AD 80-18-05
final rule
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Sperry Flight Systems | Flight Director Systems | Airworthiness Directives; SPERRY FLIGHT SYSTEMS, AVIONICS DIVISION: Applies to Flight Director Systems installed on aircraft certified in all categories |
| appliance | Sperry Flight Systems | Flight Director Systems | Airworthiness Directives; SPERRY FLIGHT SYSTEMS, AVIONICS DIVISION: Applies to Flight Director Systems installed on aircraft certified in all categories |
Unsafe Condition
Possible erroneous presentation of glide slope information due to incorrect +28V bias voltage connection into receptacle J1-b on Sperry HSI RD 044 or RD 444.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Revise the circuit hook-up to move the +28V dc bias voltage source from the Flight Director Circuit Breaker to the +28V dc circuit breaker supplying the glide slope receiver. Special flight permits may be issued under FAR 21.197 and 21.199 to operate to a base for modification. Alternative actions providing equivalent safety may be approved by the FAA.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Within the next 100 hours' time in service from the effective date of this AD, or within 60 days from the effective date of this AD, whichever occurs sooner
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Affected Aircraft
Flight Director Systems (STARS) installed on aircraft certified in all categories, including Sperry HSI RD 044 (P/N 2592920-44) and RD 444 (P/N 2592920-444). Beech Model 90, 100, and 200 aircraft with STARS installations are specifically referenced.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Flight Director Systems
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_80-18-05.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 80-18-05 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; SPERRY FLIGHT SYSTEMS, AVIONICS DIVISION: Applies to Flight Director Sys...Show more Subject: Flight Director Systems Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 09/29/1980 Make: Sperry Flight Systems Model: Flight Director Systems Product Type: Appliance 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: 80-18-05 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-3896 AD NUMBER: 80-18-05 SUBJECT HEADING: Airworthiness Directives; SPERRY FLIGHT SYSTEMS, AVIONICS DIVISION: Applies to Flight Director Systems installed on aircraft certified in all categories ACTION: SUMMARY: DATES: Effective September 29, 1980. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 80-18-05 SPERRY FLIGHT SYSTEMS, AVIONICS DIVISION: Amendment 39-3896. Applies to the STARS, (Sperry Three Axis Reference systems), Flight Director Systems installed on aircraft certified in all categories. Compliance is required as indicated, unless already accomplished. To prevent possible erroneous presentation of glide slope information, accomplish the following: (a) Within the next 100 hours' time in service from the effective date of this AD, or within 60 days from the effective date of this AD, whichever occurs sooner, revise the circuit hook-up so that the +28V bias voltage into receptacle J1-b, on the Sperry HSI RD 044 (P/N 2592920-44), RD 444 (P/N 2592920-444) is moved from the +28V dc source, (usually the Flight Director Circuit Breaker), to the +28V dc circuit breaker supplying the glide slope receiver. NOTE: Sperry Flight Systems Division, Maintenance Manual for STARS Flight Director Instrument System, Pub. No. 15-3321-01 dated 30 November 1969, revised 20 February 1980, shows proper connections. NOTE: Sperry Flight Systems Technical Newsletter 23-1979-02, Revision 1, dated March 20, 1979, and Revision 2 dated July 11, 1980 refer to this subject. Revision 2 was published to correct typographical error in Revision 1 issue date. The technical content is not changed. NOTE: Beech Aircraft Corporation letter 900 380-281 dated 19 March 1980 refers to STARS installation in Beech Model 90, 100 and 200 aircraft. (b) 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 modifications required by this AD. (c) Alternative inspections, modifications or other actions which provide an equivalent level of safety may be used when approved by the Chief, Aircraft Engineering Division, FAA Western Region. This amendment becomes effective September 29, 1980. FOOTER:
Document Text
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AD Final Rules - DRS_80-18-05.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 80-18-05 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; SPERRY FLIGHT SYSTEMS, AVIONICS DIVISION: Applies to Flight Director Sys...Show more Subject: Flight Director Systems Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 09/29/1980 Make: Sperry Flight Systems Model: Flight Director Systems Product Type: Appliance 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: 80-18-05 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-3896 AD NUMBER: 80-18-05 SUBJECT HEADING: Airworthiness Directives; SPERRY FLIGHT SYSTEMS, AVIONICS DIVISION: Applies to Flight Director Systems installed on aircraft certified in all categories ACTION: SUMMARY: DATES: Effective September 29, 1980. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 80-18-05 SPERRY FLIGHT SYSTEMS, AVIONICS DIVISION: Amendment 39-3896. Applies to the STARS, (Sperry Three Axis Reference systems), Flight Director Systems installed on aircraft certified in all categories. Compliance is required as indicated, unless already accomplished. To prevent possible erroneous presentation of glide slope information, accomplish the following: (a) Within the next 100 hours' time in service from the effective date of this AD, or within 60 days from the effective date of this AD, whichever occurs sooner, revise the circuit hook-up so that the +28V bias voltage into receptacle J1-b, on the Sperry HSI RD 044 (P/N 2592920-44), RD 444 (P/N 2592920-444) is moved from the +28V dc source, (usually the Flight Director Circuit Breaker), to the +28V dc circuit breaker supplying the glide slope receiver. NOTE: Sperry Flight Systems Division, Maintenance Manual for STARS Flight Director Instrument System, Pub. No. 15-3321-01 dated 30 November 1969, revised 20 February 1980, shows proper connections. NOTE: Sperry Flight Systems Technical Newsletter 23-1979-02, Revision 1, dated March 20, 1979, and Revision 2 dated July 11, 1980 refer to this subject. Revision 2 was published to correct typographical error in Revision 1 issue date. The technical content is not changed. NOTE: Beech Aircraft Corporation letter 900 380-281 dated 19 March 1980 refers to STARS installation in Beech Model 90, 100 and 200 aircraft. (b) 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 modifications required by this AD. (c) Alternative inspections, modifications or other actions which provide an equivalent level of safety may be used when approved by the Chief, Aircraft Engineering Division, FAA Western Region. This amendment becomes effective September 29, 1980. FOOTER:
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