AD 85-07-08
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | BRITISH | 125 | Airworthiness Directives; BRITISH AEROSPACE Model HS/BH/DH 125 Series Airplanes |
Unsafe Condition
Failure of the audio communication system
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Modify the power supply system in accordance with British Aerospace HS 125 Service Bulletin 23-21-8765. Alternate means of compliance may be used if approved by the FAA. Special flight permits may be issued under FAR 21.197 and 21.199.
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Compliance Time
within 180 days after the effective date of this AD, unless previously accomplished
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Affected Aircraft
BRITISH AEROSPACE Model HS/BH/DH 125 series airplanes with serial numbers listed in Service Bulletin 23-21-8765
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Audio Communication System
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_85-07-08.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 85-07-08 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; BRITISH AEROSPACE Model HS/BH/DH 125 Series Airplanes Subject: Audio Communication System Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 05/13/1985 Make: Model: BH.125 Series 400A | BH.125 Series 600A | DH.125 Series 1A | DH.125 Series 1A/R-522 | DH.125 Series ...Show more Product Type: Aircraft Product Subtype: Large Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 85-07-08 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-5032 AD NUMBER: 85-07-08 SUBJECT HEADING: Airworthiness Directives; BRITISH AEROSPACE Model HS/BH/DH 125 Series Airplanes ACTION: SUMMARY: DATES: Effective May 13, 1985. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 85-07-08 BRITISH AEROSPACE: Amendment 39-5032. Applies to Model HS/BH/DH 125 series airplanes with the serial numbers listed in the applicability statement of British Aerospace HS 125 Service Bulletin 23-21-(8765), dated March 22, 1983. Compliance is required within 180 days after the effective date of this AD, unless previously accomplished. To prevent failure of the audio communication system, accomplish the following: A. Modify the power supply system in accordance with the accomplishment instructions of British Aerospace HS 125 Service Bulletin 23-21-8765, dated March 22, 1983. B. Alternate means of compliance which provide an acceptable level of safety may be used when approved by the Manager, Seattle Aircraft Certification Office, FAA, Northwest Mountain Region. C. Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate airplanes to a base for the accomplishment of inspections and/or modifications required by this AD. This amendment becomes effective May 13, 1985. FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_85-07-08.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 85-07-08 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; BRITISH AEROSPACE Model HS/BH/DH 125 Series Airplanes Subject: Audio Communication System Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 05/13/1985 Make: Model: BH.125 Series 400A | BH.125 Series 600A | DH.125 Series 1A | DH.125 Series 1A/R-522 | DH.125 Series ...Show more Product Type: Aircraft Product Subtype: Large 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: 85-07-08 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-5032 AD NUMBER: 85-07-08 SUBJECT HEADING: Airworthiness Directives; BRITISH AEROSPACE Model HS/BH/DH 125 Series Airplanes ACTION: SUMMARY: DATES: Effective May 13, 1985. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 85-07-08 BRITISH AEROSPACE: Amendment 39-5032. Applies to Model HS/BH/DH 125 series airplanes with the serial numbers listed in the applicability statement of British Aerospace HS 125 Service Bulletin 23-21-(8765), dated March 22, 1983. Compliance is required within 180 days after the effective date of this AD, unless previously accomplished. To prevent failure of the audio communication system, accomplish the following: A. Modify the power supply system in accordance with the accomplishment instructions of British Aerospace HS 125 Service Bulletin 23-21-8765, dated March 22, 1983. B. Alternate means of compliance which provide an acceptable level of safety may be used when approved by the Manager, Seattle Aircraft Certification Office, FAA, Northwest Mountain Region. C. Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate airplanes to a base for the accomplishment of inspections and/or modifications required by this AD. This amendment becomes effective May 13, 1985. FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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