AD 77-21-09
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Lockheed Martin Corporation | 188A | LOCKHEED-CALIFORNIA COMPANY Models 188A and 188C Airplanes |
| aircraft | Lockheed Martin Corporation | 188C | LOCKHEED-CALIFORNIA COMPANY Models 188A and 188C Airplanes |
Unsafe Condition
Jamming of the aileron/rudder balance interconnect mechanism
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Required Actions
Remove the aileron rudder balance interconnect mechanism in accordance with Lockheed Electra Service Bulletin Alert 88/SB-698 or later FAA approved revision.
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Compliance Time
within 100 hours additional time in service after the effective date of this AD
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Affected Aircraft
Lockheed-CALIFORNIA COMPANY Models 188A and 188C airplanes, certificated in all categories
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Federal Register Abstract
Aileron Rudder Balance Interconnect Mechanism
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_77-21-09.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 77-21-09 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: LOCKHEED-CALIFORNIA COMPANY Models 188A and 188C Airplanes Subject: Aileron Rudder Balance Interconnect Mechanism Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 11/25/1977 Make: Lockheed Martin Corporation Model: 188A | 188C Product Type: Aircraft Product Subtype: Large Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 77-21-09 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-3059 AD NUMBER: 77-21-09 SUBJECT HEADING: LOCKHEED-CALIFORNIA COMPANY Models 188A and 188C Airplanes ACTION: SUMMARY: DATES: Effective November 25, 1977. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 77-21-09 LOCKHEED-CALIFORNIA COMPANY: Amendment 39-3059. Applies to Model 188A and 188C airplanes, certificated in all categories. Compliance is required within 100 hours additional time in service after the effective date of this AD, unless already accomplished. To prevent possible jamming of the aileron/rudder remove the aileron rudder balance interconnect mechanism, in accordance with instructions given in Lockheed Electra Service Bulletin Alert 88/SB-698, dated September 12, 1977, or later FAA approved revision. This amendment becomes effective November 25, 1977. FOOTER:
Document Text
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AD Final Rules - DRS_77-21-09.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 77-21-09 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: LOCKHEED-CALIFORNIA COMPANY Models 188A and 188C Airplanes Subject: Aileron Rudder Balance Interconnect Mechanism Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 11/25/1977 Make: Lockheed Martin Corporation Model: 188A | 188C 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: 77-21-09 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-3059 AD NUMBER: 77-21-09 SUBJECT HEADING: LOCKHEED-CALIFORNIA COMPANY Models 188A and 188C Airplanes ACTION: SUMMARY: DATES: Effective November 25, 1977. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 77-21-09 LOCKHEED-CALIFORNIA COMPANY: Amendment 39-3059. Applies to Model 188A and 188C airplanes, certificated in all categories. Compliance is required within 100 hours additional time in service after the effective date of this AD, unless already accomplished. To prevent possible jamming of the aileron/rudder remove the aileron rudder balance interconnect mechanism, in accordance with instructions given in Lockheed Electra Service Bulletin Alert 88/SB-698, dated September 12, 1977, or later FAA approved revision. This amendment becomes effective November 25, 1977. FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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