AD 49-06-04
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Aero Spacelines, Incorporated | 377 | BOEING Model 377 Aircraft |
| aircraft | Aero Spacelines, Incorporated | 377MG | BOEING Model 377 Aircraft |
| aircraft | Aero Spacelines, Incorporated | 377SGT | BOEING Model 377 Aircraft |
Unsafe Condition
The 11 convolution type altitude compensating bellows (Bendix P/N 390935) may fail due to fatigue after 100 hours of operation.
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Required Actions
Replace the 11 convolution type altitude compensating bellows (Bendix P/N 390935) with new bellows after each 100 hours of operation until the 9 convolution type Bendix P/N 391003 is installed in the carburetor.
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Compliance Time
after each 100 hours of operation
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Affected Aircraft
BOEING Model 377 Aircraft
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Federal Register Abstract
Altitude Compensating Bellows
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_49-06-04.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 49-06-04 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: BOEING Model 377 Aircraft Subject: Altitude Compensating Bellows Status: Current Citation: This information is not available. Citation Publish Date: 06/17/1950 Effective Date: Make: Aero Spacelines, Incorporated Model: 377 | 377MG | 377SGT Product Type: Aircraft Product Subtype: Large Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: AIR-700: Compliance & Airworthiness Division Office of Primary Responsibility: AIR-720: Operational Safety Branch CFR Part Reference: Part 39 Comments: unable to find issue date AIRWORTHINESS DIRECTIVES FINAL RULES: 49-06-04 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 49-06-04 SUBJECT HEADING: BOEING Model 377 Aircraft ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 49-06-04 BOEING: Applies to Model 377 Aircraft. The 11 convolution type altitude compensating bellows, Bendix P/N 390935, shall be replaced with new bellows after each 100 hours of operation until the 9 convolution type Bendix P/N 391003 is available and has been installed in the carburetor. FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_49-06-04.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 49-06-04 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: BOEING Model 377 Aircraft Subject: Altitude Compensating Bellows Status: Current Citation: This information is not available. Citation Publish Date: 06/17/1950 Effective Date: Make: Aero Spacelines, Incorporated Model: 377 | 377MG | 377SGT Product Type: Aircraft Product Subtype: Large Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: AIR-700: Compliance & Airworthiness Division Office of Primary Responsibility: AIR-720: Operational Safety Branch CFR Part Reference: Part 39 Comments: unable to find issue date AIRWORTHINESS DIRECTIVES FINAL RULES: 49-06-04 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 49-06-04 SUBJECT HEADING: BOEING Model 377 Aircraft ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 49-06-04 BOEING: Applies to Model 377 Aircraft. The 11 convolution type altitude compensating bellows, Bendix P/N 390935, shall be replaced with new bellows after each 100 hours of operation until the 9 convolution type Bendix P/N 391003 is available and has been installed in the carburetor. FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
This site is not affiliated with or endorsed by the FAA. Always verify with official sources.
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