AD 46-23-06

final rule

Airworthiness Directives; Noorduyn Models Army UC-64, -64A, and -64B Airplanes

AD Number
46-23-06
Status
final_rule
Effective Date
Product Category
aircraft
Docket
Unknown
FR Citation
This information is not available.
Technical illustration of an aircraft fuel pump, filter, valve, and lines
Problem area Fuel system

Applicability

TypeManufacturerModelDetails
aircraft Noorduyn Aviation Ltd. Army UC-64 Airworthiness Directives; Noorduyn Models Army UC-64, -64A, and -64B Airplanes
aircraft Noorduyn Aviation Ltd. Army UC-64A Airworthiness Directives; Noorduyn Models Army UC-64, -64A, and -64B Airplanes
aircraft Noorduyn Aviation Ltd. Army UC-64B Airworthiness Directives; Noorduyn Models Army UC-64, -64A, and -64B Airplanes

Unsafe Condition

The surface combustion fuel burning heater may allow flames or hot gases to contact the belly fuel tank, leading to fuel tank ignition or structural failure.

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

Required Actions

Disconnect and plug the fuel line as near the engine as practicable, or install a fire-resistant bulkhead between the heater and belly fuel tank, a pilot-accessible fuel shutoff valve in the fuel line, and shrouds on the heater exhaust and drain lines.

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

Compliance Time

next periodic inspection

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

Affected Aircraft

Noorduyn Models Army UC-64, -64A, and -64B airplanes equipped with surface combustion fuel-burning cabin heaters.

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

Federal Register Abstract

Surface Combustion Fuel Burning Heater

Applicability Source Text

Show captured applicability text from the source AD
AD Final Rules - DRS_46-23-06.html
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Details
AD Number:
46-23-06
Document Type:
AD Final Rules
Docket Number:
Unknown
Subject Heading:
Airworthiness Directives; Noorduyn Models Army UC-64, -64A, and -64B Airplanes
Subject:
Surface Combustion Fuel Burning Heater
Status:
Current
Citation:
This information is not available.
Citation Publish Date:
Effective Date:
Make:
Noorduyn Aviation Ltd.
Model:
Army UC-64 | Army UC-64A | Army UC-64B
Product Type:
Aircraft
Product Subtype:
Small 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Superseded AD: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: 46-23-06
CITATION:   This information is not available.

PAGE NUMBER:  

DOCKET NUMBER:   Unknown

AMENDMENT:  

AD NUMBER:   46-23-06

SUBJECT HEADING:   Airworthiness Directives; Noorduyn Models Army UC-64, -64A, and -64B Airplanes

ACTION:  

SUMMARY:  

DATES:  

ADDRESSES:  

FOR FURTHER INFORMATION CONTACT:  

SUPPLEMENTARY INFORMATION:  

REGULATORY TEXT:   46-23-06 NOORDUYN: (Was Mandatory Note 2 of AD-2-578-1.) Applies Only to Army UC-64, -64A, and -64B Airplanes Equipped With Fuel-Burning Cabin Heaters.
Required at next periodic inspection.
The surface combustion fuel burning heater must be made inoperative by disconnecting and plugging the fuel line as near the engine as practicable unless the following modifications are accomplished:
(a) At fire resistant bulkhead must be installed between the heater and the belly fuel tank. A firewall having the fire-resistant qualities specified in CAR 3.624 will be acceptable.
(b) A fuel shutoff valve, controllable from the pilots' compartment must be installed in the fuel line between the engine and the heater.
(c) Shrouds must be installed on the heater exhaust and drain lines to isolate the lines from the airframe.

FOOTER:

Document Text

Show stored source text (verify against official source)
AD Final Rules - DRS_46-23-06.html
Copy URL
Print/Save as PDF
Document Versions
 Feedback
Details
AD Number:
46-23-06
Document Type:
AD Final Rules
Docket Number:
Unknown
Subject Heading:
Airworthiness Directives; Noorduyn Models Army UC-64, -64A, and -64B Airplanes
Subject:
Surface Combustion Fuel Burning Heater
Status:
Current
Citation:
This information is not available.
Citation Publish Date:
Effective Date:
Make:
Noorduyn Aviation Ltd.
Model:
Army UC-64 | Army UC-64A | Army UC-64B
Product Type:
Aircraft
Product Subtype:
Small 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: 46-23-06
CITATION:   This information is not available.

PAGE NUMBER:  

DOCKET NUMBER:   Unknown

AMENDMENT:  

AD NUMBER:   46-23-06

SUBJECT HEADING:   Airworthiness Directives; Noorduyn Models Army UC-64, -64A, and -64B Airplanes

ACTION:  

SUMMARY:  

DATES:  

ADDRESSES:  

FOR FURTHER INFORMATION CONTACT:  

SUPPLEMENTARY INFORMATION:  

REGULATORY TEXT:   46-23-06 NOORDUYN: (Was Mandatory Note 2 of AD-2-578-1.) Applies Only to Army UC-64, -64A, and -64B Airplanes Equipped With Fuel-Burning Cabin Heaters.
Required at next periodic inspection.
The surface combustion fuel burning heater must be made inoperative by disconnecting and plugging the fuel line as near the engine as practicable unless the following modifications are accomplished:
(a) At fire resistant bulkhead must be installed between the heater and the belly fuel tank. A firewall having the fire-resistant qualities specified in CAR 3.624 will be acceptable.
(b) A fuel shutoff valve, controllable from the pilots' compartment must be installed in the fuel line between the engine and the heater.
(c) Shrouds must be installed on the heater exhaust and drain lines to isolate the lines from the airframe.

FOOTER:

Source: Official FAA Source ↗

Retrieved: Apr 8, 2026

Rights: U.S. Government Public Domain

This site is not affiliated with or endorsed by the FAA. Always verify with official sources.