AD 48-51-01
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Textron Aviation Inc. | Army AT-11 | Airworthiness Directives; Beech Model AT-11, C18S, D17S Airplanes |
| aircraft | Textron Aviation Inc. | C18S | Airworthiness Directives; Beech Model AT-11, C18S, D17S Airplanes |
| aircraft | Textron Aviation Inc. | D17S | Airworthiness Directives; Beech Model AT-11, C18S, D17S Airplanes |
Unsafe Condition
Failure of the control column wheel shaft due to excessive counterbore depth in the shaft.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Drill a 3/8-inch hole in the hub center, measure counterbore depth using a scale or wire, and replace the shaft if the depth exceeds 1 7/16 inches. Ensure the drill does not penetrate more than 1 inch to avoid damaging the securing pin.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
As soon as possible, but not later than March 1, 1949.
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
Beech Model AT-11, C18S, D17S airplanes equipped with Beech Half-Circle Type control wheels.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Control Wheel Shaft Inspection
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_48-51-01.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 48-51-01 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Beech Model AT-11, C18S, D17S Airplanes Subject: Control Wheel Shaft Inspection Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: Make: Textron Aviation Inc. Model: Army AT-11 | C18S | D17S Product Type: Aircraft Product Subtype: Small Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 48-51-01 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 48-51-01 SUBJECT HEADING: Airworthiness Directives; Beech Model AT-11, C18S, D17S Airplanes ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 48-51-01 BEECH: Applies to AT-11, C18S, D17S Airplanes Equipped With Beech Half-Circle Type Control Wheels. To be accomplished as soon as possible, but not later than March 1, 1949. To preclude the possibility of failure of the control column wheel shaft due to too great a counterbore depth in the shaft, the following inspection should be accomplished: (Bow-tie type control wheels attached to the control shaft by three bolts through a flange on the shaft are satisfactory and need not be inspected). (1) Drill a 3/8-inch hole in the center of the hub of the control wheels. Do not allow the drill to go more than 1 inch into the hub or the pin securing the wheel will be damaged. (2) Place a narrow scale or straight wire through the 3/8-inch hole and obtain the distance from the bottom of the counterbore (not the peak of the counterbore cone) to the face of the hub. (3) Insert a small hook scale or bent wire in the hole and obtain the distance from the end of the shaft to the face of the hub. (4) Subtract the distance obtained in step No. 3 from the distance obtained in step No. 2 to obtain the depth of the counterbore in the end of the shaft. If this distance is over 1 7/16 inches, the shaft must be replaced. All shafts having a counterbore less than 1 7/16 inches deep are satisfactory. (Beech Service Bulletin No. C-18-9 dated November 22, 1948, covers this same subject.) FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_48-51-01.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 48-51-01 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Beech Model AT-11, C18S, D17S Airplanes Subject: Control Wheel Shaft Inspection Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: Make: Textron Aviation Inc. Model: Army AT-11 | C18S | D17S 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: 48-51-01 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 48-51-01 SUBJECT HEADING: Airworthiness Directives; Beech Model AT-11, C18S, D17S Airplanes ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 48-51-01 BEECH: Applies to AT-11, C18S, D17S Airplanes Equipped With Beech Half-Circle Type Control Wheels. To be accomplished as soon as possible, but not later than March 1, 1949. To preclude the possibility of failure of the control column wheel shaft due to too great a counterbore depth in the shaft, the following inspection should be accomplished: (Bow-tie type control wheels attached to the control shaft by three bolts through a flange on the shaft are satisfactory and need not be inspected). (1) Drill a 3/8-inch hole in the center of the hub of the control wheels. Do not allow the drill to go more than 1 inch into the hub or the pin securing the wheel will be damaged. (2) Place a narrow scale or straight wire through the 3/8-inch hole and obtain the distance from the bottom of the counterbore (not the peak of the counterbore cone) to the face of the hub. (3) Insert a small hook scale or bent wire in the hole and obtain the distance from the end of the shaft to the face of the hub. (4) Subtract the distance obtained in step No. 3 from the distance obtained in step No. 2 to obtain the depth of the counterbore in the end of the shaft. If this distance is over 1 7/16 inches, the shaft must be replaced. All shafts having a counterbore less than 1 7/16 inches deep are satisfactory. (Beech Service Bulletin No. C-18-9 dated November 22, 1948, covers this same subject.) FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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