AD 52-20-01
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | The Boeing Company | DC-6 | Airworthiness Directives; DOUGLAS Models DC-6, DC-6A, DC-6B Aircraft |
| aircraft | The Boeing Company | DC-6A | Airworthiness Directives; DOUGLAS Models DC-6, DC-6A, DC-6B Aircraft |
| aircraft | The Boeing Company | DC-6B | Airworthiness Directives; DOUGLAS Models DC-6, DC-6A, DC-6B Aircraft |
Unsafe Condition
Overvoltage in the Eclipse Generator System and General Electrical Generator System could lead to electrical fire and loss of essential electrical and electronic equipment necessary for continued flight.
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Required Actions
Replace B-14 generator contactors with 120-volt rated high-voltage contactors in the Eclipse system. Install overvoltage relays and either replace G.E. P/N 3GTR-77A102 relays with 120-volt rated relays or rework G.E. P/N XRP-12 circuit breakers to trip with the generator control relay in the General Electric system.
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Compliance Time
as soon as practicable, but not later than February 1, 1954
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Affected Aircraft
Douglas Models DC-6, DC-6A, DC-6B aircraft below serial number 43274
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Federal Register Abstract
Overvoltage Protection
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_52-20-01.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 52-20-01 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; DOUGLAS Models DC-6, DC-6A, DC-6B Aircraft Subject: Overvoltage Protection 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The Boeing Company Model: DC-6 | DC-6A | DC-6B Product Type: Aircraft Product Subtype: Large Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 52-20-01 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 52-20-01 SUBJECT HEADING: Airworthiness Directives; DOUGLAS Models DC-6, DC-6A, DC-6B Aircraft ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 52-20-01 DOUGLAS: Applies to Models DC-6, DC-6A, DC-6B Aircraft Below Serial Number 43274. To be accomplished as soon as practicable, but not later than February 1, 1954. To reduce the likelihood of electrical fire and the loss of electrical and electronic equipment essential to continue flight, it is necessary to provide adequate overvoltage protection. There are two systems involved, known as the "Eclipse Generator System" and the "General Electrical Generator System". The changes required in each of these systems are as follows: Eclipse. Replace the four B-14 type generator contactors with a high-voltage (120-volt rating) contactors of sufficient capacity to interrupt an overvoltage generator. Overvoltage relays are already installed in the Eclipse system, and these should be retained. General Electric. Install overvoltage sensing relays and either (1) replace the four generator control relays, G.E. P/N 3GTR-77A102, with a high-voltage (120-volt rating) relay of sufficient capacity to interrupt an overvoltage generator, or (2) rework the G.E. P/N XRP-12 reverses current circuit breakers so as to trip out simultaneously with the generator control relay to provide for necessary additional interruption capacity. Except for the General Electric alternate (2) fix, this same subject is described in Douglas Service Bulletin DC-6 No. 470. The General Electric Co. has service information available for the G.E. system alternate (2) rework. FOOTER:
Document Text
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AD Final Rules - DRS_52-20-01.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 52-20-01 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; DOUGLAS Models DC-6, DC-6A, DC-6B Aircraft Subject: Overvoltage Protection 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: 52-20-01 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 52-20-01 SUBJECT HEADING: Airworthiness Directives; DOUGLAS Models DC-6, DC-6A, DC-6B Aircraft ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 52-20-01 DOUGLAS: Applies to Models DC-6, DC-6A, DC-6B Aircraft Below Serial Number 43274. To be accomplished as soon as practicable, but not later than February 1, 1954. To reduce the likelihood of electrical fire and the loss of electrical and electronic equipment essential to continue flight, it is necessary to provide adequate overvoltage protection. There are two systems involved, known as the "Eclipse Generator System" and the "General Electrical Generator System". The changes required in each of these systems are as follows: Eclipse. Replace the four B-14 type generator contactors with a high-voltage (120-volt rating) contactors of sufficient capacity to interrupt an overvoltage generator. Overvoltage relays are already installed in the Eclipse system, and these should be retained. General Electric. Install overvoltage sensing relays and either (1) replace the four generator control relays, G.E. P/N 3GTR-77A102, with a high-voltage (120-volt rating) relay of sufficient capacity to interrupt an overvoltage generator, or (2) rework the G.E. P/N XRP-12 reverses current circuit breakers so as to trip out simultaneously with the generator control relay to provide for necessary additional interruption capacity. Except for the General Electric alternate (2) fix, this same subject is described in Douglas Service Bulletin DC-6 No. 470. The General Electric Co. has service information available for the G.E. system alternate (2) rework. FOOTER:
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