AD 78-23-14 R1
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | BLANIK LIMITED | Blanik L-13 | Airworthiness Directives: LET BLANIK Model L-13 Gliders |
| aircraft | BLANIK LIMITED | Blanik L-13 AC | Airworthiness Directives: LET BLANIK Model L-13 Gliders |
Unsafe Condition
Tow release malfunction due to structural cracks at the attach point of the tow release system countershaft bracket.
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Required Actions
Inspect the No. 1 bulkhead for cracks at the attach points of the tow release system countershaft brackets within 10 hours time in service after the effective date. If cracks are found, repair and reinforce the bulkhead per specified procedures before further flight. If no cracks are found, reinspect within 100 hours time in service.
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Compliance Time
within the next 10 hours time in-service after the effective date of this AD
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Affected Aircraft
BLANIK LIMITED Model L-13 gliders, Serial Numbers 170101 through 174730
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Federal Register Abstract
Tow Release System
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_78-23-14_R.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 78-23-14 R1 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives: LET BLANIK Model L-13 Gliders Subject: Tow Release System Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 08/17/1984 Make: BLANIK LIMITED Model: Blanik L-13 | Blanik L-13 AC Product Type: Aircraft Product Subtype: Glider Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 78-23-14 R1 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-4894 AD NUMBER: 78-23-14 R1 SUBJECT HEADING: Airworthiness Directives: LET BLANIK Model L-13 Gliders ACTION: SUMMARY: DATES: Effective August 17, 1984. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 78-23-14 R1 LET BLANIK: Amendment 38-3349 as amended by Amendment 39-4894. Applies to Model L-13 gliders, Serial Numbers 170101 through 174730, certificated in all categories. Compliance is required as indicated, unless already accomplished. To prevent tow release malfunction due to structural cracks at the attach point of the tow release system countershaft bracket, accomplish the following: (a) Within the next 10 hours time in service after the effective date of this AD, inspect the No. 1 bulkhead for cracks at the attach points of the tow release system countershaft brackets in accordance with Let Mandatory Bulletin No. L13/047 dated January 11, 1978, and Note 2 in Bulletin No. L13/047 (Supplement), dated April 1, 1978, or an equivalent procedure approved by the Manager, Aircraft Certification Staff, Europe, Africa and Middle East Office. (b) If cracks are found during inspection in accordance with paragraph (a) of this AD, before further flight: (1) Where cracks do not exceed 6 mm in length, repair and reinforce the No. 1 bulkhead in accordance with paragraph A, "Reinforcement of bulkhead No. 1" of Let Mandatory Bulletin No. L13/047 dated January 11, 1978, and Bulletin L13/047 (Supplement) dated April 1, 1978, or equivalent approved by the Manager, Aircraft Certification Staff, Europe, Africa and Middle East Office; or, (2) Where cracks exceed 6 mm in length, repair and reinforce the No. 1 bulkhead in accordance with the metal repair procedures, Section 3 of FAA Advisory Circular 43.13-1A, or equivalent approved by the Manager, Aircraft Certification Staff, Europe, Africa, and Middle East Office. (c) If no cracks are found during the inspection required by paragraph (a) of this AD, within the next 100 hours time in service after the effective date of this AD, reinspect, repair, and reinforce the No. 1 bulkhead as follows: (1) If no cracks have developed, in accordance with the method specified in paragraph (b)(1) of this AD; or (2) If cracks have developed, in accordance with the applicable method specified in paragraph (b) of this AD. Amendment 38-3349 became effective November 27, 1978. This Amendment 39-4894 becomes effective August 17, 1984. FOOTER:
Document Text
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AD Final Rules - DRS_78-23-14_R.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 78-23-14 R1 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives: LET BLANIK Model L-13 Gliders Subject: Tow Release System Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 08/17/1984 Make: BLANIK LIMITED Model: Blanik L-13 | Blanik L-13 AC 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: 78-23-14 R1 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-4894 AD NUMBER: 78-23-14 R1 SUBJECT HEADING: Airworthiness Directives: LET BLANIK Model L-13 Gliders ACTION: SUMMARY: DATES: Effective August 17, 1984. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 78-23-14 R1 LET BLANIK: Amendment 38-3349 as amended by Amendment 39-4894. Applies to Model L-13 gliders, Serial Numbers 170101 through 174730, certificated in all categories. Compliance is required as indicated, unless already accomplished. To prevent tow release malfunction due to structural cracks at the attach point of the tow release system countershaft bracket, accomplish the following: (a) Within the next 10 hours time in service after the effective date of this AD, inspect the No. 1 bulkhead for cracks at the attach points of the tow release system countershaft brackets in accordance with Let Mandatory Bulletin No. L13/047 dated January 11, 1978, and Note 2 in Bulletin No. L13/047 (Supplement), dated April 1, 1978, or an equivalent procedure approved by the Manager, Aircraft Certification Staff, Europe, Africa and Middle East Office. (b) If cracks are found during inspection in accordance with paragraph (a) of this AD, before further flight: (1) Where cracks do not exceed 6 mm in length, repair and reinforce the No. 1 bulkhead in accordance with paragraph A, "Reinforcement of bulkhead No. 1" of Let Mandatory Bulletin No. L13/047 dated January 11, 1978, and Bulletin L13/047 (Supplement) dated April 1, 1978, or equivalent approved by the Manager, Aircraft Certification Staff, Europe, Africa and Middle East Office; or, (2) Where cracks exceed 6 mm in length, repair and reinforce the No. 1 bulkhead in accordance with the metal repair procedures, Section 3 of FAA Advisory Circular 43.13-1A, or equivalent approved by the Manager, Aircraft Certification Staff, Europe, Africa, and Middle East Office. (c) If no cracks are found during the inspection required by paragraph (a) of this AD, within the next 100 hours time in service after the effective date of this AD, reinspect, repair, and reinforce the No. 1 bulkhead as follows: (1) If no cracks have developed, in accordance with the method specified in paragraph (b)(1) of this AD; or (2) If cracks have developed, in accordance with the applicable method specified in paragraph (b) of this AD. Amendment 38-3349 became effective November 27, 1978. This Amendment 39-4894 becomes effective August 17, 1984. FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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