AD 76-26-04
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | British Aerospace Regional Aircraft | H.P. 137 Jetstream Mk. 1 | Airworthiness Directives; Scottish Aviation Limited Model HP- 137 Mk. 1 Jetstream Airplanes |
Unsafe Condition
Cracks along the lower flange of the end rib and rib doubler at the outer end of each outer wing flap could lead to flap separation and possible loss of airplane control.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Visually inspect the outer end of each outer wing flap using a magnifying glass with at least 5 power per Service Bulletin 9/5, issue 2. Radiographically inspect the same area per Service Bulletin 9/5, issue 2. Replace cracked parts with serviceable parts of the same part number.
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Compliance Time
Before further flight (with exceptions for flights to a base where work can be performed with flaps fully retracted) and at intervals not to exceed 50 landings for visual inspections, and within the next 50 landings followed by intervals not to exceed 500 landings for radiographic inspections. Compliance may be discontinued after installing Modification No. 5111.
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Affected Aircraft
Scottish Aviation Limited Model HP-137 Mk. 1 Jetstream airplanes except those with Modification No. 5111.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Flap Separation
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_76-26-04.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 76-26-04 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Scottish Aviation Limited Model HP- 137 Mk. 1 Jetstream Airplanes Subject: Flap Separation Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 01/06/1977 Make: British Aerospace Regional Aircraft Model: H.P. 137 Jetstream Mk. 1 Product Type: Aircraft Product Subtype: Small/Large Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 76-26-04 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-2793 AD NUMBER: 76-26-04 SUBJECT HEADING: Airworthiness Directives; Scottish Aviation Limited Model HP- 137 Mk. 1 Jetstream Airplanes ACTION: SUMMARY: DATES: Effective January 6, 1977. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 76-26-04 SCOTTISH AVIATION LIMITED: Amendment 39-2793. Applies to Model HP- 137 Mk. 1 Jetstream airplanes, certificated in all categories, except those airplanes which incorporate Scottish Aviation Limited Modification No. 5111. Compliance is required as indicated. To detect cracks in the outer end of each outer wing flap and to prevent possible flap separation from the airplane and possible loss of airplane control, accomplish the following: (a) For airplanes with 500 or more total landings on the effective date of this AD: (1) Comply with paragraph (c) of this AD, before further flight, (except that the airplane may be flown in accordance with FAR Sections 21.197 and 21.199 to a base where the work can be performed, provided that the flaps remain in the fully retracted position for the duration of the flight,) unless already accomplished within the last 50 landings and thereafter continue to comply with paragraph (c) of this AD at intervals not to exceed 50 landings. (2) Comply with paragraph (d) of this AD, within the next 50 landings and thereafter continue to comply with paragraph (d) at intervals not to exceed 500 landings. (b) For airplanes with less than 500 total landings on the effective date of this AD: (1) Comply with paragraph (c) of this AD before the accumulation of 500 landings and thereafter continue to comply with paragraph (c) at intervals not to exceed 50 landings. (2) Comply with paragraph (d) of this AD before the accumulation of 500 landings or within the next 50 landings after the effective date of this AD whichever occurs later, and thereafter continue to comply with paragraph (d) at intervals not to exceed 500 landings. (c) Visually inspect the outer end of each outer wing flap, Part No. 13760B-405 (left) and 13760B-406 (right), for cracks along the lower flange of the end rib and rib doubler using a magnifying glass with at least 5 power in accordance with the instructions contained in Paragraph 3, Part B of Scottish Aviation Limited Service Bulletin No. 9/5, issue 2, dated August 4, 1976, or an FAA-approved equivalent. (d) Inspect the outer end of each outer wing flap, Part No. 13760-B-405 (left) and 13760B-406 (right), for cracks along the lower flange of the end rib and rib doubler using the radiographic technique in accordance with the instructions contained in Paragraph 3, Part C of Scottish Aviation Limited Service Bulletin No. 9/5, issue 2, dated August 4, 1976, or an FAA- approved equivalent. (e) If, during the inspections required by paragraph (c) and (d) of this AD, cracks are found, replace the affected part with a serviceable part of the same part number. NOTE: A "serviceable part" is defined in Note 1, Parts (a) and (b) of Scottish Aviation Limited Service Bulletin, No. 9/5, issue 2, dated August 4, 1976. (f) Compliance with paragraphs (a)(1), (a)(2), (b)(1), and (b)(2) may be discontinued upon the incorporation of Scottish Aviation Limited Modification 5111. This amendment supersedes Amendment 39-2465, (40FR 58129), AD 75-26-16. This amendment becomes effective January 6, 1977. FOOTER:
Document Text
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AD Final Rules - DRS_76-26-04.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 76-26-04 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Scottish Aviation Limited Model HP- 137 Mk. 1 Jetstream Airplanes Subject: Flap Separation Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 01/06/1977 Make: British Aerospace Regional Aircraft Model: H.P. 137 Jetstream Mk. 1 Product Type: Aircraft Product Subtype: Small/Large 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: 76-26-04 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-2793 AD NUMBER: 76-26-04 SUBJECT HEADING: Airworthiness Directives; Scottish Aviation Limited Model HP- 137 Mk. 1 Jetstream Airplanes ACTION: SUMMARY: DATES: Effective January 6, 1977. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 76-26-04 SCOTTISH AVIATION LIMITED: Amendment 39-2793. Applies to Model HP- 137 Mk. 1 Jetstream airplanes, certificated in all categories, except those airplanes which incorporate Scottish Aviation Limited Modification No. 5111. Compliance is required as indicated. To detect cracks in the outer end of each outer wing flap and to prevent possible flap separation from the airplane and possible loss of airplane control, accomplish the following: (a) For airplanes with 500 or more total landings on the effective date of this AD: (1) Comply with paragraph (c) of this AD, before further flight, (except that the airplane may be flown in accordance with FAR Sections 21.197 and 21.199 to a base where the work can be performed, provided that the flaps remain in the fully retracted position for the duration of the flight,) unless already accomplished within the last 50 landings and thereafter continue to comply with paragraph (c) of this AD at intervals not to exceed 50 landings. (2) Comply with paragraph (d) of this AD, within the next 50 landings and thereafter continue to comply with paragraph (d) at intervals not to exceed 500 landings. (b) For airplanes with less than 500 total landings on the effective date of this AD: (1) Comply with paragraph (c) of this AD before the accumulation of 500 landings and thereafter continue to comply with paragraph (c) at intervals not to exceed 50 landings. (2) Comply with paragraph (d) of this AD before the accumulation of 500 landings or within the next 50 landings after the effective date of this AD whichever occurs later, and thereafter continue to comply with paragraph (d) at intervals not to exceed 500 landings. (c) Visually inspect the outer end of each outer wing flap, Part No. 13760B-405 (left) and 13760B-406 (right), for cracks along the lower flange of the end rib and rib doubler using a magnifying glass with at least 5 power in accordance with the instructions contained in Paragraph 3, Part B of Scottish Aviation Limited Service Bulletin No. 9/5, issue 2, dated August 4, 1976, or an FAA-approved equivalent. (d) Inspect the outer end of each outer wing flap, Part No. 13760-B-405 (left) and 13760B-406 (right), for cracks along the lower flange of the end rib and rib doubler using the radiographic technique in accordance with the instructions contained in Paragraph 3, Part C of Scottish Aviation Limited Service Bulletin No. 9/5, issue 2, dated August 4, 1976, or an FAA- approved equivalent. (e) If, during the inspections required by paragraph (c) and (d) of this AD, cracks are found, replace the affected part with a serviceable part of the same part number. NOTE: A "serviceable part" is defined in Note 1, Parts (a) and (b) of Scottish Aviation Limited Service Bulletin, No. 9/5, issue 2, dated August 4, 1976. (f) Compliance with paragraphs (a)(1), (a)(2), (b)(1), and (b)(2) may be discontinued upon the incorporation of Scottish Aviation Limited Modification 5111. This amendment supersedes Amendment 39-2465, (40FR 58129), AD 75-26-16. This amendment becomes effective January 6, 1977. FOOTER:
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Retrieved: Apr 8, 2026
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