10 15 5 10 1/4-28 50 70 30 40 80 100 50 60 30 46 16 30 5118-24 100 140 60 86 120 146 70 90 40 66 26 40 3/8-24 160 190 95 110 200 250 120 150 76 110 46 70 7/18-20 460 600 270 300 520 630 300 400 180 280 110 170 1/2-20 480 690 290 ",0 770 950 460 550 280 410 uio 260 9/18-18 800 1.000 480 6C)O 1.100 1.300 660 800 380 680 230 360 6/8-18 1.100 1.300 660 780 1.260 1.560 760 960 660 870 270 420 3/4-16 2.300 2.500 1.300 1.500 2.660 3.200 1.600 1.900 960 1.250 560 880 7/8-14 2.600 3.000 1,500 UOO 3.550 4,360 2.100 2,690 1.260 1.900 750 1,200 1 -14 3.700 4.500 2.200 3.300 4,500 6,500 2.700 3.300 1.600 2.400 960 1,500 1·118-12 5.000 '7.000 3,000 4.200 6.000 7,300 3.600 4.400 2.100 3.200 1.250 2,000 1.1/4-12 9;000 11,000 6,400 6,600 11,000 13,400 6.600 B.Ooo 3.900 6,800 2,300 3.660 • • Revised: 1/31/74 IB19 HANDLING AND SERVICING PIPER TWIN COMANCHE SERVICE MANUAL TABLE ll-ill DECIMAL CONVERSION CHART • 4TM' en.. 1&M. 32lCII 64Tlll TO. TO I ......~uc •• ~1....CII IQUIY. 1 .016 .02 .3971 ~ n .031 .03 .794 Ii A- .047 .os 1.191 .062 .06 1.587 f2 d- .078 .08 1.984 .094 .09 2.381 1 la- .109 .11 2.718 8 .125 .12 3.175 i._ .141 .14 3.Sn ~ 64 .• 156 .16 3.969 fa ~- .1n .17 4.366 .188 .19 4.762 12· a· .203 .20 5.159 ~ .219 .22 5.556 ~- .234 .23 5.593 1 64 ~ .250 .25 6.350 lZ- .266 .27 6.7479 64 .281 .28 7.144 ~ ;t ~- .297 .30 .7.540 .312 .31 7.937 11 11- .328 .33 8.334 32 .344 .34 8.731 t H· .359 .36 9.128 .375 .38 9.525, ~- 13 64 .391 .39 9.922 ~ .406 .41 10.319 ~ B· .422 .42 10.716 .438 .44 11.112 15 8- .453 .45 11.509 ~ .469 .47 11.906 31 .484 .48 12.303 64' .500 .50 12.700 4TM' en.. ~&M' 3Zlm 64ru TO' TO I ..... , ~UCI' ~""'C" IQUllI'. 11 ~- .516 .52 13.097 32 .531 .53 13.494 f~ H- .547 .55 13.891 .562 .56 14.288 If H- .578 .58 14.684 .594 .59 15.081 f H- .609 .61 15.478 .625 .62 15.875 21 t!- .641 .64 16.2n ~ .656 .66 16.669 11 B- .6n .67 17.065 i! .688 .69 17.462 23 !i- .703 .70 17.859 n .719 .n 18.256 47. .734 .73 18.653 .3. t;4 .750 .75 19.050 4 4~_ .766 .71 19.44725 ~ ~ .781 .78 19.844 13 ~- .797 .80 20.241 f! .812 .81 20.637 27 ~- .828 .83 21.034 ~ .844 .84 21.431 7 ~. .859 .86 21.828 s- .875 .88 22.225 29 H- .891 .89 22.622 .~ .906 .91 23.019 1S H- .922 .92 23.416 i6 .938 .94 23.812 H ~- .953 .95 24.209 .969 .97 24.606 ~- .984 .98 25.003 1.000 1.00 25.400 '. HANDLING AND SERVICING Issued: 1'J.t~9/72 IB20 '-"" ( PIPER TWIN COMANCHE SERVICE 7-.1A(\;UAL 2-9. HANDHOLD AND WALKWAYS. A fixed handhold is located on the right side of the fuselage. above the rear window. W31~"Ways of four parts Dl;:vol;: n(,n- skid compound and one part black enamel are painted on the right wing ano flap. The lines of rivets on the walkway are covered with non-skid paper strips, St:- cured with sculp-metal compound before the walk is appl ied. CAUTION Avoid damage to the wings by stepping only on the walkway. HA~'DL1~G ..\NO SERVICING Issued: I :r~9/7'1 IB21 • • • TWIN COMANCHE SERVICE MANUAL Figure 2-9. Jacking Arrangements 2-10. GROUND HANDLING. 2-11. INTRODUCTION TO GROUND HANDLING. Ground handling covers all essential information governing the handling of the airplane while on the ground. This includes jacking, weighing, leveling, mooring, parking, towing and taxiing. When the airp~ane is handled in the manner described in the following para- graphs, damage to the airplane and its equipment will be prevented. 2-12. JACKING. The airplane is provided with a jack pad on each main spar just outboard of the engine nacelle and a support position by making use of the tail skid. (Refer to Figure 2-9.) To jack the airplane, proceed as follows: a. Place the jacks under the jack pads. b. Attach the tail support to the tail skid. Place approximately 350 pounds ofballast on the support to hold the tail down. CAUTION Be sure to apply sufficient tail support ballast: otherwise the airplane will tip forward and fall on the fuselage nose section. c. Raise the jacks evenly until all three wheels clear the floor. ••, Revised: 10/28/82 IB22 HANDLING AND SERVICING PIPER TWIN COMANCHE SERVICE MANUAL -----------.A263 Figure 2-10. Weighing Airplane 2-13. WEIGHING. (Refer to Figure 2-10.) The airplane may be weighed by the following procedure: a. Position a scale and ramp in front of each of the three wheels. b. Secure the scales from rolling forward and tow the airplane up onto the scales using the towing procedure as given in paragraph 2-18. c. Remove the ramp so as not to interfere with the scales. d. If the airplane is to be weighed for weight and balance computations, level the airplane per instructions given in paragraph 2-14. 2-14. LEVELING. All configurations of the airplane are provided with a means for longitudinal and lateral leveling. The airplane may be leveled while on jacks, during the weighing procedure while the wheels are on scales. or while the wheels are on the ground. To level the airplane for purposes of weighing or rigging. the following procedures may be used: a. To longitudinally level the airplane, partially withdraw the two leveling machine screws on the side of the fuselage. On airplanes with Serial Numbers 30-1 to 30-852 inclusive and 30-854 to 30-90 I inclusive, the screws are located over the baggage door. (Refer to Figure 2-11.) On airplanes with Serial Numbers 30-853 and 30-902 to 30-2000 inclusive, there is one screw fore and one aft of the right rear window. (Refer to Figure 2-12.) Place a spirit level on these screw heads and adjust the jacks until the level is centered. Should the airplane be either on scales or on the floor, first block the main gear oleos toJull extension; then deflate the nose wheel until the level position is reached. • r Revised: 10/28/82 IB23 • HANDLING AND SERVICING PIPER -twIN COMANCHE SERVICE ~tANUAL • AU' ~ r-"" da #D$§ ,'£] ""I: .\ j. l I Figure 2-11. Leveling Airplane Serial Nos.. 30-1 to 30-852 inc1; 30-854 to 30-901 inci. • AU' AUG -~-.- =. • Figure 2-12. Leveling Airplane Serial Nos. 30-853, 30-902 to 30-2000 inclush'e HANDLING A~l) SERVICli\G. Issued: 1:'/~9 Ii ~ IB24 PIPER TWIN COMANCHE SERVICE \1ANL'AL b. To later:llly level airplanes with Serial Numbers 30-1 to 30-852 inclusive and 30-854 to 30-90 I inclusive. place a level Jcross the floorboard at Station 136.5 over the bulkheau to whi~h the baggage door hinge br:lckets are atta~hcd. fRefer to Figure ~·ll.) On airplanes with Serial ~umbers 30-853 and 30-90~ to 30-~OOO inclusive. place a level on or p:u:.Illd to the hat section channel oi the forward cabin bulkhead. (Refer to Figure 2-12.1 Should equipment or other obstacles hinder placing the level directly on the channel. use two spacers (rods. etc.) of equal length between the level and channel to bring the level abov~ ilny obstacles. Raise or lower one wing til' by deflating the appropriate tire on the high side of the airplane or adjust either jack until the bubble of the level is centered. 2·1 S. MOORING. The airplane should be moored to insure its immovability. protection and security under various weather conditions. The following procedure gives the instructions for proper mooring of the airplane. a. Head the airplane into the wind, if possible. b. lock the aileron and stabilator controls using the front seat belt. control whed lo~k. or control surface blocks. c. Block the wheels. d. Secure tie-down ropes to the wing tie-down rings and the tail skid at approximately 4S-degree angles to the ground. leave sufficient slack to avoid damage to the aircraft when the ropes contr.lct due to moisture. CAUTION Use square or bowline knots. Do not use slip knots. NOTE Additional prenarations for high wind~ include :.lsing tie-down ropes from the landing gear forks. and securing the rudder. e. lnstalll,itot tube cover. if possible. H.~:-':DLlNG AND SERVICING Issued: I ~r~9/72 leI • • • • • • PIPER TWIN COMANCHE SERVICE MANUAL 2-16. PARKING. When parking the airplane, insure that it is sufficiently pro- tected against adverse weather conditions and presents no danger to other air- craft. When parking the airplane for any length of time or overnight, it is rec- 0mmended that it be moored as in paragraph 2-15. a. To park the airplane, head it into the wind, if possible. b. Set the parking brake by applying toe pressure against the top of the brake pedals and at the same time pull out an the brake handle. To release the parking brake, apply toe pressure on the pedals and push in on the parking brake handle. NOTE To prevent damage to brake drum, care should be taken when setting brakes that are overheated or during cold weather when accumulated moisture may freeze the brake. . 2- 17. LOCKING AI;RPLA NE. The cabin and baggage doors are provided with a key lock. The same key can be used to operate both door locks. 2-18. TOWING. The airplane may be moved by using the nose wheel steering bar provided, or power equipment that will not damage or cause excess strain to the nose gear assembly. On airplanes with Serial Numbers 30-1 to 30-852 inclu- sive, the steering bar is stowed on the underside of the hat shelf in the baggage compartment. On airplanes with Serial Numbers 30-853 and 30-902 to 30-2000 inclusive, it is attached to the forward section of the main spar. CAUTION When towing with power equipment, do not turn nose gear more than 20-degrees in either direction as this will result in damage to the nose gear and steering mechanism . HANDLING AND SERVICING Issued: I ~.':9iT;' te2 PIPER TWIN COMANCHE SERVICE MANUAL .' r IIU • Figure 2-13. Minimum Turning Radius 2 -19. TA XUNG. Before attempting to taxi the airplane, gTound personnel should be checked out by a qualified pUot or other responsible person. Engine starting and shut-down procedures should be covered as well. When it is ascertained that the propeller back blast and taxi areas are clear. apply' power to start the taxi roll and perform the following checks: a. Taxi forward a few feet and apply brakes to determine their ettectiven~ss. b. Taxi with propeller set in low pitch. high RPM setting. 1.:. While taxiing. make sUght turns to ascertain the effectiveness of ste~ring . d. Observe wing clearances when taxiing near buildings or other stationary objects. If possible. station a guide outside the airplane to observe. e. When taxiing on uneven ground. look for holes and ruts. i. Do not operate the engine at high RPM when running up or taxiing over ground containing loose stones. gravel or any loose material that may cause damage to the propeller blades. HANDLING AND SERVICING Issued: I ~r29/7'1 lC3 • • • • PIPER TWIN COMANCHE SERVICE MANUAL 2-20. EXTERNAL POWER RECEPTACLE~ 2-21. OPERATION OF EXTERNAL POWER RECEPTACLE. The external power receptacle is located on the right side of the fuselage, just rearward of the bag- gage door. on airplanes with Serial Nos. 30-2 to 30-852 inclusive and 30-854 to 30-901 inclusive: and on the left side of the nose section of airplanes with Serial Nos. 30-853 and 30-902 to 30-2000 inclusive. When using external power for starting or operation of any of the airplane's equipment, place the master switch in the OFF position before inserting or removing the power plug. 2-22. CLEANING . .2-23. CLEANING El'KIINE COMPARTMENT. Before cleaning the engine com- partment, place a st.rip of tape on the magneto vents to prevent any solvent from entering these units. a. Place a large pan under the engine to catch waste. b. With the engine cowling removed, spray or brush the engine with solvent or a mixture of solvent and degreaser, as desired. It may be necessary to brush areas that were sprayed where heavy grease and dirt deposits have collected in order to clean them. CAUTION Do not spray solvent into the generator or alternator, staner, or air intakes. C. A How the solvent to remain on the engine from five to ten minutes, then rinse rh~ ~ngine clean with additional solvent and allow to dry. "CAUTION Do not operate engine until excess solvent has evapo- rated or otherwise been removed. d. Remove the protective covers from the magnetos. e. Lubricate controls, bearing surfaces, etc.. per Lubrication Chart, Figure 2-20. HANDLING A:-ID S'ERVICING Issued: 1'2(29;'7'2 lC4 r-. PIPER TWIN COMANCHE SERVICE MANUAL 2-24. CLEANING LANDING GEAR. Before cleaning the landing gear. place a plastic cover or similiar material over the wheel and brake assembly. a. Place a pan under the gear to catch waste. b. Spray or brush the gear area with solvent or a mixture of solvent and degreaser, as desired. It may be necessary to brush areas that were sprayed wbere heavy grease and din deposits have collected in order to clean them. c. Allow the solvent to remain on the gear from five to ten minutes. then rinse the gear with additional solvent and allow to dry. d. Remove the cover from tbe wheel and remove the catch pan. e. Lubricate the gear per Lubrication Chan, Figure 2-20. 2-25. CLEANING EXTERIOR SURFACES. The airplane should be washed witb a mild soap and water. Harsh abrasive or alkaline soaps or de~ergenu used on painted or plastic surfaces could make scratches or cause corrosion of metal surfaces. Cover ~reas where cleaning solution could cause damage. To wash the airplane. the following procedure may be used: NOTE When hosing do~ aircraft avoid directing water in the fuel tank vents, drain tubes or around the sealed cover plates and filler cap access openings. a. Flush away loose dirt with water. b. Apply cleaning solution witb a rag, sponge or soft bristle brush. c. To remove stubborn oil and grease, usc a cloth dampened with naptha. d. Where exhaust stains exist, allow solution to remain on the surface longer. e. . Any good automotive wax may be used to preserve the painted surfaces. Soft cleaning cloths or a chamois should be used to prevent scratches when ~eaning or polishing. A heavier coating of wax on the leading surfaces will reduce the abrasion problems in these areas. 2-26. CLEANING WINDSHIELD AND WINDOWS. a. Remove din, mud, etc., from exterior surface with clean water. b. Wash with mild soap and warm water or on aircraft plastic cleaner. Usc a 50ft cloth or sponge using a straight rubbing motion. Do not harsbly rub surfaces. c. Remove oil and grease with a cloth moistened with kerosene. NOTE Do not use gasoline. alcohol. benezene. cabon tetrachloride, tbinner, acetone, or window cleaning sprays. HANDLING AND SERVICING Revised: 9/10,79 lC5 • • • • • • PIPER TWIN COMANCHE SERVICE- MANUAL d. After cleaning plastic surfaces. applya thin coat ofhardtpolishing wax. Rub lightly with a soft cloth. Do not use a circular motion. e. A severe scratch or mar in plastic can be removed by using jeweler's rouge to rub out the scratch. Smooth hoth sides and apply wax. f. To improve visibility through windshield and windows during flight through rain. a rain repellent such as REPCON should be applied to the windshield and windows. The surfaces of the windshield and windows treated becomes so smooth that water beads up and readily flows off the surface. Apply this product in accordance with the manufacturer's instructions. (Repco P / N FSCM. made by (J NEL KO Corporation 727 E. IIOth Street Chicago, 111.60628.) 2-27. CLEANING HEADLINER, SIDE PANELS AND SEATS. a. Clean headliner. side panels and seats with a stiff bristle brush and vacuum where necessary. b. Soiled upholstery. except leather. may be cleaned by using an approved air type cleaner or foam upholstery cleaner. Carefully follow the manufacturer's instructions. Avoid soaking or harsh rub.bing. CAUTION Solvent cleaners require adequate ventilation. c. Leather material should be cleaned with saddle soap or a mild soap and water. 2-28. CLEANING CARPET. Use a small whisk broom or vacuum to remove dirt. For soiled spots, use a non-inflammable dry-cleaning fluid . 2-29. SERVICING. 2-30. INTRODUCTION TO SERVICING. Servicing the airplane includes the replenishment of fuel. oil. hydraulic fluid, tire pressures. lubrication requirements and other items required to completely service the airplane. 2-31. LANDING GEAR SYSTEM. 2-32. SERVICING LANDING GEAR. The landing gear consisting of tires, brakes. oleo strut assembly. drag links. down locks and gear doors should be visually inspected to determine proper strut extension. possible hydraulic fluid leakage, security and condition of all related components. Minor service is described in the following paragraphs. and detailed service and overhaul instructions are listed in Section VII. Revised: 10/28/82 lC6 HANDLING AND SERVICING PIPER TWIN COMA NCIIE SEHVICE MANL'AL • C21Z r-- I Figure 2-14. Servicing Landing Gear Struts 2-33. OLEO STRUTS. ~-34. SERVICING OLEO STRUTS. The: air-oil type oleo strut should be maintained at proper stnH tube exposures for best oleo action. Both the noSl:! and main gear struts must have approximately 2.75 inches of piston tube exposed. (Refer to Fil'Jre 2-14.) These measurements are taken with the airrlane sitting on level surface under normal ~tatk load. (Empty weight of airplane plus full fuel and oiL) If the strut has less tube exposure than prescribed. determine whether it needs air or oil by rocking the airplane. If the oleo stnlt osc:ilIates with short strokes (approximately one inch) ana the airplane ~ttles to its normal position within one or two cycles after t~e rocking fon:e is removed. th.: oleo strut requires inflating. Check the valve core and fille:r plug for air leaks. correct if reqllired. and add air as described in p:lragr:lph 2·36. If the oleo stnlt oscillates with long strokes (approximately three inches) and the airplane continues to oscillate after the ro\:king force is removed. the oleo stnlts require fluid. Check the oleo for indications of oil leaks. correct if requireu. anu add fluid as described in paragr:lph ~·3..5. For repair procedures of the landing gear anu/nr 01"·0 stnlts. refer to Section VII. WARNING Deflate strut before disassembly. HANDLING AND SERVICING Revised: 4/6/81 le7 • • • • • PIPER TWIN COMANCHE SERVICE MANUAL 1-35. FILLING OLEO STRUTS. To fill the nose or main gear oleo strut with i1uid o.UL-H-5606), whether it be only the addition uf a small amount or if the unit has been completely emptied and will require a large 3nlOunt, it should be filled as follows: W.\RNI~ Do not release air by r.emoving the strut valve core or filler plug. Depress the valve core pin until strut chamber pressure has diminished. CAUTION Dirt and foreign particles form around the filler plugs of the landing gear struts. therefore. before attempt- ing to remove these plugs. the tops of the strUts should .be clea.ned with compressed air and/or with a dry type solvent. a. Place the airplane on jacks. (Ref~r to Jacking. Paragraph 2-12.) b. Place a pan under the gear to catch spillage . ~. At the filler plug. relieve air pressure from the strut housing chamber by removing the cap from the air valve and depressing the valve core. d. There are two methods by which the strut chamber may be filled ancllhese are as tollows: First ~Iethod: I. Remove the valve core from the filler plug at the top of ~he nose gear strut housing or at the top inboard side of the main gear housing. Allow the filler plu~ CD rem:Jin installed. :!. .-\ [[3ch one end of a clean plastic hose to the valve stem of the filler pi u~ and ~ubm erge the other end in a container of hydraulic fluid. NOTE .-\n air-tight connection is necessary between the plas- tic rube and the valve stem. Without such a connecrton. a :5 mall amount of air will be sucked into the oleo strut during each :sequence. resulting in an inordinate amount ot air bubbles and a prolonged filling operation . HANDLI~ .-\l'-.1J SERVlCI:\G Issued: 12(29(:"2 le8 r-( PIPER TWIN COMANCHE SERVICE MANUAL -----------:....-_-----.3. Fully compress and extend the strut thus drawing nuid from the tluid containl:r and expelling air from IhI: strut chambl:r. By watching the nuid pass through the plaslic hose. it C,IO be dl:tl:rmined when lhe slrut is full and no air is present in the chamber. 4. When air bubbles cease to now through Ihe hose. compress the strut fully and rl:nlllVI: Ihe hose from the valve stem. 5. With the strut compressed. remove the filler plug to determine that the tluid k"d is visibk up 10 the bOllom of the filler hole:. 6. Reinstall the core in the filler plug and the plug in the strut housing and tighlen. Second Method: I. Remove the filler plug from the top of the nose gear strut housing or at the top inboard side of the main gear housing. 2. Raise the strut piston tube until it is fully compressed. 3. Pour tluid from a clean container through the filler opening until it reaches the bOllom of the filler plug hole. (Air pressure type oil container may be helpful.) 4. Install the filler plug finger tight, and extend and compress the strut two or three limes to remove air from the housing. 5. Remove the filler plug. raise the strut to full compression and fill with fluid if needed. 6. Reinstall fill plug and tighten. e. With the airplane raised. retract and extend the gear strut several times to asccrtain Ihal the sHul actuates freely. The weight of the gear fork and wheel should extend the strut. f. Clean off overtlow of tluid and inflate the strut as described in paragraph 2-36. g. Check that tluid is not leaking around the strut piston at the bOllom of the housing. 2-36. INFLATING OLEO STRUTS. After making certain that an oleo strut has sufficient Iluid alia., strut pump to the air valve and intlate the oleo strut. The main gear struts should be intlated 10 provide e extension with normal static load (empty weight plug full fuel and oil) of a recommended 2.75 im:hcs of pislon exposure, although it may be reduced to 2.25 inches at the pilot's discretion. (The nose ge,lr slrut may vary from 2.25 to 2.75 inches.) (Refer to Paragraph 2-34.) Rock the airplane several times to ascertain Ih,lllhe gea r settles back to the correct strut position. (If a strut pump is not available. the airplane may be raised and line pressure from a high pressure air system used. Lower the airplane and while rocking it, let air from the valvc 10 bring the strut down to' the proper extension.) Before capping th"e valve, check for valve core leakage; •Issued: 12/29/72 lC9 HANDLING AND SERVICING • '. PIPER TWIN COMANCHE SERVICE MA NUAL 1-3;. BRAKE SYSTEM. 1-38. SERVICING BRAKE SYSTEM. The brake system incorporates a hydraulic fluid reservoir through which the brake system is periodically serviced. Fluid is drawn from the reservoir by the brake cylinders to maintain the volume of tluid required for maximum braking efficiency. Spongy brake pedal action is often an indication that the brake fluid reservoir is running low on fluid or air in the system. Instt'Ucdons for filling the reservoir are given in paragraph 2-39. When found necessary to accomplish repairs to any of the brake.system compon- ents, or to bleed the system, these instructions may be found in Section vn. 2-39. FILLING BRAKE CYLINDER RESERVOIR. The brake cylinder reservoir should be fUled to rhe level marked on reservoir, With the fluid specified in Table II-I. The reservoir, located on the left side of the forward cabin bulkhead in the nose section (refer to Figure 2-15 or 2-16), should be checked at every lOO-hour inspection and replenished as necessary. No adjustment of the brakes is necessary, though they should be checked periodically per instt'Uctions given in Section VU. 2-40. DR.-\INING BRAKE SYSTEM. To drain the. brake system, connect a hose to the bleeder fitting on the bottom of the cylinder and place the other end of the line in a suitable container. Open the bleeder and slowly pump the desired brake pedal until tluid ceases to flow. To clean the brake system, flush with denatured alcohol. 2 - 41. TIR ES . 2-011. SERVICI~G TIRES. Thetires should be maintained at the pressure spec- ified in Table II-I. When checking tire pressure, examine the tire for wear, cuts, bruises and slippage. HANDLING Ar--'D SERVICING Issued: 111':'9/7: lClO 1851 PIPER TWIN COMA NCHE SER VICE MA NUA L • ..".-.. 11 • 1. BATTERY 2. FILLER OXYGEN 3. RJEL SELECTOR VALVES AND DRAINS 4. FILLER. MAIN FUEL CELL S. FILLER. MAIN OLEO SHOCK STRUT L AND R e. FILTER. VACUUM REGULATOR 7. FILLER. AUXILIARY FUEL CELL 8. nRE. MAIN GEAR L AND R 9. ENGINE OIL SUcnON SCREEN 10. RJEL INJECTOR 11. AIR VALVE. PROPELLER 12. FILTER. ENGINE OIL 13. FILLER. ENGINE OIL 14. FILTER. ENGINE AIR INTAKE 1S. nRE. NOSE GEAR le. VACUUM SYSTEM CENTRAL AIR FILTER 17. 8RAKE FLUID RESERVOIR 18. FILLER. NOSE OLEO SHOCK STRUT Figure 2-15. Service Points Serial :'-Jos. 30-1 to 30-852 incl. and 30-854 to 30-90l in~l. lell • • • PIPER TWIN COMANCHE SERVICE ~lANUAL .1921 1. FILLER OXYGEN 2. RJEL SELECTOR VALVES. AND DRAINS 3. FILLER. MAIN FUEL CELL 4. FILLER. MAIN OLEO SHOCK STRUT L AND R 5. FILTER. VACUUM REGULATOR 8. FILLER. AUXIUARY FUEL c.:El:L 7. TIRE. MAIN GEAR LAND R 8. ENGINE OIL SUCT10N SCREEN 9. RJEL INJECTOR 10. AIR VALVE. PROPELLER 11. FILTER. ENGINE OIL 12. FILLER. ENGINE OIL 13. FILTER. ENGINE AIR INTAKE 14. BATTERY 15. TIRE. NOSE GEAR 18. FILLER NOSE OLEO SHOCK STRUT 17. 8RAKE FLUID RESERVOIR 18. VACUUM SYSTEM CENTRAL AIR FlYER • Figure 2-10. Service Points Seri:1 1 ~os. 30-853, 30-902 to 30-2000 inclusive HA~DLI:-':G .~:-"L' SERVICI).;·G lssu~d: 1:::9'7: Jel2 ,r-' PIPER TWIN COMANCHE SERVICE MANUAL 243. POWER PLANT. ~44. SERVICING POWER PLANT. Regularly check the engine companment for oil and fuel leaks, charmg of lines, loose wires and tightness of all parts. For cle:ming of the engine compartment, refer to paragraph 2-23. Maintenance instructions for the Power Plant may be found in Sections VIII and VIllA of this manual and in the appropriate manufacturer's manualS. ;Z4S. PROPELLER. 246. SERVICING PROPELLER. The propeller blades, spinner and visible hub surfaces should be cle:med and inspected frequently for damage, cracks and oil leakage. Nicks should be removed from the leading edge of the blades in accordance with applicable FAA regulations or instructions found in Sections VIII and VlIIA. The face of each blade should be painted when necessary with a flat paint to retard glare. To prevent corrosion, wipe surfaces with a light oil or wax. The blades should be checked that they tum freely on the hub pilot tube by rocking the blades back and forth through the slight freedom allowed by the pitch change mechanism. Lubricate the propeller at 100 hour intervals in accordance with the Lubrication Chart, Figure 2·20. Ascertain propeller is chal1ed to the proper chamber pressure. Additional service information for the propeller may be found in Sections VIII and VillA. 247. POWER PLANT INDUCTION AIR FILTER. 248. REMOVAL OF AIR FILTER. a. Remove the right side access panel from the e'ngine" nacelle to glin access to the air mter box. b. Tum the three studs and remove the air ruter box cover. c. Lift the air ruter from the ruter box. 1-49. CLEANING INDUCTION AIR FILTER. a. Tap mter gently to remove dirt i'articles. Do not use compressed air or cleaning solvents. b. Inspect filter. If paper element is tom or ruptured or gasket is damaged. the tilter should be replaced. The usable life of the mter should be restricted to one year or 500 hours. whichever comes first. ' . HANDLING AND SERVICING Issued: I :r~9/n lel3 • • • • • • PIPER TWIN COMANCHE SERVICE MANUAL ~·50. CLEANING INDUCTION AIR FILTER. TURBOCHARGED. 3. C1e3n01ir nIter thoroughly with 01 dry type solvent or kerosene. b. Inspect filter. If element is punctured or nlptured or gasket is dill1101ged. the filter should be replaced. c. Allow filter to dry thoroughly then dip in SAE I0 weight oil and allow to drdin for four hours. d. Wipe off excess oil prior to installation. ~-Sl. INSTALLATION OF INDUCTION AIR FILTER. 01. Place falter in air box and install cover. b. Secure cover by turning studs. On turbocharged airplanes, secure air box. cover with wing nuts and safety. HANDLI~ AND SERVICING . Issued: 12/29/72 lC14 - - PIPER TWIN COMANCHE SERVICE MANUAL • 2-52. VACUUM SYSTEM AIR FILTERS. 2-53. REPLACEME~T OF CENTRAL AIR FILTER. Each 100 hours of operation the central air filter. located just forward of the forward cabin bulkhead. should be replaced. a. Remove top nose access panel by loosening quaner tum fasteners. b. Remove vacuum hoses from filter by removing spring clamps. c. Remove nut from stud attaching filter to mounting bracket. . d. Install new filter in reverse order of removal. 2-S4. REPLACEMENT OF INSTRUMENT AIR FILTER. Remove the filter assembly and replace during the SOO hour inspection of the airplane. a. Remove screws attaching air inlet plate to back of instrument. b. Remove snap ring that holds the filter in place and remove filter. c. Install new filter in adapter and secure with snap ring. d. Install air inlet plate to back of instrument and secure with screws. 2-55. REPLACEMENT OF VACUUM REGULATOR FILTERS. Every 100 hours of operation the regulator filters. located aft of tbe firewall in each engine nacelle. should be replaced. a. Remove top access panel from each engine nacelle. b. Remove filter from around the regulator and replace with new one. c. Install top naceUe access panels and secure with screws. • 2-S6. FUEL SYSTEMS. 2-S7. SERVICING FUEL SYSTEM. At intervals of SO hours or 90 days. whichever comes first. clean tbe screen ~n each filter bowl located through an access opening in the center boltom of the fuselage. Remove and clean the screens in accordanc~ with instructions outlined in Section IX. Inspection intervals of the various fuel system components may be found in Section Ill. Also. check condition of gaskets and seals at all filler openinss. and ensure that filler cap rubber is in good condition. Check to see that the filler cap fits snugly in the opening when in the locked position. 2-58. FILLING FUEL CELLS. Observe all required precautions for hanuling gasoline. FUl the fuel cells to the bottom of the flller neck with the fuel spf:dfit:u on the placard located on the underside of the filler cover ur in Table U- I. Ea~h main (inboard) fuel cell holds a maximum of 30 U. S. gallons. The auxilia ry (outboard) fuel cells have a maximum capacity of 15 U. S . gallons each whkh give a toral ot 90 L!. S. gallons of fuel with 84 U. S. gallons usable. In addition. as optional equipment are tip tanks with a capaCity of 15 U. S. gallons each. In order to obtain maximum capacity when fillingiuel cells, the plane should be approximately level. • HA~DLl~G A:'lD SERVICI~G Revised: 9/ 10/79 leiS ••• • PIPER TWIN COMANCHE SERVICE MANUAL NOTE Refuel after each night to keep condensation in fuel tanks at a minimum. 2-59. DRAINING FUEL VALVES AND LINES. The fuel filter bowls and lines are drained by opening the access door within the fuselage just aft of the fuel selector console. and pulling up on the red knob in the center of each valve. A transparent plastic tube is attached to each filter bowl and extends through a hole in the bottom of the fuselage. Flow of the fuel is observed by means of the transparent tube. The fuel valves. bowls and lines should be drained regularly to check for water or dirt accumulations. NOTE To ensure removing any water that may be in the fuel lines. drain at least Y2 pint from each tank. Collect the fuel samples in a glass container so the presence of water may be observed. a. To drain the lines froni the main and auxiliary cells. open the drain valve with the selector handle on the main. Completely drain the sediment bowl before moving the selector handle to the auxiliary cell. Repeat the process for the opposite tank. b. To drain the lines frotn the tip tanks. move the fuelselector handle to the auxiliary fuel cell position; turn the master switch on~ and the electrical selector switch, located on the forward side of the selector panel. to the tip tank position. Open the drain valve to allow the line to drain. Repeat the process for the opposite tank . CAUTION During cold weather operation, if the sediment bowls drain slower than normal, or not at aU, ifcouldbe an indication of ice at the drain and the aircraft should be hangered to thaw out and drained thoroughly. 2-60. DRAINING FUEL SYSTEM. The bulk of the fuel may be drained from the fuel cells and tip tanks by the use of a siphon hose placed in the cell or tank through the filler neck. In addition. the tip tank may be drained by inserting a dowel in the plug at the bottom,of the tank and pushing up or by removing the plug itself. The remainder of the fuel may be drained by opening the drain valve in each fuel selector bowl. • Revised: 9/20/79 lC16 HANDLING AND SERVICING ".-- I PIPER TWIN COMANCHE SERVICE ~IA:-SL:AL 1~ I. ELECTRICAL SYSTEM. 1-61. SERVICING ELEcrRICAL SYSTEM. Servicing the ek..:trkal system inv()lvc~ adding distilled water to the battery to maintain correct electrolyte level. and cheddn~ cable connections and for any spilled electrolyte that would lead to ..:orrosion. Tht: se\;urity of all electrical connections should be checked as wl:lI as the opt:ration of alllight~. general condition of the generator or alternator and starter. All electrkal wires "hould be inspected for chating and bare wires. For detailed infonnation on this system. refer to Section Xl uf this man1.131. 2-63. OXYGEN SYSTEM. 2-64. SERVICING THE OXYGEN SYSTEM. Oxygen for the breathing system is furnished from a stationary cylinder located aft of the baggage area on the left side of the fuselage at station 175.0. At 1800 psi of pressure, the oxygen cylinder has a capacity of63.7 cubic feet. The cylinder valve is equipped with a hex-eapped safety device. should the cylinder become exposed to rue or extreme heat. Do not attempt to remove this device. Kc:ep the cylinder valve closed when the airplane is on the ground or when in night and the oxygen system is not being used. To open the oxygen valve, pull out on the control knob located on the instrument panel. To close the valve, push in on the control knob. Refer to Section XIV of this manual for complete service information of this system. 2-65. OXYGEN SYSTEM SAFETY PRECAUTIONS. The utmost care must be exercised in servicing. h~dling and inspection of the oxygen system. Comply with the following precautions: . a. Keep the oxygen regulators. cylinders, gauges. valves. fittings. masks and all other components of the oxygen system free of oil. grease; gasoline and all other readily combustible substances. . b. Do not allow foreign matter to enter the oxygen lines. WARNING The presence of foreign matter in the high pressure lines can C:luse an explosion. When coming in contact with oxygen equipment. keep hands. tools and clothing clean· hospital clean. c. Never attempt to repair or repaint oxygen equipment. d. Keep fire and heat away from oxygen equipment. Do not smoke while working with or near oxygen equipment. and take care not to generate sparks with carelessly handled tools when working on the oxygen system. e. Never allow electrical equipment to come in contact with the oxygen cylinder. HA ~TI LING ANO SER VlClNG Revised: 1/31/74 leI' • • • • • • PIPER TWIN COMANCHE SERVICE MANUAL f. Use Ribbon Dope Thread Sealant (PermaceI412) on male ends of fittings only. Wrap thread in direction of thread spiral. beginning with the second thread on the fitting. Avoid getting any sealant into the lines. 2-66. FILLING OXYGEN CYLINDER. The filler valve for the oxygen system is accessible through a door located on the left side of the fuselage just aft' of the rear window. a. To fill the oxygen cyilnder, open the access door; remove the cap from the filler valve and attach the filler hose from the oxygen recharge unit to the filler valve. Ascertain that all fittings are free from oil, grease, dirt, etc. NOTE If the airplane's oxygen cylinder pressure is below 50 psi, the system should be purged as described in Section XIV. b. To obtain the correct filling pressure for the oxygen system at various ambient temperatures, a table is included for your convenience. The pressures given are not exact, but sufficiently accurate for practical purposes of working pressures between 1800 and 2400 psig cylinders. The cylinder should be allowed to cool to a stabilized temperature after filling before checking against the figures given in Table II-lIlA. c. When using a recharge u~it consisting of one supply cylinder, slowly open the valve of the supply unit and allow the oxygen to transfer. d. When using a recharge unit consisting of two or more supply cylinders (cascade storage system), it is re,commended that the following procedure be used: I. Before opening any valves, check the pressure remaining in the airplane's oxygen cylinder. If it ,is still partly charged, note the pressure indicated on the cylinder gauge. Then open and close each valve on the cascade storage system and determine which cylinder has the lowest pressure. When found, if this cylinder has a pressure lower than the oxygen cylinder in the airplane, do not attempt using it for filling. Use the storage cylinder that has a pressure higher than the airplane's cylinder but lower than the others. 2. Open the valve on only the one 'storage cylinder with the loweest pressure. When the pressure indicated on the airplane's oxygen gauge and charging gauge has become equal, close the valve of the storage cylinder, then go to the storage cylinder with the next higher pressure and repeat the procedure. 3. If, after using the last storage cylinder, the airplane's oxygen system is still not fully charged, a full storage cylinder should be put in place of a cylinder'with the Jowest pressure and used in the same manner. . 4. A good deal of oxygen will remain in the large cylinders used in the cascade system after filling only one of the cylinders, but such remaining oxygen will be at a pressure something less than the 1800 pounds, which is not sufficient pressure to completely refill another aircraft cylinder, although it will refill several small cylinders. S. It is not economical, even on a three or four-cylinder cascade system, to begin recharging with oxygen at less than 300 psi pressure in the 300 cubic foot bank of cylinders. So, use 300 cubic foot cylinders down to approximately 300 psi, then return for refilling. In two-cylinder systems, use to approximately 600 psi, then return for filling. e. When the pressure gauge on the recharge unit or in the airplane reaches 1800 psi. close the pressure regulator valve on the recharge unit. Disconnect the filler hose from the filler valve; replace the protective cap on the filler valve and close the access cover. Check the cylinder pressure according to Table II-lIlA after the cylinder temperature stabilizes. Revised: 1/31/74 leIs HANDLING AND SERVICING r r PIPER TWIN COMANCHE SERVICE MAt'l1.!.~L TABLE II-OIA. INDICATED OXYGEN PRESSURES FOR GIVEN AMBIENT TEMPERATURES Tl:mp~rature 0 F Indicated Cylinder Pressure (psig) 110 1980 100 1935 90 1890 ·80 " 1845 70 1800 60 1755 50 1710 40 1665 1-67. LUBRICATION. 1-68. OIL SYSTEMS (ENGINE). 1-69. SERVICING OIL SYSTEM. The enline oil level should be checked before eac"h night and changed after each 50 houn of engine operation. During oil change, the oil screen(s) should be removed and cleaned and, when installed, Jhe oil mter cartridge replaced. Intl:rvals between oil changes can be increased as much as 100% on enginl:s e4uipped with iull Ilow (cartridge type) oil filters provided the element is replaced each 50 hours of op~iJtion. Removal and cleaning of screens may be found in paragraphs 1·7'1 and 2-73. The ~ngine manufacturer does not recommend oils by brand names. Use a quality brand Aviation Grade Oil of the proper season viscosity. For infonnation on the use of dctcrl!l:nt oil, refer to paragraph 2-76 and/ or the latest revision of Lycoming Service Instruction Letter 1014. CAUfION Do not inuoduceany trade additive to the basic lubricant unless recommended by the engine manufacturer. H.-\~DLlNG .,Hm SERVICI~ Revised: 6/4/81 lC19 • • ACCESSORY HOUSIHG • PIPER TWIN COMANCHE SERVICE MANUAL 2-70. DRAINING OIL SUMP. To drain oil sump, provide a suitable container with a minimum capacity of 8 quarts . a. Remove the oil drain access plate from bottom of the engine cowl. b. Remove oil drain plug from bottom ofthe engine sump. It is recommended the engine be warmed to operating temperature to insure complete draining of the old oil. • Figure 2-17. Oil Suction Screen Figure 2-18. Oil Pressure Screen . .1 2-71. FULLING OIL SUMP. The oil sump should normaUy be filled withoiltothe8 U.S. quart mark on the engine dipstick. The specified grade of oil may be found in Table II-V, the Lubrication Chart, or on each engine oil filler access door. To service the engine with oil, open the quick release access door on the left side of each engine cowling and remove the oil filler cap with dipstick. 2-72. OIL SCREEN (SUCTION). The suction screen located in the bottom of the sump to the right of the air induction inlet should be cleaned at each oil change to remove any accumulation of sludge and to examine for metal filings or chips. If metal particles are found in the screen, the engine should be examined for internal damage. The suction screen is removed from the sump by cutting the safety wire and removing the hex head plug. Clean and inspect the screen and gasket and replace the gasket if over compressed or damaged. To eliminate damage to the oil screen, place it inside the recess in the hex head plug before inserting the Issued: 12/29/71 lC20 0. HANDL