AD 90-21-20
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Airbus | A320-111 | Airworthiness Directives; AIRBUS INDUSTRIE Model A320-111, A320-211, and A320-231 Series Airplanes |
| aircraft | Airbus | A320-211 | Airworthiness Directives; AIRBUS INDUSTRIE Model A320-111, A320-211, and A320-231 Series Airplanes |
| aircraft | Airbus | A320-231 | Airworthiness Directives; AIRBUS INDUSTRIE Model A320-111, A320-211, and A320-231 Series Airplanes |
Unsafe Condition
Simultaneous activation in flight of two angle of attack sensors could result in an incorrect pitch-down command to the elevator.
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Required Actions
Disconnect and modify wiring in relay box 103VU, Zones 127 and 232 per Airbus Service Bulletin A320-34-1012 (Rev 1/2) or perform Modification No. 21824P1953 by moving test control wires per Service Bulletin A320-34-1013. Alternate means/adjustments require FAA approval.
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Compliance Time
within the next 350 hours time-in-service after the effective date of this AD
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Affected Aircraft
All Model A320-111, A320-211, and A320-231 series airplanes, certificated in any category.
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Federal Register Abstract
Relay box wiring & angle of attack sensors
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_90-21-20.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 90-21-20 Document Type: AD Final Rules Docket Number: 90-NM-91-AD Subject Heading: Airworthiness Directives; AIRBUS INDUSTRIE Model A320-111, A320-211, and A320-231 Series Airplanes Subject: Relay box wiring & angle of attack sensors Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 11/19/1990 Make: Airbus Model: A320-111 | A320-211 | A320-231 Product Type: Aircraft Product Subtype: Large Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 90-21-20 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: 90-NM-91-AD AMENDMENT: 39-6770 AD NUMBER: 90-21-20 SUBJECT HEADING: Airworthiness Directives; AIRBUS INDUSTRIE Model A320-111, A320-211, and A320-231 Series Airplanes ACTION: SUMMARY: DATES: Effective November 19, 1990. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 90-21-20 AIRBUS INDUSTRIE: Amendment 39-6770. Docket No. 90-NM-91-AD. Applicability: All Model A320-111, A320-211, and A320-231 series airplanes, certificated in any category. Compliance: Required within the next 350 hours time-in-service after the effective date of this AD, unless previously accomplished. To prevent the simultaneous activation in flight of two angle of attack sensors and subsequent incorrect pitch-down command to the elevator, accomplish the following: A. Perform one of the following: 1. Disconnect and modify the wiring in the relay box 103VU, in Zone 127, and in Zone 232, in accordance with Airbus Industrie Service Bulletin A320-34-1012, Revision 1, dated April 10, 1990; or Revision 2, dated June 8, 1990; or 2. Accomplish Modification No. 21824P1953, which consists of moving the test control wires of the angle of attack sensors, in accordance with Airbus Industrie Service Bulletin A320-34-1013, dated June 1, 1990. B. An alternate means of compliance or adjustment of the compliance time, which provides an acceptable level of safety, may be used when approved by the Manager, Standardization Branch, ANM-113, FAA, Transport Airplane Directorate. NOTE: The request should be submitted directly to the Manager, Standardization Branch, ANM-113, and a copy sent to the cognizant FAA Principal Inspector (PI). The PI will then forward comments or concurrence to the Manager, Standardization Branch, ANM-113. C. Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate airplanes to a base in order to comply with the requirements of this AD. All persons affected by this directive who have not already received the appropriate service documents from the manufacturer may obtain copies upon request to Airbus Industrie, Airbus Support Division, Avenue Didier Daurat, 31700 Blagnac, France. These documents may be examined at the FAA, Northwest Mountain Region, Transport Airplane Directorate, 1601 Lind Avenue S.W., Renton, Washington. This amendment (39-6770, AD 90-21-20) becomes effective November 19, 1990. FOOTER:
Document Text
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AD Final Rules - DRS_90-21-20.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 90-21-20 Document Type: AD Final Rules Docket Number: 90-NM-91-AD Subject Heading: Airworthiness Directives; AIRBUS INDUSTRIE Model A320-111, A320-211, and A320-231 Series Airplanes Subject: Relay box wiring & angle of attack sensors Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 11/19/1990 Make: Airbus Model: A320-111 | A320-211 | A320-231 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: 90-21-20 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: 90-NM-91-AD AMENDMENT: 39-6770 AD NUMBER: 90-21-20 SUBJECT HEADING: Airworthiness Directives; AIRBUS INDUSTRIE Model A320-111, A320-211, and A320-231 Series Airplanes ACTION: SUMMARY: DATES: Effective November 19, 1990. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 90-21-20 AIRBUS INDUSTRIE: Amendment 39-6770. Docket No. 90-NM-91-AD. Applicability: All Model A320-111, A320-211, and A320-231 series airplanes, certificated in any category. Compliance: Required within the next 350 hours time-in-service after the effective date of this AD, unless previously accomplished. To prevent the simultaneous activation in flight of two angle of attack sensors and subsequent incorrect pitch-down command to the elevator, accomplish the following: A. Perform one of the following: 1. Disconnect and modify the wiring in the relay box 103VU, in Zone 127, and in Zone 232, in accordance with Airbus Industrie Service Bulletin A320-34-1012, Revision 1, dated April 10, 1990; or Revision 2, dated June 8, 1990; or 2. Accomplish Modification No. 21824P1953, which consists of moving the test control wires of the angle of attack sensors, in accordance with Airbus Industrie Service Bulletin A320-34-1013, dated June 1, 1990. B. An alternate means of compliance or adjustment of the compliance time, which provides an acceptable level of safety, may be used when approved by the Manager, Standardization Branch, ANM-113, FAA, Transport Airplane Directorate. NOTE: The request should be submitted directly to the Manager, Standardization Branch, ANM-113, and a copy sent to the cognizant FAA Principal Inspector (PI). The PI will then forward comments or concurrence to the Manager, Standardization Branch, ANM-113. C. Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate airplanes to a base in order to comply with the requirements of this AD. All persons affected by this directive who have not already received the appropriate service documents from the manufacturer may obtain copies upon request to Airbus Industrie, Airbus Support Division, Avenue Didier Daurat, 31700 Blagnac, France. These documents may be examined at the FAA, Northwest Mountain Region, Transport Airplane Directorate, 1601 Lind Avenue S.W., Renton, Washington. This amendment (39-6770, AD 90-21-20) becomes effective November 19, 1990. FOOTER:
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