AD 86-23-07

final rule

Airworthiness Directives; British Aerospace Model B.121 Series Airplanes

AD Number
86-23-07
Status
final_rule
Effective Date
Product Category
aircraft
Docket
Unknown
FR Citation
This information is not available.

Applicability

TypeManufacturerModelDetails
aircraft DeHavilland Support Limited Beagle B.121 Series 1 Airworthiness Directives; British Aerospace Model B.121 Series Airplanes
aircraft DeHavilland Support Limited Beagle B.121 Series 2 Airworthiness Directives; British Aerospace Model B.121 Series Airplanes
aircraft DeHavilland Support Limited Beagle B.121 Series 3 Airworthiness Directives; British Aerospace Model B.121 Series Airplanes

Unsafe Condition

Cracks in the vertical fin/fuselage attachment structure, specifically in the Center Angle (P/N BE-10-10085), Diaphragm Decking upper (P/N BE-10-10155/1), and the heel of the side skin attachment flange adjacent to the tailplane front spar attachment bolts, could lead to structural failure.

AI-generated summary from the source AD text. Verify against the official source before acting.

Required Actions

Visually inspect for cracks in specified areas of the vertical fin/fuselage structure as outlined in BAe Service Bulletin B121/86. If cracks exceed limits, repair with manufacturer-approved instructions from British Aerospace and FAA approval. Repeat inspections every 50 hours time-in-service if no cracks or within limits.

AI-generated summary from the source AD text. Verify against the official source before acting.

Compliance Time

Initially within 50 hours time-in-service for airplanes having or upon accumulating 2,450 hours or more TIS, and thereafter at intervals of 50 hours TIS

AI-generated summary from the source AD text. Verify against the official source before acting.

Affected Aircraft

British Aerospace Model B.121 Series I, II, and III (all serial numbers)

AI-generated summary from the source AD text. Verify against the official source before acting.

Federal Register Abstract

Vertical Fin/Fuselage Structure

Applicability Source Text

Show captured applicability text from the source AD
AD Final Rules - DRS_86-23-07.html
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AD Number:
86-23-07
Document Type:
AD Final Rules
Docket Number:
Unknown
Subject Heading:
Airworthiness Directives; British Aerospace Model B.121 Series Airplanes
Subject:
Vertical Fin/Fuselage Structure
Status:
Current
Citation:
This information is not available.
Citation Publish Date:
Effective Date:
12/18/1986
Make:
DeHavilland Support Limited
Model:
Beagle B.121 Series 1 | Beagle B.121 Series 2 | Beagle B.121 Series 3
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: 86-23-07
CITATION:   This information is not available.

PAGE NUMBER:  

DOCKET NUMBER:   Unknown

AMENDMENT:   39-5464

AD NUMBER:   86-23-07

SUBJECT HEADING:   Airworthiness Directives; British Aerospace Model B.121 Series Airplanes

ACTION:  

SUMMARY:  

DATES:   Effective December 18, 1986.

ADDRESSES:  

FOR FURTHER INFORMATION CONTACT:  

SUPPLEMENTARY INFORMATION:  

REGULATORY TEXT:  
86-23-07 BRITISH AEROSPACE: Amendment 39-5464. Applies to Model B.121 Series I, II, and III (all serial numbers) airplanes certificated in any category.

Compliance: Required initially within 50 hours time-in-service (TIS) for airplanes having or upon accumulating 2,450 hours or more TIS, and thereafter at intervals of 50 hours TIS, unless already accomplished.

To assure the integrity of the vertical fin/fuselage attachment structure, accomplish the following:

(a) Visually inspect for cracks in the following areas:

(1) Center Angle, Part Number (P/N) BE-10-10085 in accordance with paragraph 3. "ACTION" subparagraph (c) of British Aerospace (BAe) Service Bulletin (S/B) No. B121/86, dated March 29, 1984.

(i) If cracks are found that equal or exceed the conditions shown in paragraph 3. "ACTION" subparagraph (c) of BAe S/B No. B121/86, prior to further flight, repair in accordance with repair instructions obtained from the manufacturer, British Aerospace, and approved by the Manager, Aircraft Certification Staff, AEU-100, Europe, Africa and Middle East Office, FAA, c/o American Embassy, 1000 Brussels, Belgium (hereinafter referred to as "Manager, AEU-100").

(ii) If no cracks are found or if cracks do not exceed the limits shown in paragraph 3. "ACTION" subparagraph (d) of BAe S/B No. B121/86, repeat the inspection at intervals not exceeding 50 hours TIS.

(2) The underside of Diaphragm Decking upper, P/N BE-10-10155/1, in accordance with paragraph 3. "ACTION" subparagraph (d) of BAe S/B No. B121/86, dated March 29, 1984.

(i) If cracks are found, prior to further flight, repair in accordance with repair instructions obtained from the manufacturer, British Aerospace, and approved by the Manager, AEU-100.

(ii) If no cracks are found, repeat the inspection at intervals not exceeding 50 hours TIS.

(3) The heel of the side skin attachment flange (left and right) adjacent to the tailplane front spar attachment bolts in accordance with paragraph 3. "ACTION" subparagraph (e) of BAe S/B No. B121/86, dated March 29, 1984.

(i) If cracks are found, prior to further flight, repair in accordance with repair instructions obtained from the manufacturer, British Aerospace, and approved by the Manager, AEU-100.

(ii) If no cracks are found, repeat the inspection at intervals not exceeding 50 hours TIS.

(b) Extension or elimination of the repetitive inspections specified in this AD may be included as part of the FAA-approved repair obtained in accordance with paragraphs (a)(1)(i), (a)(2)(i), and (a)(3)(i) of this AD.

(c) Aircraft may be flown in accordance with Federal Aviation Regulation 21.197 to a location where this AD can be accomplished.

(d) An equivalent means of compliance with this AD may be used if approved by the Manager, Aircraft Certification Staff, AEU-100, Europe, Africa and Middle East Office, FAA, c/o American Embassy, 1000 Brussels, Belgium.

All persons affected by this directive may obtain a copy of the document referred to herein upon request to British Aerospace, Engineering Department, Post Office Box 17414, Dulles International Airport, Washington, D.C. 20041; Telephone (703) 435-9100, or FAA, Office of the Regional Counsel, Room 1558, 601 East 12th Street, Kansas City, Missouri 64106.

This amendment becomes effective on December 18, 1986.

FOOTER:

Document Text

Show stored source text (verify against official source)
AD Final Rules - DRS_86-23-07.html
Copy URL
Print/Save as PDF
Document Versions
 Feedback
Details
AD Number:
86-23-07
Document Type:
AD Final Rules
Docket Number:
Unknown
Subject Heading:
Airworthiness Directives; British Aerospace Model B.121 Series Airplanes
Subject:
Vertical Fin/Fuselage Structure
Status:
Current
Citation:
This information is not available.
Citation Publish Date:
Effective Date:
12/18/1986
Make:
DeHavilland Support Limited
Model:
Beagle B.121 Series 1 | Beagle B.121 Series 2 | Beagle B.121 Series 3
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: 86-23-07
CITATION:   This information is not available.

PAGE NUMBER:  

DOCKET NUMBER:   Unknown

AMENDMENT:   39-5464

AD NUMBER:   86-23-07

SUBJECT HEADING:   Airworthiness Directives; British Aerospace Model B.121 Series Airplanes

ACTION:  

SUMMARY:  

DATES:   Effective December 18, 1986.

ADDRESSES:  

FOR FURTHER INFORMATION CONTACT:  

SUPPLEMENTARY INFORMATION:  

REGULATORY TEXT:  
86-23-07 BRITISH AEROSPACE: Amendment 39-5464. Applies to Model B.121 Series I, II, and III (all serial numbers) airplanes certificated in any category.

Compliance: Required initially within 50 hours time-in-service (TIS) for airplanes having or upon accumulating 2,450 hours or more TIS, and thereafter at intervals of 50 hours TIS, unless already accomplished.

To assure the integrity of the vertical fin/fuselage attachment structure, accomplish the following:

(a) Visually inspect for cracks in the following areas:

(1) Center Angle, Part Number (P/N) BE-10-10085 in accordance with paragraph 3. "ACTION" subparagraph (c) of British Aerospace (BAe) Service Bulletin (S/B) No. B121/86, dated March 29, 1984.

(i) If cracks are found that equal or exceed the conditions shown in paragraph 3. "ACTION" subparagraph (c) of BAe S/B No. B121/86, prior to further flight, repair in accordance with repair instructions obtained from the manufacturer, British Aerospace, and approved by the Manager, Aircraft Certification Staff, AEU-100, Europe, Africa and Middle East Office, FAA, c/o American Embassy, 1000 Brussels, Belgium (hereinafter referred to as "Manager, AEU-100").

(ii) If no cracks are found or if cracks do not exceed the limits shown in paragraph 3. "ACTION" subparagraph (d) of BAe S/B No. B121/86, repeat the inspection at intervals not exceeding 50 hours TIS.

(2) The underside of Diaphragm Decking upper, P/N BE-10-10155/1, in accordance with paragraph 3. "ACTION" subparagraph (d) of BAe S/B No. B121/86, dated March 29, 1984.

(i) If cracks are found, prior to further flight, repair in accordance with repair instructions obtained from the manufacturer, British Aerospace, and approved by the Manager, AEU-100.

(ii) If no cracks are found, repeat the inspection at intervals not exceeding 50 hours TIS.

(3) The heel of the side skin attachment flange (left and right) adjacent to the tailplane front spar attachment bolts in accordance with paragraph 3. "ACTION" subparagraph (e) of BAe S/B No. B121/86, dated March 29, 1984.

(i) If cracks are found, prior to further flight, repair in accordance with repair instructions obtained from the manufacturer, British Aerospace, and approved by the Manager, AEU-100.

(ii) If no cracks are found, repeat the inspection at intervals not exceeding 50 hours TIS.

(b) Extension or elimination of the repetitive inspections specified in this AD may be included as part of the FAA-approved repair obtained in accordance with paragraphs (a)(1)(i), (a)(2)(i), and (a)(3)(i) of this AD.

(c) Aircraft may be flown in accordance with Federal Aviation Regulation 21.197 to a location where this AD can be accomplished.

(d) An equivalent means of compliance with this AD may be used if approved by the Manager, Aircraft Certification Staff, AEU-100, Europe, Africa and Middle East Office, FAA, c/o American Embassy, 1000 Brussels, Belgium.

All persons affected by this directive may obtain a copy of the document referred to herein upon request to British Aerospace, Engineering Department, Post Office Box 17414, Dulles International Airport, Washington, D.C. 20041; Telephone (703) 435-9100, or FAA, Office of the Regional Counsel, Room 1558, 601 East 12th Street, Kansas City, Missouri 64106.

This amendment becomes effective on December 18, 1986.

FOOTER:

Source: Official FAA Source ↗

Retrieved: Apr 8, 2026

Rights: U.S. Government Public Domain

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