AD 71-23-01

final rule

Airworthiness Directives; Pilatus Model PC-6 Airplanes

AD Number
71-23-01
Status
final_rule
Effective Date
Product Category
aircraft
Docket
Unknown
FR Citation
This information is not available.
Technical illustration of an aircraft flight control surface and actuator
Problem area Flight controls

Applicability

TypeManufacturerModelDetails
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

This site is not affiliated with or endorsed by the FAA. Always verify with official sources.