AD 62-27-05

final rule

Airworthiness Directives; Fairchild Model F-27 Aircraft

AD Number
62-27-05
Status
final_rule
Effective Date
Product Category
aircraft
Docket
Unknown
FR Citation
This information is not available.

Applicability

TypeManufacturerModelDetails
aircraft Maryland Air Industries, Inc. F-27 Airworthiness Directives; Fairchild Model F-27 Aircraft
aircraft Maryland Air Industries, Inc. F-27A Airworthiness Directives; Fairchild Model F-27 Aircraft
aircraft Maryland Air Industries, Inc. F-27B Airworthiness Directives; Fairchild Model F-27 Aircraft
aircraft Maryland Air Industries, Inc. F-27F Airworthiness Directives; Fairchild Model F-27 Aircraft
aircraft Maryland Air Industries, Inc. F-27G Airworthiness Directives; Fairchild Model F-27 Aircraft
aircraft Maryland Air Industries, Inc. F-27J Airworthiness Directives; Fairchild Model F-27 Aircraft
aircraft Maryland Air Industries, Inc. F-27M Airworthiness Directives; Fairchild Model F-27 Aircraft

Unsafe Condition

Loss of DC power to the primary DC bus due to failure of the forward primary bus relay and loss of AC power to certain engine instruments due to failure of the 115/26V instrument transformer.

AI-generated summary from the source AD text. Verify against the official source before acting.

Required Actions

Install an auxiliary forward primary bus relay (Cutler Hammer P/N 6041H172) with independent control circuit including a 5-ampere circuit breaker and separate contacts in the load monitor switch (P/N MS35059-22). Install an Eclipse-Pioneer DW-73-A1 instrument transformer and selector switch (P/N MS 35059-23) to provide alternate AC power for engine instruments.

AI-generated summary from the source AD text. Verify against the official source before acting.

Compliance Time

within the next 1,000 hours' time in service after the effective date of this AD

AI-generated summary from the source AD text. Verify against the official source before acting.

Affected Aircraft

Fairchild Model F-27 Aircraft Serial Numbers 2 to 95 Inclusive

AI-generated summary from the source AD text. Verify against the official source before acting.

Federal Register Abstract

Electrical Distribution System

Applicability Source Text

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AD Number:
62-27-05
Document Type:
AD Final Rules
Docket Number:
Unknown
Subject Heading:
Airworthiness Directives; Fairchild Model F-27 Aircraft
Subject:
Electrical Distribution System
Status:
Current
Citation:
This information is not available.
Citation Publish Date:
Effective Date:
01/29/1963
Make:
Maryland Air Industries, Inc.
Model:
F-27 | F-27A | F-27B | F-27F | F-27G | F-27J | F-27M
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: 62-27-05
CITATION:   This information is not available.

PAGE NUMBER:  

DOCKET NUMBER:   Unknown

AMENDMENT:  

AD NUMBER:   62-27-05

SUBJECT HEADING:   Airworthiness Directives; Fairchild Model F-27 Aircraft

ACTION:  

SUMMARY:  

DATES:   Effective January 29, 1963.

ADDRESSES:  

FOR FURTHER INFORMATION CONTACT:  

SUPPLEMENTARY INFORMATION:  

REGULATORY TEXT:  
62-27-05 FAIRCHILD: Amdt. 524 Part 507 Federal Register December 28, 1962. Applies to Model F-27 Aircraft Serial Numbers 2 to 95 Inclusive.

Compliance required within the next 1,000 hours' time in service after the effective date of this AD.

In order to preclude the loss of DC power to the primary DC bus in the event of failure of the forward primary bus relay, and the loss of AC power to certain engine instruments in the event of loss of the 115/26V instrument transformer, the following, or an equivalent approved by Chief, Engineering and Manufacturing Branch, FAA Eastern Region, New York, shall be accomplished:

(a) Modify the DC electric distribution system to provide an alternate means of connecting the primary bus to the No. 2 electrical panel battery-generator feeder bus by installing one auxiliary forward primary bus relay, Cutler Hammer P/N 6041H172 in parallel with the existing forward primary bus relay. The control circuit for this auxiliary relay shall be made independent of the control circuit for the existing primary bus relay by connecting it to the flight emergency bus through an added 5-ampere circuit breaker and through a separate pair of contacts in the load monitor switch, P/N MS35059-22.

(b) Modify the AC electric distribution system to provide an alternate means of supplying 26V electric power to the AC engine instruments by installing one Eclipse-Pioneer instrument transformer type DW-73-A1 and one selector switch P/N MS 35059-23 which will provide for selection of either one of the two instrument transformers.

(Fairchild Service Bulletin 24-9 Revision No. 1, dated June 11, 1962, covers this same subject.)

This directive effective January 29, 1963.

FOOTER:

Document Text

Show stored source text (verify against official source)
AD Final Rules - DRS_62-27-05.html
Copy URL
Print/Save as PDF
Document Versions
 Feedback
Details
AD Number:
62-27-05
Document Type:
AD Final Rules
Docket Number:
Unknown
Subject Heading:
Airworthiness Directives; Fairchild Model F-27 Aircraft
Subject:
Electrical Distribution System
Status:
Current
Citation:
This information is not available.
Citation Publish Date:
Effective Date:
01/29/1963
Make:
Maryland Air Industries, Inc.
Model:
F-27 | F-27A | F-27B | F-27F | F-27G | F-27J | F-27M
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: 62-27-05
CITATION:   This information is not available.

PAGE NUMBER:  

DOCKET NUMBER:   Unknown

AMENDMENT:  

AD NUMBER:   62-27-05

SUBJECT HEADING:   Airworthiness Directives; Fairchild Model F-27 Aircraft

ACTION:  

SUMMARY:  

DATES:   Effective January 29, 1963.

ADDRESSES:  

FOR FURTHER INFORMATION CONTACT:  

SUPPLEMENTARY INFORMATION:  

REGULATORY TEXT:  
62-27-05 FAIRCHILD: Amdt. 524 Part 507 Federal Register December 28, 1962. Applies to Model F-27 Aircraft Serial Numbers 2 to 95 Inclusive.

Compliance required within the next 1,000 hours' time in service after the effective date of this AD.

In order to preclude the loss of DC power to the primary DC bus in the event of failure of the forward primary bus relay, and the loss of AC power to certain engine instruments in the event of loss of the 115/26V instrument transformer, the following, or an equivalent approved by Chief, Engineering and Manufacturing Branch, FAA Eastern Region, New York, shall be accomplished:

(a) Modify the DC electric distribution system to provide an alternate means of connecting the primary bus to the No. 2 electrical panel battery-generator feeder bus by installing one auxiliary forward primary bus relay, Cutler Hammer P/N 6041H172 in parallel with the existing forward primary bus relay. The control circuit for this auxiliary relay shall be made independent of the control circuit for the existing primary bus relay by connecting it to the flight emergency bus through an added 5-ampere circuit breaker and through a separate pair of contacts in the load monitor switch, P/N MS35059-22.

(b) Modify the AC electric distribution system to provide an alternate means of supplying 26V electric power to the AC engine instruments by installing one Eclipse-Pioneer instrument transformer type DW-73-A1 and one selector switch P/N MS 35059-23 which will provide for selection of either one of the two instrument transformers.

(Fairchild Service Bulletin 24-9 Revision No. 1, dated June 11, 1962, covers this same subject.)

This directive effective January 29, 1963.

FOOTER:

Source: Official FAA Source ↗

Retrieved: Apr 8, 2026

Rights: U.S. Government Public Domain

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