AD 75-17-12
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Slingsby Aviation Ltd. | T.59.D Kestrel | Airworthiness Directives; Slingsby T59D Kestrel Gliders |
Unsafe Condition
Dive brake retraction failure
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Required Actions
Install a placard on the instrument panel within 10 hours' time in service, and replace the dive brake control mechanism with P/N 59A-45-717 within 50 hours' time in service. The placard may be removed after completing the mechanism replacement.
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Compliance Time
within the next 10 hours' time in service after the effective date of this AD (for placard installation) and within the next 50 hours' time in service after the effective date (for mechanism replacement)
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Affected Aircraft
Slingsby Aviation Ltd. T59D Kestrel gliders certificated in all categories
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Federal Register Abstract
Dive Brake Retraction Failure
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_75-17-12.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 75-17-12 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Slingsby T59D Kestrel Gliders Subject: Dive Brake Retraction Failure Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 08/18/1975 Make: Slingsby Aviation Ltd. Model: T.59.D Kestrel Product Type: Aircraft Product Subtype: Glider Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 75-17-12 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-2314 AD NUMBER: 75-17-12 SUBJECT HEADING: Airworthiness Directives; Slingsby T59D Kestrel Gliders ACTION: SUMMARY: DATES: Effective August 18, 1975. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 75-17-12 SLINGSBY SAILPLANES: Amendment 39-2314. Applies to Slingsby T59D Kestrel gliders certificated in all categories. Compliance is required as indicated, unless already accomplished. To prevent dive brake retraction failure, accomplish the following: (a) Within the next 10 hours' time in service after the effective date of this AD, install a placard on the instrument panel in full view of the pilot reading: "AIR BRAKE EXTENSION LIMITATION FINAL APPROACH 50% FLAREOUT ON LANDING 100% CRUISE NONE (0%)" (b) Within the next 50 hours' time in service after the effective date of this AD, replace the dive brake control mechanism with the linear type dive brake control mechanism, P/N 59A-45-717, in accordance with Slingsby Sailplanes Technical Instruction No. 75 dated May 21, 1975, or an FAA approved equivalent. (c) The placard required by paragraph (a) of this AD may be removed after the work specified in paragraph (b) of this AD has been accomplished. This amendment becomes effective August 18, 1975. FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_75-17-12.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 75-17-12 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Slingsby T59D Kestrel Gliders Subject: Dive Brake Retraction Failure Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 08/18/1975 Make: Slingsby Aviation Ltd. Model: T.59.D Kestrel Product Type: Aircraft Product Subtype: Glider Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 75-17-12 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-2314 AD NUMBER: 75-17-12 SUBJECT HEADING: Airworthiness Directives; Slingsby T59D Kestrel Gliders ACTION: SUMMARY: DATES: Effective August 18, 1975. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 75-17-12 SLINGSBY SAILPLANES: Amendment 39-2314. Applies to Slingsby T59D Kestrel gliders certificated in all categories. Compliance is required as indicated, unless already accomplished. To prevent dive brake retraction failure, accomplish the following: (a) Within the next 10 hours' time in service after the effective date of this AD, install a placard on the instrument panel in full view of the pilot reading: "AIR BRAKE EXTENSION LIMITATION FINAL APPROACH 50% FLAREOUT ON LANDING 100% CRUISE NONE (0%)" (b) Within the next 50 hours' time in service after the effective date of this AD, replace the dive brake control mechanism with the linear type dive brake control mechanism, P/N 59A-45-717, in accordance with Slingsby Sailplanes Technical Instruction No. 75 dated May 21, 1975, or an FAA approved equivalent. (c) The placard required by paragraph (a) of this AD may be removed after the work specified in paragraph (b) of this AD has been accomplished. This amendment becomes effective August 18, 1975. FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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