AD 55-15-01
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Aero Spacelines, Incorporated | 377 | BOEING 377 Series Aircraft |
| aircraft | Aero Spacelines, Incorporated | 377MG | BOEING 377 Series Aircraft |
| aircraft | Aero Spacelines, Incorporated | 377SGT | BOEING 377 Series Aircraft |
Unsafe Condition
Flexible hose components of propeller feathering lines forward of the firewall in zone 2 may fail due to insufficient fire resistance, increasing the risk of system damage from a powerplant fire.
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Required Actions
Replace all flexible hose components of propeller feathering lines forward of the firewall in zone 2 with lines and fittings meeting current fire resistance requirements, using acceptable hose assemblies such as Aeroquip 680-10S with protective sleeves, Resistoflex SSFR-3800-10, or Aeroquip 309009-10S.
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Compliance Time
by first scheduled engine change after November 1, 1955, but not later than November 1, 1956
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Affected Aircraft
Aero Spacelines, Incorporated models 377, 377MG, 377SGT with Hamilton Standard Propellers
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Federal Register Abstract
Propeller Feathering Lines
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_55-15-01.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 55-15-01 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: BOEING 377 Series Aircraft Subject: Propeller Feathering Lines Status: Current Citation: This information is not available. Citation Publish Date: 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Incorporated Model: 377 | 377MG | 377SGT Product Type: Aircraft Product Subtype: Large Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 55-15-01 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 55-15-01 SUBJECT HEADING: BOEING 377 Series Aircraft ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 55-15-01 BOEING: Applies to All Boeing 377 Series Aircraft with Hamilton Standard Propellers. Compliance required by first scheduled engine change after November 1, 1955, but not later than November 1, 1956. To increase the fire resistance integrity of the propeller feathering system against damage by a powerplant fire, all flexible hose components of propeller feathering lines forward of the firewall in zone 2 must be replaced with lines and fittings which will meet current fire resistance requirements. The following hose assemblies are considered acceptable for this applications: (a) Aeroquip 680-10S hose assemblies with Aeroquip 304 protective sleeves over end fittings (Aeroquip assembly P/N 304000). (b) Resistoflex SSFR-3800-10 hose assemblies. (c) Aeroquip 309009-10S hose assemblies. FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_55-15-01.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 55-15-01 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: BOEING 377 Series Aircraft Subject: Propeller Feathering Lines Status: Current Citation: This information is not available. Citation Publish Date: 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: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 55-15-01 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 55-15-01 SUBJECT HEADING: BOEING 377 Series Aircraft ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 55-15-01 BOEING: Applies to All Boeing 377 Series Aircraft with Hamilton Standard Propellers. Compliance required by first scheduled engine change after November 1, 1955, but not later than November 1, 1956. To increase the fire resistance integrity of the propeller feathering system against damage by a powerplant fire, all flexible hose components of propeller feathering lines forward of the firewall in zone 2 must be replaced with lines and fittings which will meet current fire resistance requirements. The following hose assemblies are considered acceptable for this applications: (a) Aeroquip 680-10S hose assemblies with Aeroquip 304 protective sleeves over end fittings (Aeroquip assembly P/N 304000). (b) Resistoflex SSFR-3800-10 hose assemblies. (c) Aeroquip 309009-10S hose assemblies. 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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