AD 48-11-01
final rule
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | The Boeing Company | DC-6 | Airworthiness Directives; DOUGLAS DC-6 Aircraft |
| aircraft | The Boeing Company | DC-6A | Airworthiness Directives; DOUGLAS DC-6 Aircraft |
| aircraft | The Boeing Company | DC-6B | Airworthiness Directives; DOUGLAS DC-6 Aircraft |
Unsafe Condition
The unsafe condition involves the potential failure of cabin heating and thermal deicing systems when operating in class B with cabin supercharging inoperative, which could lead to loss of heating and anti-icing functionality, increasing the risk of operational hazards.
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Required Actions
Accomplish rework per specified Douglas Service Bulletins, including disconnecting superchargers and draining/flushing the supercharger oil system. Exclude certain service bulletins (258, 225, 230) and partially accomplish others as noted.
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Compliance Time
prior to return to service in class B operation
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Affected Aircraft
Douglas DC-6, DC-6A, DC-6B aircraft with cabin supercharging inoperative, as specified in the referenced Service Bulletins and Douglas Co. data.
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Federal Register Abstract
Ungrounding Modification - Class B
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_48-11-01.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 48-11-01 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; DOUGLAS DC-6 Aircraft Subject: Ungrounding Modification - Class B Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: Make: The Boeing Company Model: DC-6 | DC-6A | DC-6B Product Type: Aircraft Product Subtype: Large Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 48-11-01 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 48-11-01 SUBJECT HEADING: Airworthiness Directives; DOUGLAS DC-6 Aircraft ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 48-11-01 DOUGLAS: Applies to DC-6 Aircraft. To be accomplished prior to return to service in class B operation-with cabin heating and thermal deicing, including windshield, operative, but with cabin supercharging inoperative. Rework must be accomplished in accordance with the following Douglas Co. data: 1. Accomplish all rework covered by data listed in Note 48-10-01 for class A operation with the exception of the rework outlined in Service Bulletins No. 258, No. 225 and No. 230. Also accomplish paragraphs 1 and 2 but do not accomplish 3 of Note 48-10-01. 2. Rework in accordance with the following must also be accomplished: Service Bulletin DC-6 No. 223, Stainless Steel Heater Discharge Ducts and Windshield Anti-Icing Ducts, as revised February 24, 1948. Service Bulletin DC-6 No. 38, Heater Fire Warning Switch-Installation of, dated October 6, 1947. Service Bulletin DC-6 No. 250, Cabin Heater Shut-Off Control, dated February 19, 1948. Service Bulletin DC-6 No. 211, Main Cabin Heater Exhaust-Revision of, as revised February 23, 1948. Service Bulletin DC-6 No. 227, Cabin Heater Scoop Segregation, as revised February 24, 1948. Service Bulletin DC-6 No. 243, Revise Cabin Heater Ignition Conduit in Boiler Room and Hell-Hole Area, as revised January 26, 1948. Service Bulletin DC-6 No. 245, Heater and Buffet Power Cable Conduit, as revised February 24, 1948. The rework outlined in the data listed above is based upon an airplane which incorporates certain production changes. Therefore, in order to satisfactorily complete the rework required, some aircraft* must also be revised in accordance with the following: Service Bulletin DC-6 No. 40, Heater Exhaust Fire Detector-Replacement of, dated September 3, 1947. (Accomplish partially*). Service Bulletin DC-6 No. 71, Installation-Oil Trap and Drain, Cabin Heater Combustion Air Duct, dated September 3, 1947. (Accomplish Electrical Phase of Service Bulletin only.) Service Bulletin DC-6 No. 96, Windshield De-icing Air Discharge Revision, dated December 22, 1947. Service Bulletin DC-6 No. 141, Improvements in DC-6 Cabin Pressure and Cabin Air Conditioning Systems, dated February 19, 1948. Service Bulletin DC-6 No. 150, Revision-Cockpit and Windshield Heat Control System and Windshield Air Exhaust, dated December 11, 1947. Service Bulletin DC-6 No. 160, Cabin Air Mixing Valve Actuator, dated February 2, 1948. Service Bulletin DC-6 No. 179, Ground Blower Electrical Wiring Revision, dated December 29, 1947. Service Bulletin DC-6 No. 28, Installation of Ammeter and Selector Switch for Functional Check of Pitot and Air Scoop Anti-Icing Heaters, dated August 20, 1947. (Must be accomplished completely except that P/N 3320167-516 nameplate, 1 required, shall be deleted.) In addition to the above, the following must also be accomplished in all aircraft: (a) Disconnect the superchargers and drain and flush supercharger oil system. *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. FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_48-11-01.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 48-11-01 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; DOUGLAS DC-6 Aircraft Subject: Ungrounding Modification - Class B Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: Make: The Boeing Company Model: DC-6 | DC-6A | DC-6B Product Type: Aircraft Product Subtype: Large Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 48-11-01 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 48-11-01 SUBJECT HEADING: Airworthiness Directives; DOUGLAS DC-6 Aircraft ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 48-11-01 DOUGLAS: Applies to DC-6 Aircraft. To be accomplished prior to return to service in class B operation-with cabin heating and thermal deicing, including windshield, operative, but with cabin supercharging inoperative. Rework must be accomplished in accordance with the following Douglas Co. data: 1. Accomplish all rework covered by data listed in Note 48-10-01 for class A operation with the exception of the rework outlined in Service Bulletins No. 258, No. 225 and No. 230. Also accomplish paragraphs 1 and 2 but do not accomplish 3 of Note 48-10-01. 2. Rework in accordance with the following must also be accomplished: Service Bulletin DC-6 No. 223, Stainless Steel Heater Discharge Ducts and Windshield Anti-Icing Ducts, as revised February 24, 1948. Service Bulletin DC-6 No. 38, Heater Fire Warning Switch-Installation of, dated October 6, 1947. Service Bulletin DC-6 No. 250, Cabin Heater Shut-Off Control, dated February 19, 1948. Service Bulletin DC-6 No. 211, Main Cabin Heater Exhaust-Revision of, as revised February 23, 1948. Service Bulletin DC-6 No. 227, Cabin Heater Scoop Segregation, as revised February 24, 1948. Service Bulletin DC-6 No. 243, Revise Cabin Heater Ignition Conduit in Boiler Room and Hell-Hole Area, as revised January 26, 1948. Service Bulletin DC-6 No. 245, Heater and Buffet Power Cable Conduit, as revised February 24, 1948. The rework outlined in the data listed above is based upon an airplane which incorporates certain production changes. Therefore, in order to satisfactorily complete the rework required, some aircraft* must also be revised in accordance with the following: Service Bulletin DC-6 No. 40, Heater Exhaust Fire Detector-Replacement of, dated September 3, 1947. (Accomplish partially*). Service Bulletin DC-6 No. 71, Installation-Oil Trap and Drain, Cabin Heater Combustion Air Duct, dated September 3, 1947. (Accomplish Electrical Phase of Service Bulletin only.) Service Bulletin DC-6 No. 96, Windshield De-icing Air Discharge Revision, dated December 22, 1947. Service Bulletin DC-6 No. 141, Improvements in DC-6 Cabin Pressure and Cabin Air Conditioning Systems, dated February 19, 1948. Service Bulletin DC-6 No. 150, Revision-Cockpit and Windshield Heat Control System and Windshield Air Exhaust, dated December 11, 1947. Service Bulletin DC-6 No. 160, Cabin Air Mixing Valve Actuator, dated February 2, 1948. Service Bulletin DC-6 No. 179, Ground Blower Electrical Wiring Revision, dated December 29, 1947. Service Bulletin DC-6 No. 28, Installation of Ammeter and Selector Switch for Functional Check of Pitot and Air Scoop Anti-Icing Heaters, dated August 20, 1947. (Must be accomplished completely except that P/N 3320167-516 nameplate, 1 required, shall be deleted.) In addition to the above, the following must also be accomplished in all aircraft: (a) Disconnect the superchargers and drain and flush supercharger oil system. *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. FOOTER:
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