AD 46-24-01
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Boeing Airplane Company, Wichita Division | 75 (Army PT-13) | Airworthiness Directives; BOEING Model A75L3, 75, A75, B75, E75, A75J1, A75N1, B75N1, D75N1 Series Aircraft |
| aircraft | Boeing Airplane Company, Wichita Division | A75 (Army PT-13A, -13B, -13C) | Airworthiness Directives; BOEING Model A75L3, 75, A75, B75, E75, A75J1, A75N1, B75N1, D75N1 Series Aircraft |
| aircraft | Boeing Airplane Company, Wichita Division | A75J1 (Army PT-18) | Airworthiness Directives; BOEING Model A75L3, 75, A75, B75, E75, A75J1, A75N1, B75N1, D75N1 Series Aircraft |
| aircraft | Boeing Airplane Company, Wichita Division | A75L3 | Airworthiness Directives; BOEING Model A75L3, 75, A75, B75, E75, A75J1, A75N1, B75N1, D75N1 Series Aircraft |
| aircraft | Boeing Airplane Company, Wichita Division | A75N1 (Army PT-17, -17A, Navy N2S-1, -4) | Airworthiness Directives; BOEING Model A75L3, 75, A75, B75, E75, A75J1, A75N1, B75N1, D75N1 Series Aircraft |
| aircraft | Boeing Airplane Company, Wichita Division | B75 (Navy N2S-5) | Airworthiness Directives; BOEING Model A75L3, 75, A75, B75, E75, A75J1, A75N1, B75N1, D75N1 Series Aircraft |
| aircraft | Boeing Airplane Company, Wichita Division | B75N1 (Navy N2S-3) | Airworthiness Directives; BOEING Model A75L3, 75, A75, B75, E75, A75J1, A75N1, B75N1, D75N1 Series Aircraft |
| aircraft | Boeing Airplane Company, Wichita Division | D75N1 (Army PT-27) | Airworthiness Directives; BOEING Model A75L3, 75, A75, B75, E75, A75J1, A75N1, B75N1, D75N1 Series Aircraft |
| aircraft | Boeing Airplane Company, Wichita Division | E75 (Army PT-13D, Navy N2S-5, PT-13D/N2S-5) | Airworthiness Directives; BOEING Model A75L3, 75, A75, B75, E75, A75J1, A75N1, B75N1, D75N1 Series Aircraft |
Unsafe Condition
Water entrapment at the lower rear edge of the wing at the aileron gap due to inadequate drainage, leading to deterioration of rib ends.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Drill 13 No. 30 holes through fabric and dural angle at specified locations forward of the rear spar and near the 120-degree bend, using a stop to limit penetration to 1/2 inch to avoid spar damage.
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Compliance Time
next periodic inspection
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Affected Aircraft
BOEING Model A75L3, 75, A75, B75, E75, A75J1, A75N1, B75N1, D75N1 Series Aircraft
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Wing Drain Holes
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_46-24-01.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 46-24-01 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; BOEING Model A75L3, 75, A75, B75, E75, A75J1, A75N1, B75N1, D75N1 Series Aircraft Subject: Wing Drain Holes Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: Make: Boeing Airplane Company, Wichita Division Model: 75 (Army PT-13) | A75 (Army PT-13A, -13B, -13C) | A75J1 (Army PT-18) | A75L3 | A75N1 (Army PT-17, -1...Show more 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: 46-24-01 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 46-24-01 SUBJECT HEADING: Airworthiness Directives; BOEING Model A75L3, 75, A75, B75, E75, A75J1, A75N1, B75N1, D75N1 Series Aircraft ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 46-24-01 BOEING: (Was Mandatory Note 4 of AD-743-3.) Applies to A75L3, 75, A75, B75, E75, A75J1, A75N1, B75N1, D75N1 Series Aircraft. Compliance required at next periodic inspection. The lower wings lack adequate drainage just forward of the ailerons with the result that water is entrapped by the dural angle forming the lower rear edge of the wing at the aileron gap. Since this will cause eventual deterioration of the rib ends a No. 30 hole should be drilled through the fabric and the dural angle just outboard of the rib at the inboard end of the aileron cutout and each of the 12 ribs outboard of this station. The holes should be drilled aft of the rear spar and just forward of the 120 degrees bend in the dural angle. Care should be exercised to avoid damage to the rear spar while effecting this work. As a safety measure, a stop should be used on the drill to prevent penetration in excess of 1/2 inch. FOOTER:
Document Text
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AD Final Rules - DRS_46-24-01.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 46-24-01 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; BOEING Model A75L3, 75, A75, B75, E75, A75J1, A75N1, B75N1, D75N1 Series Aircraft Subject: Wing Drain Holes Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: Make: Boeing Airplane Company, Wichita Division Model: 75 (Army PT-13) | A75 (Army PT-13A, -13B, -13C) | A75J1 (Army PT-18) | A75L3 | A75N1 (Army PT-17, -1...Show more 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: 46-24-01 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 46-24-01 SUBJECT HEADING: Airworthiness Directives; BOEING Model A75L3, 75, A75, B75, E75, A75J1, A75N1, B75N1, D75N1 Series Aircraft ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 46-24-01 BOEING: (Was Mandatory Note 4 of AD-743-3.) Applies to A75L3, 75, A75, B75, E75, A75J1, A75N1, B75N1, D75N1 Series Aircraft. Compliance required at next periodic inspection. The lower wings lack adequate drainage just forward of the ailerons with the result that water is entrapped by the dural angle forming the lower rear edge of the wing at the aileron gap. Since this will cause eventual deterioration of the rib ends a No. 30 hole should be drilled through the fabric and the dural angle just outboard of the rib at the inboard end of the aileron cutout and each of the 12 ribs outboard of this station. The holes should be drilled aft of the rear spar and just forward of the 120 degrees bend in the dural angle. Care should be exercised to avoid damage to the rear spar while effecting this work. As a safety measure, a stop should be used on the drill to prevent penetration in excess of 1/2 inch. 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.
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