AD 88-03-09
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | The Boeing Company | DC-9-81 (MD-81) | Airworthiness Directives; MCDONNELL DOUGLAS DC-9-81, -82, and -83 Series Airplanes |
| aircraft | The Boeing Company | DC-9-82 (MD-82) | Airworthiness Directives; MCDONNELL DOUGLAS DC-9-81, -82, and -83 Series Airplanes |
| aircraft | The Boeing Company | DC-9-83 (MD-83) | Airworthiness Directives; MCDONNELL DOUGLAS DC-9-81, -82, and -83 Series Airplanes |
Unsafe Condition
Erroneous information transmission from the Digital Air Data Computer (DADC) to the Digital Flight Guidance Computer (DFGC) due to electrical transients.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Inspect Honeywell P/N HG280D80 DADC to determine if Modification 8 is installed. If installed but not identified, identify it per service bulletin. If not installed, modify and identify the DADC as per service bulletin. Alternate means of compliance may be approved.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Within 12 months after the effective date of this airworthiness directive (March 11, 1988).
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
McDonnell Douglas Model DC-9-81, -82, and -83 series airplanes listed in McDonnell Douglas Service Bulletin 34-177, dated April 28, 1987.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Digital Flight Guidance Computer
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_88-03-09.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 88-03-09 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; MCDONNELL DOUGLAS DC-9-81, -82, and -83 Series Airplanes Subject: Digital Flight Guidance Computer Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 03/11/1988 Make: The Boeing Company Model: DC-9-81 (MD-81) | DC-9-82 (MD-82) | DC-9-83 (MD-83) Product Type: Aircraft Product Subtype: Large Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 88-03-09 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-5839 AD NUMBER: 88-03-09 SUBJECT HEADING: Airworthiness Directives; MCDONNELL DOUGLAS DC-9-81, -82, and -83 Series Airplanes ACTION: SUMMARY: DATES: Effective March 11, 1988. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 88-03-09 MCDONNELL DOUGLAS: Amendment 39-5839. Applies to McDonnell Douglas Model DC-9-81, -82, and -83 series airplanes, as listed in McDonnell Douglas Service Bulletin 34-177, dated April 28, 1987, certificated in any category. Compliance required as indicated, unless previously accomplished. To prevent erroneous information from being transmitted to the Digital Flight Guidance Computer (DFGC) from the Digital Air Data computer (DADC) in the event of an electrical transient, accomplish the following: A. Within 12 months after the effective date of this airworthiness directive (AD), inspect Honeywell P/N HG280D80 DADC in affected airplanes to determine if Modification 8 has been installed, in accordance with Part 2 of the Accomplishment Instructions of McDonnell Douglas Service Bulletin 34-177, dated April 28, 1987, or later revisions approved by the Manager, Los Angeles Aircraft Certification Office, FAA, Northwest Mountain Region. 1. If Modification 8 has been installed and identified, no further action is necessary. 2. If Modification 8 has been installed but not identified, identify the DADC in accordance with the service bulletin. 3. If Modification 8 has not been installed, modify and identify the DADC in accordance with the service bulletin. B. Alternate means of compliance which provide an acceptable level of safety may be used when approved by the Manager, Los Angeles 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 in order to comply with the requirements of this AD. All persons affected by this directive who have not already received the appropriate service information from the manufacturer may obtain copies upon request to McDonnell Douglas Corporation, 3855 Lakewood Boulevard, Long Beach, California 90846, Attention: Director of Publications, C1-L00 (54-60); or Honeywell, Incorporated, Commercial Aviation Division Technical Services, Mail Station MN23-6345, P.O. Box 889, Minneapolis, Minnesota 55440. These documents may be examined at the FAA, Northwest Mountain Region, 17900 Pacific Highway South, Seattle, Washington, or the Los Angeles Aircraft certification Office, 4344 Donald Douglas Drive, Long Beach, California. This Amendment becomes effective March 11, 1988. FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_88-03-09.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 88-03-09 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; MCDONNELL DOUGLAS DC-9-81, -82, and -83 Series Airplanes Subject: Digital Flight Guidance Computer Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 03/11/1988 Make: The Boeing Company Model: DC-9-81 (MD-81) | DC-9-82 (MD-82) | DC-9-83 (MD-83) 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: 88-03-09 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-5839 AD NUMBER: 88-03-09 SUBJECT HEADING: Airworthiness Directives; MCDONNELL DOUGLAS DC-9-81, -82, and -83 Series Airplanes ACTION: SUMMARY: DATES: Effective March 11, 1988. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 88-03-09 MCDONNELL DOUGLAS: Amendment 39-5839. Applies to McDonnell Douglas Model DC-9-81, -82, and -83 series airplanes, as listed in McDonnell Douglas Service Bulletin 34-177, dated April 28, 1987, certificated in any category. Compliance required as indicated, unless previously accomplished. To prevent erroneous information from being transmitted to the Digital Flight Guidance Computer (DFGC) from the Digital Air Data computer (DADC) in the event of an electrical transient, accomplish the following: A. Within 12 months after the effective date of this airworthiness directive (AD), inspect Honeywell P/N HG280D80 DADC in affected airplanes to determine if Modification 8 has been installed, in accordance with Part 2 of the Accomplishment Instructions of McDonnell Douglas Service Bulletin 34-177, dated April 28, 1987, or later revisions approved by the Manager, Los Angeles Aircraft Certification Office, FAA, Northwest Mountain Region. 1. If Modification 8 has been installed and identified, no further action is necessary. 2. If Modification 8 has been installed but not identified, identify the DADC in accordance with the service bulletin. 3. If Modification 8 has not been installed, modify and identify the DADC in accordance with the service bulletin. B. Alternate means of compliance which provide an acceptable level of safety may be used when approved by the Manager, Los Angeles 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 in order to comply with the requirements of this AD. All persons affected by this directive who have not already received the appropriate service information from the manufacturer may obtain copies upon request to McDonnell Douglas Corporation, 3855 Lakewood Boulevard, Long Beach, California 90846, Attention: Director of Publications, C1-L00 (54-60); or Honeywell, Incorporated, Commercial Aviation Division Technical Services, Mail Station MN23-6345, P.O. Box 889, Minneapolis, Minnesota 55440. These documents may be examined at the FAA, Northwest Mountain Region, 17900 Pacific Highway South, Seattle, Washington, or the Los Angeles Aircraft certification Office, 4344 Donald Douglas Drive, Long Beach, California. This Amendment becomes effective March 11, 1988. FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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