AD 73-25-03
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Hiller Aviation | UH-12D | Airworthiness Directives; Hiller Model UH-12D Helicopters |
Unsafe Condition
Finite life components may exceed their service life limits, leading to failure or malfunction.
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Required Actions
Replace the finite life components listed in Hiller Aviation's UH-12D Inspection Guide, Airworthiness Limitations Section, dated November 5, 1973, with new or serviceable parts at the times specified therein.
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Compliance Time
Prior to further flight for helicopters converted from the military version (H-23D) before the effective date of this AD, and at the time of conversion for those converted after the effective date.
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Affected Aircraft
Hiller Aviation Model UH-12D helicopters certificated in all categories, including those converted from the military version (H-23D).
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Federal Register Abstract
Finite Life Components
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_73-25-03.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 73-25-03 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Hiller Model UH-12D Helicopters Subject: Finite Life Components Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 01/10/1974 Make: Hiller Aviation Model: UH-12D Product Type: Aircraft Product Subtype: Rotorcraft Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 73-25-03 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-1752 AD NUMBER: 73-25-03 SUBJECT HEADING: Airworthiness Directives; Hiller Model UH-12D Helicopters ACTION: SUMMARY: DATES: Effective January 10, 1974. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 73-25-03 HILLER AVIATION: Amdt. 39-1752. Applies to Hiller UH-12D helicopters certificated in all categories. Compliance required prior to further flight for all UH-12D helicopters which have been converted from the military version (H-23D) before the effective date of this AD, and at the time of conversion for those helicopters which are converted to the UH-12D after the effective date of this AD. To insure safe service life for the finite life components of the Hiller Model UH-12D Helicopters, accomplish the following: Replace the finite life components listed in Hiller Aviation's UH-12D Inspection Guide, Airworthiness Limitations Section, dated November 5, 1973, at the times specified therein with new or serviceable parts. NOTE: A copy of the finite life components list can be obtained from Hiller Aviation, 2075 West Scranton Avenue, Porterville, California, 93257, or from the FAA, Aircraft Engineering Division, P. O. Box 92007, World Way Postal Center, Los Angeles, California 90009. This amendment becomes effective January 10, 1974. FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_73-25-03.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 73-25-03 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Hiller Model UH-12D Helicopters Subject: Finite Life Components Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 01/10/1974 Make: Hiller Aviation Model: UH-12D Product Type: Aircraft Product Subtype: Rotorcraft Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 73-25-03 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-1752 AD NUMBER: 73-25-03 SUBJECT HEADING: Airworthiness Directives; Hiller Model UH-12D Helicopters ACTION: SUMMARY: DATES: Effective January 10, 1974. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 73-25-03 HILLER AVIATION: Amdt. 39-1752. Applies to Hiller UH-12D helicopters certificated in all categories. Compliance required prior to further flight for all UH-12D helicopters which have been converted from the military version (H-23D) before the effective date of this AD, and at the time of conversion for those helicopters which are converted to the UH-12D after the effective date of this AD. To insure safe service life for the finite life components of the Hiller Model UH-12D Helicopters, accomplish the following: Replace the finite life components listed in Hiller Aviation's UH-12D Inspection Guide, Airworthiness Limitations Section, dated November 5, 1973, at the times specified therein with new or serviceable parts. NOTE: A copy of the finite life components list can be obtained from Hiller Aviation, 2075 West Scranton Avenue, Porterville, California, 93257, or from the FAA, Aircraft Engineering Division, P. O. Box 92007, World Way Postal Center, Los Angeles, California 90009. This amendment becomes effective January 10, 1974. FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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