48-10-01 DOUGLAS: Applies to DC-6 Aircraft. \n\n\tTo be accomplished prior to return to service in class A operation-with cabin supercharging and thermal deicing operative (with the exception of heat windshield deicing) and with cabin heaters inoperative. \n\n\tRework must be accomplished in accordance with the following Douglas Co. data: \n\n\tService Bulletin DC-6 No. 204A. Procedure for Disconnecting No. 2 and No. 3 Alternate Fuel Cells, dated December 18, 1947, or Service Bulletin DC-6 No. 204B, Fuel Tank Vent System Revision, as revised February 19, 1948. \n\n\tService Bulletin DC-6 No. 200, Revised Heater Fuel Pressure Regulator Diaphragms, as revised February 26, 1948. \n\n\tService Bulletin DC-6 No. 201, Removal-Heater Fuel Pressure Regulator Static Balance Lines, dated December 6, 1947. \n\n\tService Bulletin DC-6 No. 202, Heater Fuel Pump Check Valve-Rework, dated December 9, 1947. \n\n\tService Bulletin DC-6 No. 208, Cabin Heater and De-icer Fuel System Revision, as revised February 20, 1948. \n\n\tService Bulletin DC-6 No. 226, section I of V, Fire Extinguisher System for Boiler Room, as revised February 19, 1948. \n\n\tService Bulletin DC-6 No. 226, section II of V, CO2 Piping, as revised February 21, 1948. \n\n\tService Bulletin DC-6 No. 226, section III of V, Installation Fire Detector Boxes and Conduit, dated February 12, 1948. Except that fire detectors in the under floor cargo compartments are not required since these compartments have been determined to comply with CAR 4b.383(d) requirements for Class "D" compartments when they otherwise comply with this Airworthiness Directive. \n\n\tService Bulletin DC-6 No. 226, section IV of V, Electrical Rework, as revised Feb. 26, 1948. \n\n\tService Bulletin DC-6 No. 226, section V of V, Sealing of Forward and Aft Baggage Compartment and Invertor Compartment Blower Duct, as revised February 24, 1948. \n\n\tService Bulletin DC-6 No. 233, Fuel Overboard Drains for Wing Nose Area, dated January 14, 1948. \n\n\tServiceBulletin DC-6 No. 247, Drainage Holes and Dams for Fuselage and Wings, as revised February 18, 1948. \n\n\tService Bulletin DC-6 No. 252, Heater Exhaust Louver Removal, as revised February 17, 1948. \n\n\tService Bulletin DC-6 No. 262, Installation of Combustion Heater Backfire Switches dated February 24, 1948. \n\n\tSuperchargers with No. 7357594 stamped on gearbox housing and 5357091 stamped on the impeller housing (scroll) are satisfactory for A operation. These superchargers will be eligible for either A or C operation when reworked and identified as shown in Douglas Service Bulletin DC-6 No. 258. \n\n\tService Bulletin DC-6 No. 225, Alcohol Windshield De-icing System, as revised February 24, 1948. \n\n\tService Bulletin DC-6 No. 246, Relocation of Manual and Automatic Pressure Relief Valve, as revised February 17, 1948. \n\n\tService Bulletin No. 224 canceled October 4, 1961. \n\n\tService Bulletin DC-6 No. 217, Installation of Fire Axe, as revised Dec. 23, 1947. \n\n\tService BulletinDC-6 No. 214, Modification of Main Junction Box and Annex, as revised February 16, 1948. \n\n\tService Bulletin DC-6 No. 230, Rerouting of Heater Accessory Compartment Power Cables, as revised February 16, 1948. \n\n\tService Bulletin DC-6 No. 149, Fuse Protection for Flight Instrument Transformers, dated December 5, 1947. \n\n\tService Bulletin DC-6 No. 237, Addition of Fuse on Master Switch for Buffet, as revised February 21, 1948. \n\n\tService Bulletin DC-6 No. 248, Conduit Clipping to Combustible Fluid Lines, as revised February 13, 1948, and Addendum dated February 13, 1948. \n\n\tService Bulletin DC-6 No. 212, protective Shield at Forward and AFT Cargo Compartment Lights, as revised January 7, 1948. \n\n\tService Bulletin DC-6 No. 206, Rework of Battery Leads to Prevent Shorting, dated December 9, 1947. \n\n\tService Bulletin DC-6 No. 218, Addition of Phenolic Sheet Insulation to AC Circuit Breaker Guard Assembly, dated December 17, 1947. \n\n\tService Bulletin DC-6 No. 221, Revision ofHeater Fire Extinguisher Buttons, dated December 20, 1947. \n\n\tService Bulletin DC-6 No. 210, Protection for Outer Wing Booster Pump Lead-In, as revised December 22, 1947. \n\n\tService Bulletin DC-6 No. 213, Starter and Generator Power Cable in Wing, as revised December 19, 1947. \n\n\tService Bulletin DC-6 No. 242, Relocation of Tail Heater Control Can, as revised February 17, 1948. \n\n\tService Bulletin DC-6 No. 203, Hand Fire Extinguisher Support Bracket Revision, as revised February 17, 1948. \n\n\tService Bulletin DC-6 No. 260, Installation of AAL Type Master Switch Arrangement and Emergency Inverter, as revised February 24, 1948. (This installation not required on aircraft incorporating one set of vacuum operated flight instruments.) \n\n\tService Bulletin DC-6 No. 267, Installation Heater Safety Relays, dated February 27, 1948. \n\n\tService Bulletin DC-6 No. 205, Rework of DC-6 Fuel Tank and Cell Vent Chambers, as revised February 23, 1948. \n\n\tService Bulletin DC-6 No. 207, Guard for Fuel Booster Pump Switches, as revised December 19, 1947. \n\n\tService Bulletin DC-6 No. 253, Fireproofing of Wing De-icer Ducts in Nacelles, as revised February 24, 1948. \n\n\tService Bulletin DC-6 No. 219, Rework of Whittaker Firewall Shut-Off Valves, dated December 19, 1947. \n\n\tService Bulletin DC-6 No. 114, Fuel Flow Transmitter Line Replacement, dated October 29, 1947. \n\n\tService Bulletin DC-6 No. 261, Installation of Oil Separator for Vacuum Pump Drain Lines, dated February 25, 1948. \n\n\tService Bulletin DC-6 No. 249, Boiler Room Duct Revision, dated February 24, 1948. \n\n\tService Bulletin DC-6 No. 232, Wing Heater Exhaust Insulation Cover, as revised February 16, 1948. \n\n\tService Bulletin DC-6 No. 234, Tail Heater Ground Blower Check Valve Revision, as revised January 23, 1948. \n\n\tThe rework outlined in the data listed above is based upon an airplane which incorporates certain production changes. Therefore, in order to satisfactorily complete the required rework, some aircraft* must also be revised in accordance with the following: \n\n\tService Bulletin DC-6 No. 62, Rework-Cabin Pressure Control Valve Linkage, dated September 2, 1947. \n\n\tService Bulletin DC-6 No. 111, Cabin Heater Fire Extinguisher Bottle, dated October 22, 1947. (Partial accomplishment only is required, which is to include: Support No. 5333704-10, Pipe No. 5332568-518 and attaching parts.) \n\n\tService Bulletin DC-6 No. 119, Aft Baggage Compartment Smoke Detector Pick-up Pipe Revision, dated December 6, 1947. (To be accomplished only if Modification Item 59 has not been accomplished.) \n\n\tService Bulletin DC-6 No. 16, installation of Additional Dams and Drain Plug in Fuselage Bottom, dated June 26, 1947. \n\n\tService Bulletin DC-6 No. 161, Rear Lounge Hot Air Supply Duct Sound Trap Installation, dated January 30, 1948. (Need not be accomplished on Serial Nos. 42854 through 42891, 43000 through 43009, 43055, and 43061 until Service Bulletin DC-6 No. 59, Improved Aft Lounge Heating, dated September 16,1947, has been accomplished.) \n\n\tService Bulletin DC-6 No. 95, Revision-Ground Blower Duct and Check Valve and Air Duct Connection Improvement, dated October 21, 1947. (Accomplish portion covered by Service Change No. 354 and that portion of Service Change No. 358 which includes cable assemblies 1342327-502 and -504, hook No. 1342315, latch assembly 1342314, AN 960-10L, washers, AN 486-4 clevis, AN 393-11 and -13 pins, AN 380-2-2 cotters and AN 365-428 nuts.) \n\n\tIn addition to the above, the following must also be accomplished on all aircraft: \n\n\t1. Inspect the wing structure around the fuel tanks in accordance with Douglas Service Letter to all Operators dated December 29, 1947 (ref. A214TS-2521/SRD 529.37). Any damage found as a result of the inspection must be satisfactorily repaired. \n\n\t2. The Airplane Flight Manual for each airplane must be revised to include FAA-approved procedures covering "Fuel Usage," "Fire Fighting" and "SmokeEvacuation from the Cockpit." This information, pages 1 and 2 of Section I, and pages 31 through 65 of Section III, as revised February 26, 1948, for aircraft incorporating Hamilton Standard Propellers, or pages 1 and 2 of Section I, and pages 31 through 71 of Section III, as revised February 26, 1948, for aircraft incorporating Curtiss Propellers, should be obtained from the Douglas Co. \n\n\t3. Disconnect the cabin heater electrically and block off all fuel lines to this heater. \n\n\tRevised October 4, 1961. \n\n\t*Serial numbers of airplanes affected by this rework are listed on the pertinent Service Bulletin(s). Also, additional information may be obtained from the "Supplement" to "Cross Reference List-Service Changes and Modification Items" which has been prepared and revised by the Douglas Co. as of February 11 1948.