46-23-05: Horizontal Stabilizer Drain Holes
FAA order 46-23-05 is an airworthiness directive. The FAA's subject line: Horizontal Stabilizer Drain Holes. System: airframe structure.
What it applies to as the FAA lists it
- Kind of product
- Aircraft
- Makes
- Noorduyn Aviation Ltd.
- Models
- Army UC-64, Army UC-64A, Army UC-64B
Dates and paperwork
- Docket
- Unknown
- Status
- Current
- The FAA's document
- Read the order on the FAA's site
The order itself the regulatory text, as published
Show the full text (545 characters)
46-23-05 NOORDUYN: (Was Mandatory Note 1 of AD-2-578-1.) Applies to Army UC- 64, -64A, and -64B Aircraft.
Required at next periodic inspection.
Inspect the trailing edge of the horizontal stabilizer to determine whether or not drain holes are present in the metal trailing edge cover. If the holes are not present, it will be necessary to remove enough fabric to permit inspection of the ribs. Defective or deteriorated wood must be replaced and drain holes, approximately 1/16-inch diameter, spaced to drain all pockets must be drilled.
Source: FAA Dynamic Regulatory System, airworthiness directives. The FAA's document is the authority; the register counts are this site's, from the FAA register of November 6, 2026. Connections as data: /graph/directive/46-23-05.json · aircraft systems.