AD 74-14-01

final rule

HARTZELL PROPELLERS Models T10173H()+(), T10176H()+(), T10178H()-(), and ()T10282H()+(), HC-B3TN-2( ), HC- B3TN-3( ), HC-B3TN-5( ), HC-B3TN-7( ), HC-B3TF-7( ), HC-B4TN-3( ) and HC-B4TN-5( ) Propellers

AD Number
74-14-01
Status
final_rule
Effective Date
Product Category
propeller
Docket
Unknown
FR Citation
This information is not available.
Technical illustration of an aircraft propeller assembly
Problem area Propeller

Applicability

TypeManufacturerModelDetails
aircraft Hartzell Propeller, Inc. HC-B3T HARTZELL PROPELLERS Models T10173H()+(), T10176H()+(), T10178H()-(), and ()T10282H()+(), HC-B3TN-2( ), HC- B3TN-3( ), HC-B3TN-5( ), HC-B3TN-7( ), HC-B3TF-7( ), HC-B4TN-3( ) and HC-B4TN-5( ) Propellers
aircraft Hartzell Propeller, Inc. HC-B4TN-3 HARTZELL PROPELLERS Models T10173H()+(), T10176H()+(), T10178H()-(), and ()T10282H()+(), HC-B3TN-2( ), HC- B3TN-3( ), HC-B3TN-5( ), HC-B3TN-7( ), HC-B3TF-7( ), HC-B4TN-3( ) and HC-B4TN-5( ) Propellers
aircraft Hartzell Propeller, Inc. HC-B4TN-5 HARTZELL PROPELLERS Models T10173H()+(), T10176H()+(), T10178H()-(), and ()T10282H()+(), HC-B3TN-2( ), HC- B3TN-3( ), HC-B3TN-5( ), HC-B3TN-7( ), HC-B3TF-7( ), HC-B4TN-3( ) and HC-B4TN-5( ) Propellers
propeller Hartzell Propeller, Inc. HC-B3T HARTZELL PROPELLERS Models T10173H()+(), T10176H()+(), T10178H()-(), and ()T10282H()+(), HC-B3TN-2( ), HC- B3TN-3( ), HC-B3TN-5( ), HC-B3TN-7( ), HC-B3TF-7( ), HC-B4TN-3( ) and HC-B4TN-5( ) Propellers
propeller Hartzell Propeller, Inc. HC-B4TN-3 HARTZELL PROPELLERS Models T10173H()+(), T10176H()+(), T10178H()-(), and ()T10282H()+(), HC-B3TN-2( ), HC- B3TN-3( ), HC-B3TN-5( ), HC-B3TN-7( ), HC-B3TF-7( ), HC-B4TN-3( ) and HC-B4TN-5( ) Propellers
propeller Hartzell Propeller, Inc. HC-B4TN-5 HARTZELL PROPELLERS Models T10173H()+(), T10176H()+(), T10178H()-(), and ()T10282H()+(), HC-B3TN-2( ), HC- B3TN-3( ), HC-B3TN-5( ), HC-B3TN-7( ), HC-B3TF-7( ), HC-B4TN-3( ) and HC-B4TN-5( ) Propellers

Unsafe Condition

Blade cracks and defects in Hartzell propellers could lead to blade failures.

AI-generated summary from the source AD text. Verify against the official source before acting.

Required Actions

Inspect blades for cracks or defects per Hartzell Bulletin No. 105 or equivalent procedure. Replace cracked or defective blades before further flight with compliant blades or those inspected and found satisfactory.

AI-generated summary from the source AD text. Verify against the official source before acting.

Compliance Time

Within the next 50 hours time in service for propellers with less than 950 hours, prior to 1000 hours in service for those between 950-1000 hours, or as adjusted by FAA approval.

AI-generated summary from the source AD text. Verify against the official source before acting.

Affected Aircraft

Hartzell Propeller, Inc. models HC-B3TN-2, HC-B3TN-3, HC-B3TN-5, HC-B3TN-7, HC-B3TF-7, HC-B4TN-3, HC-B4TN-5 propellers with serial numbers below specified thresholds (e.g., HC-B3TN-2 S/N AG-275 and below).

AI-generated summary from the source AD text. Verify against the official source before acting.

Applicability Source Text

Show captured applicability text from the source AD
AD Final Rules - DRS_74-14-01.html
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AD Number:
74-14-01
Document Type:
AD Final Rules
Docket Number:
Unknown
Subject Heading:
HARTZELL PROPELLERS Models T10173H()+(), T10176H()+(), T10178H()-(), and ()T10282H()+(), HC-B3TN-2( ...Show more
Subject:
Status:
Current
Citation:
This information is not available.
Citation Publish Date:
Effective Date:
08/22/1974
Make:
Hartzell Propeller, Inc.
Model:
HC-B3T | HC-B4TN-3 | HC-B4TN-5
Product Type:
Propeller
Product Subtype:
Affected AD:
Superseded AD:
Affected By:
Superseded By:
Service/Office:
Office of Primary Responsibility:
CFR Part Reference:
Part 39
Comments:
AIRWORTHINESS DIRECTIVES FINAL RULES: 74-14-01
CITATION:   This information is not available.

PAGE NUMBER:  

DOCKET NUMBER:   Unknown

AMENDMENT:   39-1924

AD NUMBER:   74-14-01

SUBJECT HEADING:   HARTZELL PROPELLERS Models T10173H()+(), T10176H()+(), T10178H()-(), and ()T10282H()+(), HC-B3TN-2( ), HC- B3TN-3( ), HC-B3TN-5( ), HC-B3TN-7( ), HC-B3TF-7( ), HC-B4TN-3( ) and HC-B4TN-5( ) Propellers

ACTION:  

SUMMARY:  

DATES:   Effective August 22, 1974.

ADDRESSES:  

FOR FURTHER INFORMATION CONTACT:  

SUPPLEMENTARY INFORMATION:  

REGULATORY TEXT:  
74-14-01 HARTZELL PROPELLERS: Amendment 39-1883 as amended by Amendment 39-1924. Applies to Hartzell T10173H()+(), T10176H()+(), T10178H()-(), and () T10282H()+() hard alloy type blades installed on but not limited to Model HC-B3TN-2( ), HC- B3TN-3( ), HC-B3TN-5( ), HC-B3TN-7( ), HC-B3TF-7( ), HC-B4TN-3( ) and HC-B4TN-5( ) propellers which are used on United Aircraft of Canada Limited PT-6A-( ) and AiResearch TPE 331( )-( ) series engines. These propellers are installed on but not limited to Swearingen SA-226 Series, Short SC-7 Series 3, Aero Commander 690 Series and de Havilland DHC-6 300 type aircraft.

Compliance required as indicated, unless already accomplished. Propellers with more than 1000 hours in service, excepting those with replacement blades having less than 1000 hours in service, as of the effective date of this Airworthiness Directive are excluded. Also, the following propellers having the serial numbers listed below are excluded:

PROPELLER MODEL - HC-B3TN-2; S/N - AG-275 and above
PROPELLER MODEL - HC-B3TN-3; S/N - BU-4624 and above
PROPELLER MODEL - HC-B3TN-5: S/N - BV-2210, BV-2213, BV-2214, BV-2216 and above
PROPELLER MODEL - HC-B3TN-7: S/N - CV-7 and above
PROPELLER MODEL - HC-B3TF-7: S/N - EX-3 and above
PROPELLER MODEL - HC-B4TN-3: S/N - EA-255 and above
PROPELLER MODEL - HC-B4TN-5: S/N - CD-62 and above

To detect blade cracks and prevent possible blade failures, accomplish the following:

(a) Propellers with less than 950 hours in service since new as of the effective date of this Airworthiness Directive must be inspected in accordance with Paragraph (e), within the next 50 hours time in service.

(b) Propellers with 950 hours in service, but not more than 1000 hours in service as of the effective date of this Airworthiness Directive must be inspected in accordance with Paragraph (e) prior to the accumulation of 1000 hours in service.

(c) Propellers whose total hours in service are unknown will be assumed to have less than 950 hours in service since new and thus must be inspected in accordance with the requirements of Paragraph (a).

(d) In the event propellers with more than 1000 hours in service are equipped with replacement blades which have less than 1000 hours in service, such propeller blades must be inspected in accordance with the requirements of Paragraphs (a) or (b), as applicable contingent upon the time in service of the replacement blades.

(e) Inspect blades for cracks or defects in accordance with Hartzell Bulletin No. 105 dated May 22, 1974, or later Federal Aviation Administration approved revision, or an equivalent procedure approved by the Chief, Engineering and Manufacturing Branch, Great Lakes Region. Replace any cracked or defective blades before further flight with blades to which this Airworthiness Directive does not apply, or have been inspected in accordance with this Airworthiness Directive and found satisfactory.

(f) Upon request of the operator a Federal Aviation Administration Maintenance Inspector, subject to prior approval of the Chief, Engineering and Manufacturing Branch, Federal Aviation Administration Great Lakes Region, may adjust the compliance time specified in Paragraph (b), if the request contains substantiating data to justify the adjustment for that operator.

Amendment 39-1883 became effective as of July 2, 1974.

This Amendment 39-1924 becomes effective August 22, 1974.

FOOTER:

Document Text

Show stored source text (verify against official source)
AD Final Rules - DRS_74-14-01.html
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Print/Save as PDF
Document Versions
 Feedback
Details
AD Number:
74-14-01
Document Type:
AD Final Rules
Docket Number:
Unknown
Subject Heading:
HARTZELL PROPELLERS Models T10173H()+(), T10176H()+(), T10178H()-(), and ()T10282H()+(), HC-B3TN-2( ...Show more
Subject:
Status:
Current
Citation:
This information is not available.
Citation Publish Date:
Effective Date:
08/22/1974
Make:
Hartzell Propeller, Inc.
Model:
HC-B3T | HC-B4TN-3 | HC-B4TN-5
Product Type:
Propeller
Product Subtype:
Affected AD:
Superseded AD:
Affected By:
Superseded By:
Service/Office:
Office of Primary Responsibility:
CFR Part Reference:
Part 39
Comments:
AIRWORTHINESS DIRECTIVES FINAL RULES: 74-14-01
CITATION:   This information is not available.

PAGE NUMBER:  

DOCKET NUMBER:   Unknown

AMENDMENT:   39-1924

AD NUMBER:   74-14-01

SUBJECT HEADING:   HARTZELL PROPELLERS Models T10173H()+(), T10176H()+(), T10178H()-(), and ()T10282H()+(), HC-B3TN-2( ), HC- B3TN-3( ), HC-B3TN-5( ), HC-B3TN-7( ), HC-B3TF-7( ), HC-B4TN-3( ) and HC-B4TN-5( ) Propellers

ACTION:  

SUMMARY:  

DATES:   Effective August 22, 1974.

ADDRESSES:  

FOR FURTHER INFORMATION CONTACT:  

SUPPLEMENTARY INFORMATION:  

REGULATORY TEXT:  
74-14-01 HARTZELL PROPELLERS: Amendment 39-1883 as amended by Amendment 39-1924. Applies to Hartzell T10173H()+(), T10176H()+(), T10178H()-(), and () T10282H()+() hard alloy type blades installed on but not limited to Model HC-B3TN-2( ), HC- B3TN-3( ), HC-B3TN-5( ), HC-B3TN-7( ), HC-B3TF-7( ), HC-B4TN-3( ) and HC-B4TN-5( ) propellers which are used on United Aircraft of Canada Limited PT-6A-( ) and AiResearch TPE 331( )-( ) series engines. These propellers are installed on but not limited to Swearingen SA-226 Series, Short SC-7 Series 3, Aero Commander 690 Series and de Havilland DHC-6 300 type aircraft.

Compliance required as indicated, unless already accomplished. Propellers with more than 1000 hours in service, excepting those with replacement blades having less than 1000 hours in service, as of the effective date of this Airworthiness Directive are excluded. Also, the following propellers having the serial numbers listed below are excluded:

PROPELLER MODEL - HC-B3TN-2; S/N - AG-275 and above
PROPELLER MODEL - HC-B3TN-3; S/N - BU-4624 and above
PROPELLER MODEL - HC-B3TN-5: S/N - BV-2210, BV-2213, BV-2214, BV-2216 and above
PROPELLER MODEL - HC-B3TN-7: S/N - CV-7 and above
PROPELLER MODEL - HC-B3TF-7: S/N - EX-3 and above
PROPELLER MODEL - HC-B4TN-3: S/N - EA-255 and above
PROPELLER MODEL - HC-B4TN-5: S/N - CD-62 and above

To detect blade cracks and prevent possible blade failures, accomplish the following:

(a) Propellers with less than 950 hours in service since new as of the effective date of this Airworthiness Directive must be inspected in accordance with Paragraph (e), within the next 50 hours time in service.

(b) Propellers with 950 hours in service, but not more than 1000 hours in service as of the effective date of this Airworthiness Directive must be inspected in accordance with Paragraph (e) prior to the accumulation of 1000 hours in service.

(c) Propellers whose total hours in service are unknown will be assumed to have less than 950 hours in service since new and thus must be inspected in accordance with the requirements of Paragraph (a).

(d) In the event propellers with more than 1000 hours in service are equipped with replacement blades which have less than 1000 hours in service, such propeller blades must be inspected in accordance with the requirements of Paragraphs (a) or (b), as applicable contingent upon the time in service of the replacement blades.

(e) Inspect blades for cracks or defects in accordance with Hartzell Bulletin No. 105 dated May 22, 1974, or later Federal Aviation Administration approved revision, or an equivalent procedure approved by the Chief, Engineering and Manufacturing Branch, Great Lakes Region. Replace any cracked or defective blades before further flight with blades to which this Airworthiness Directive does not apply, or have been inspected in accordance with this Airworthiness Directive and found satisfactory.

(f) Upon request of the operator a Federal Aviation Administration Maintenance Inspector, subject to prior approval of the Chief, Engineering and Manufacturing Branch, Federal Aviation Administration Great Lakes Region, may adjust the compliance time specified in Paragraph (b), if the request contains substantiating data to justify the adjustment for that operator.

Amendment 39-1883 became effective as of July 2, 1974.

This Amendment 39-1924 becomes effective August 22, 1974.

FOOTER:

Source: Official FAA Source ↗

Retrieved: Apr 8, 2026

Rights: U.S. Government Public Domain

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