AD 53-21-01
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Viking Air Limited | DHC-2 Mk.I | Airworthiness Directives; de Havilland Model DHC-2 (Beaver) Aircraft |
| aircraft | Viking Air Limited | DHC-2 Mk.II | Airworthiness Directives; de Havilland Model DHC-2 (Beaver) Aircraft |
| aircraft | Viking Air Limited | DHC-2 Mk.III | Airworthiness Directives; de Havilland Model DHC-2 (Beaver) Aircraft |
Unsafe Condition
Installation of extra washers, packing, or bushings in the wing rear spar attachment bolt fitting, which could interfere with the intended clearance designed to accommodate drag loads.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Inspect all Beaver aircraft to ensure no washers, bushings, or spacers are installed in the rear spar wing bolt fitting. Remove any such items found. Ensure proper assembly by attaching the front spar first and not packing gaps with washers or spacers.
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 December 1, 1953.
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
Viking Air Limited DHC-2 Mk.I, DHC-2 Mk.II, DHC-2 Mk.III aircraft.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Wing Rear Spar Attachment Bolt
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_53-21-01.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 53-21-01 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; de Havilland Model DHC-2 (Beaver) Aircraft Subject: Wing Rear Spar Attachment Bolt Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: Make: Viking Air Limited Model: DHC-2 Mk.I | DHC-2 Mk.II | DHC-2 Mk.III Product Type: Aircraft Product Subtype: Small Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 53-21-01 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 53-21-01 SUBJECT HEADING: Airworthiness Directives; de Havilland Model DHC-2 (Beaver) Aircraft ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 53-21-01 de HAVILLAND: Applies to All Model DHC-2 (Beaver) Aircraft. Compliance required as indicated. Several cases have been reported where mechanics in the field upon assembling DHC-2 wings to fuselage have installed extra washers, packing, etc., to the rear spar wing bolt in order to take out any end play. It should be pointed out that a clearance is purposely provided in this fitting as the rear wing attachment is not designed to take drag loads. All Beaver aircraft should be inspected as soon as possible but not later than December 1, 1953, to see that no washers, bushings, etc., have been installed in this fitting and if found they should be removed immediately. In assembling the wing to fuselage, the front spar must be attached and then the rear wing bolt should be installed. It is quite normal that the rear spar wing fitting should not touch either inboard side of the fuselage fitting, but in most cases the wing fitting is almost against the forward side. The gaps in the fittings front and rear should not be packed with washers or spacers. The FAA concurs in this mandatory action by the Canadian Department of Transport. (de Havilland Technical News Sheet, Series B, No. 67, dated August 31, 1953, available from de Havilland Aircraft of Canada, Ltd., Toronto, Ontario, Canada, covers this same subject.) FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_53-21-01.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 53-21-01 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; de Havilland Model DHC-2 (Beaver) Aircraft Subject: Wing Rear Spar Attachment Bolt Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: Make: Viking Air Limited Model: DHC-2 Mk.I | DHC-2 Mk.II | DHC-2 Mk.III 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: 53-21-01 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 53-21-01 SUBJECT HEADING: Airworthiness Directives; de Havilland Model DHC-2 (Beaver) Aircraft ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 53-21-01 de HAVILLAND: Applies to All Model DHC-2 (Beaver) Aircraft. Compliance required as indicated. Several cases have been reported where mechanics in the field upon assembling DHC-2 wings to fuselage have installed extra washers, packing, etc., to the rear spar wing bolt in order to take out any end play. It should be pointed out that a clearance is purposely provided in this fitting as the rear wing attachment is not designed to take drag loads. All Beaver aircraft should be inspected as soon as possible but not later than December 1, 1953, to see that no washers, bushings, etc., have been installed in this fitting and if found they should be removed immediately. In assembling the wing to fuselage, the front spar must be attached and then the rear wing bolt should be installed. It is quite normal that the rear spar wing fitting should not touch either inboard side of the fuselage fitting, but in most cases the wing fitting is almost against the forward side. The gaps in the fittings front and rear should not be packed with washers or spacers. The FAA concurs in this mandatory action by the Canadian Department of Transport. (de Havilland Technical News Sheet, Series B, No. 67, dated August 31, 1953, available from de Havilland Aircraft of Canada, Ltd., Toronto, Ontario, Canada, covers this same subject.) FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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