AD 79-23-05
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Textron Aviation Inc. | 77 | Airworthiness Directives; BEECH Model 77 Airplanes |
Unsafe Condition
Stripped threads or damage to NAS1112-11 or -15 wing main spar to fuselage carry-thru structure attachment bolts or Part Number 108-120010-5 internal nut plates could compromise structural integrity of wing attachment.
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Required Actions
Remove and inspect four NAS1112-11/-15 bolts and internal nut plates for stripped threads or damage. Replace damaged bolts or nut plates with new components. Modify, apply zinc chromate primer, and install correct AN960-1216 washers with Part Number 108-120013-1 radius washers. Ensure safety wire holes in bolt heads meet specified dimensions if using locally sourced bolts.
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Compliance Time
Prior to the next flight
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Affected Aircraft
BEECH Model 77 airplanes with serial numbers WA-1 through WA-39, WA-41, WA-42, and WA-44 through WA-46
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Federal Register Abstract
Attachment Bolts Threads and Nut Plates
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_79-23-05.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 79-23-05 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; BEECH Model 77 Airplanes Subject: Attachment Bolts Threads and Nut Plates Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 11/19/1979 Make: Textron Aviation Inc. Model: 77 Product Type: Aircraft Product Subtype: Small Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 79-23-05 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-3611 AD NUMBER: 79-23-05 SUBJECT HEADING: Airworthiness Directives; BEECH Model 77 Airplanes ACTION: SUMMARY: DATES: Effective November 19, 1979. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 79-23-05 BEECH: Amendment 39-3611. Applies to Model 77 (S/N's WA-1 through WA-39, WA-41, WA-42 and WA-44 through WA-46) airplanes certificated in all categories. COMPLIANCE: Required as indicated unless already accomplished. To assure structural integrity of the attachment of the left and right wing to the fuselage carry-thru structure, accomplish the following: A) Prior to the next flight, in accordance with instructions in (1) Beech Mailgram sent to owners on October 3, 1979 or (2) Beechcraft Service Instructions No. 1088 (whichever is available): 1. Remove the four NAS1112-11 or -15 wing main spar to fuselage carry- thru structure attachment bolts and visually inspect (1) the threads on the bolts and (2) the threads in the Part Number 108-120010-5 internal nut plate for each bolt, for stripped threads or other damage. 2. Replace any damaged NAS1112-11 or -15 bolts or any Part Number 108-120010-5 internal nut plates with new components. NOTE: If new NAS1112 bolts are obtained locally, the heads must have a .093 to .103 inch diameter hole drilled in them to accommodate MS20995-NC32 safety wire. Locate the hole in the bolt head at approximately the same location as the safety wire hole in the bolt removed. 3. Modify, apply zinc chromate primer to, and install the correct number of AN960-1216 washers under the NAS1112-11 or -15 bolts. NOTE: The Beech Part Number 108-120013-1 radius washer must be installed between the AN960-1216 washers and the main spar tube on each of the four NAS1112-11 or - 15 bolts. The total shank length of a NAS1112-11 bolt is 1.26 inches and for the NAS1112-15 1.51 inches. B) Aircraft may be flown in accordance with Federal Aviation Regulation 21.197 to a location where this AD can be accomplished provided that inspection of each of the four NAS1112-11 or -15 wing main spar to fuselage carry-thru attachment bolts shows that all four bolts are (1) in place, (2) safety wired in place and (3) secure when an attempt is made to turn or pull the bolts by hand. This inspection must be accomplished by an FAA certificated aircraft mechanic or persons authorized under Federal Aviation Regulations 43.3. C) Any equivalent method of compliance with this AD must be approved by the Chief, Engineering and Manufacturing Branch, FAA, Central Region. This amendment becomes effective on November 19, 1979, to all persons except those to whom it has already been made effective by an airmail letter from the FAA dated October 5, 1979. FOOTER:
Document Text
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AD Final Rules - DRS_79-23-05.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 79-23-05 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; BEECH Model 77 Airplanes Subject: Attachment Bolts Threads and Nut Plates Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 11/19/1979 Make: Textron Aviation Inc. Model: 77 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: 79-23-05 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-3611 AD NUMBER: 79-23-05 SUBJECT HEADING: Airworthiness Directives; BEECH Model 77 Airplanes ACTION: SUMMARY: DATES: Effective November 19, 1979. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 79-23-05 BEECH: Amendment 39-3611. Applies to Model 77 (S/N's WA-1 through WA-39, WA-41, WA-42 and WA-44 through WA-46) airplanes certificated in all categories. COMPLIANCE: Required as indicated unless already accomplished. To assure structural integrity of the attachment of the left and right wing to the fuselage carry-thru structure, accomplish the following: A) Prior to the next flight, in accordance with instructions in (1) Beech Mailgram sent to owners on October 3, 1979 or (2) Beechcraft Service Instructions No. 1088 (whichever is available): 1. Remove the four NAS1112-11 or -15 wing main spar to fuselage carry- thru structure attachment bolts and visually inspect (1) the threads on the bolts and (2) the threads in the Part Number 108-120010-5 internal nut plate for each bolt, for stripped threads or other damage. 2. Replace any damaged NAS1112-11 or -15 bolts or any Part Number 108-120010-5 internal nut plates with new components. NOTE: If new NAS1112 bolts are obtained locally, the heads must have a .093 to .103 inch diameter hole drilled in them to accommodate MS20995-NC32 safety wire. Locate the hole in the bolt head at approximately the same location as the safety wire hole in the bolt removed. 3. Modify, apply zinc chromate primer to, and install the correct number of AN960-1216 washers under the NAS1112-11 or -15 bolts. NOTE: The Beech Part Number 108-120013-1 radius washer must be installed between the AN960-1216 washers and the main spar tube on each of the four NAS1112-11 or - 15 bolts. The total shank length of a NAS1112-11 bolt is 1.26 inches and for the NAS1112-15 1.51 inches. B) Aircraft may be flown in accordance with Federal Aviation Regulation 21.197 to a location where this AD can be accomplished provided that inspection of each of the four NAS1112-11 or -15 wing main spar to fuselage carry-thru attachment bolts shows that all four bolts are (1) in place, (2) safety wired in place and (3) secure when an attempt is made to turn or pull the bolts by hand. This inspection must be accomplished by an FAA certificated aircraft mechanic or persons authorized under Federal Aviation Regulations 43.3. C) Any equivalent method of compliance with this AD must be approved by the Chief, Engineering and Manufacturing Branch, FAA, Central Region. This amendment becomes effective on November 19, 1979, to all persons except those to whom it has already been made effective by an airmail letter from the FAA dated October 5, 1979. FOOTER:
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Retrieved: Apr 8, 2026
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