AD 71-23-01
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Pilatus Aircraft Limited | PC-6 | Airworthiness Directives; Pilatus Model PC-6 Airplanes |
| aircraft | Pilatus Aircraft Limited | PC-6-H1 | Airworthiness Directives; Pilatus Model PC-6 Airplanes |
| aircraft | Pilatus Aircraft Limited | PC-6-H2 | Airworthiness Directives; Pilatus Model PC-6 Airplanes |
| aircraft | Pilatus Aircraft Limited | PC-6/350 | Airworthiness Directives; Pilatus Model PC-6 Airplanes |
| aircraft | Pilatus Aircraft Limited | PC-6/350-H1 | Airworthiness Directives; Pilatus Model PC-6 Airplanes |
| aircraft | Pilatus Aircraft Limited | PC-6/350-H2 | Airworthiness Directives; Pilatus Model PC-6 Airplanes |
| aircraft | Pilatus Aircraft Limited | PC-6/A | Airworthiness Directives; Pilatus Model PC-6 Airplanes |
| aircraft | Pilatus Aircraft Limited | PC-6/A-H1 | Airworthiness Directives; Pilatus Model PC-6 Airplanes |
| aircraft | Pilatus Aircraft Limited | PC-6/A-H2 | Airworthiness Directives; Pilatus Model PC-6 Airplanes |
| aircraft | Pilatus Aircraft Limited | PC-6/B-H2 | Airworthiness Directives; Pilatus Model PC-6 Airplanes |
| aircraft | Pilatus Aircraft Limited | PC-6/B1-H2 | Airworthiness Directives; Pilatus Model PC-6 Airplanes |
| aircraft | Pilatus Aircraft Limited | PC-6/C-H2 | Airworthiness Directives; Pilatus Model PC-6 Airplanes |
Unsafe Condition
The use of safety wires on aileron, rudder, elevator, flap, and trim cable turnbuckles that do not meet Military Standard 20995C47, 20995C32, or 33591 specifications for size, corrosion resistance, or method of safetying could result in turnbuckle failure and loss of flight control effectiveness.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Inspect aileron control cable turnbuckles for compliant safety wires before further flight. Inspect rudder, elevator, flap, and trim cable turnbuckles within 50 hours' time in service after the effective date or before November 15, 1971, whichever is sooner. Replace non-compliant safety wires before further flight, allowing flight under FAR 21.197 to a repair base.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Before further flight (for aileron inspections) and within 50 hours' time in service after the effective date or before November 15, 1971, whichever occurs sooner (for other inspections and replacements).
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
Pilatus Model PC-6 (Heli-Porter) airplanes manufactured by Fairchild Hiller.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Safety of Aileron Cable Turnbuckles
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_71-23-01.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 71-23-01 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Pilatus Model PC-6 Airplanes Subject: Safety of Aileron Cable Turnbuckles Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: Make: Pilatus Aircraft Limited Model: PC-6 | PC-6-H1 | PC-6-H2 | PC-6/350 | PC-6/350-H1 | PC-6/350-H2 | PC-6/A | PC-6/A-H1 | PC-6/A-H2 | P...Show more 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: 71-23-01 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-1326 AD NUMBER: 71-23-01 SUBJECT HEADING: Airworthiness Directives; Pilatus Model PC-6 Airplanes ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 71-23-01 PILATUS AIRCRAFT: Amdt. 39-1326. Applies to Pilatus Model PC-6 (Heli-Porter) airplanes manufactured by Fairchild Hiller. Compliance is required as indicated. (a) Before further flight, unless already accomplished, inspect the aileron control cable turnbuckles for safety wires that meet the size and corrosion resistance specifications and the method of safetying specifications of Military Standard 20995C47 and Military Standard 33591, respectively, or FAA-approved equivalents. (b) Within the next 50 hours' time in service after the effective date of this AD or before November 15, 1971, whichever occurs sooner, inspect the rudder, elevator, and flap control cables turnbuckles for safety wires that meet the size and corrosion resistance specifications of Military Standard 20995C47 and Military Standard 33591, respectively, or FAA-approved equivalent. (c) If turnbuckle safety wires are found that do not meet the size or corrosion resistance specifications or the method of safetying specifications of Military Standard 20995C47 and Military Standard 33591, respectively, or FAA-approved equivalents, during an inspection required by paragraph (a) or (b), before further flight, except that the airplane may be flown in accordance with FAR 21.197 to a base where the repairs can be performed, replace affected turnbuckle safety wires with safety wires that meet those specifications or FAA-approved equivalents. (d) Within the next 50 hours' time in service after the effective date of this AD or before November 15, 1971, whichever occurs sooner, inspect the rudder and elevator trim cable turnbuckles for safety wires that meet the size and corrosion resistance specifications and the method of safetying specifications of Military Standard 20995C32 and Military Standard 33591, respectively, or FAA-approved equivalents. (e) If turnbuckle safety wires are found that do not meet the size or corrosion resistance specifications or the method of safetying specifications of Military Standard 20995C32 and Military Standard 33591, respectively, or FAA-approved equivalents, during an inspection required by paragraph (d), before further flight, except that the airplane may be flown in accordance with FAR 21.197 to a base where the repairs can be performed, replace affected turnbuckle safety wires with safety wires that meet those specifications or FAA-approved equivalents. (Fairchild Hiller Service Letter PC-6-27-2, dated July 20, 1971, refers to this subject). This amendment is effective upon publication in the Federal Register as to all persons except those persons to whom it was made effective immediately upon receipt of the airmail letter dated October 9, 1971, which contained this amendment. FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_71-23-01.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 71-23-01 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Pilatus Model PC-6 Airplanes Subject: Safety of Aileron Cable Turnbuckles Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: Make: Pilatus Aircraft Limited Model: PC-6 | PC-6-H1 | PC-6-H2 | PC-6/350 | PC-6/350-H1 | PC-6/350-H2 | PC-6/A | PC-6/A-H1 | PC-6/A-H2 | P...Show more 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: 71-23-01 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-1326 AD NUMBER: 71-23-01 SUBJECT HEADING: Airworthiness Directives; Pilatus Model PC-6 Airplanes ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 71-23-01 PILATUS AIRCRAFT: Amdt. 39-1326. Applies to Pilatus Model PC-6 (Heli-Porter) airplanes manufactured by Fairchild Hiller. Compliance is required as indicated. (a) Before further flight, unless already accomplished, inspect the aileron control cable turnbuckles for safety wires that meet the size and corrosion resistance specifications and the method of safetying specifications of Military Standard 20995C47 and Military Standard 33591, respectively, or FAA-approved equivalents. (b) Within the next 50 hours' time in service after the effective date of this AD or before November 15, 1971, whichever occurs sooner, inspect the rudder, elevator, and flap control cables turnbuckles for safety wires that meet the size and corrosion resistance specifications of Military Standard 20995C47 and Military Standard 33591, respectively, or FAA-approved equivalent. (c) If turnbuckle safety wires are found that do not meet the size or corrosion resistance specifications or the method of safetying specifications of Military Standard 20995C47 and Military Standard 33591, respectively, or FAA-approved equivalents, during an inspection required by paragraph (a) or (b), before further flight, except that the airplane may be flown in accordance with FAR 21.197 to a base where the repairs can be performed, replace affected turnbuckle safety wires with safety wires that meet those specifications or FAA-approved equivalents. (d) Within the next 50 hours' time in service after the effective date of this AD or before November 15, 1971, whichever occurs sooner, inspect the rudder and elevator trim cable turnbuckles for safety wires that meet the size and corrosion resistance specifications and the method of safetying specifications of Military Standard 20995C32 and Military Standard 33591, respectively, or FAA-approved equivalents. (e) If turnbuckle safety wires are found that do not meet the size or corrosion resistance specifications or the method of safetying specifications of Military Standard 20995C32 and Military Standard 33591, respectively, or FAA-approved equivalents, during an inspection required by paragraph (d), before further flight, except that the airplane may be flown in accordance with FAR 21.197 to a base where the repairs can be performed, replace affected turnbuckle safety wires with safety wires that meet those specifications or FAA-approved equivalents. (Fairchild Hiller Service Letter PC-6-27-2, dated July 20, 1971, refers to this subject). This amendment is effective upon publication in the Federal Register as to all persons except those persons to whom it was made effective immediately upon receipt of the airmail letter dated October 9, 1971, which contained this amendment. FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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