Stinson Aircraft

Stinson Aircraft Company - Comprehensive Manufacturer Profile

Company Overview

Stinson Aircraft Company, founded by aviation pioneer Eddie Stinson in the 1920s, stands as one of America's most significant general aviation manufacturers. Operating primarily from Detroit/Wayne, Michigan, Stinson produced more aircraft than any other Michigan airframe manufacturer of its era, establishing a legacy of combining luxury, reliability, and innovative engineering in cabin aircraft design.

Corporate Evolution and Ownership Timeline

The company underwent several ownership transitions that shaped its development:

• 1920s–1929: Independent operation under Eddie Stinson
• 1929–1934: Cord Corporation ownership
• 1934–1939: AVCO (Aviation Corporation) control
• 1939–1943: Vultee Aircraft integration
• 1943–1948: Convair (Consolidated Vultee) ownership
• 1948: Final acquisition by Piper Aircraft, ending independent Stinson production

Production Summary - Complete Model Lineup

High-Volume Production Models

Reliant Series (SR-Series "Gullwing" Aircraft)

The iconic Stinson Reliant series, known for distinctive gullwing design and radial engines, included multiple variants:

• SR-1 through SR-10: Various models with significant 1930s production
• SR-7, SR-8: Popular executive/utility variants
• SR-9/SR-10: Frequently listed in vintage aircraft registries
• V-77 Gullwing: 1940s-era cabin variant with 300+ hp engines, active in warbird market
• AT-19: WWII military trainer variant of the Reliant

Current Status: Airworthy - Active in vintage aircraft market, high-end warbird community

Complete Model Registry

Additional Production Models:

• Stinson Airliner
• Stinson Detroiter / SB-1 Detroiter
• Stinson Junior
• Stinson L-13 (military)
• Stinson Model A (Trimotor - pre-war airliner)
• Stinson Model O
• Stinson Model R
• Stinson L-1 Vigilant (military observation)
• Stinson 10A, 150 (Voyager variants)
• Stinson HW-75
• Stinson OY-1 Sentinel (Navy variant)

Technical Documentation Framework

Primary Type Certificates and Regulatory Foundation

Type Certificate Data Sheet A-767 - Covers the Stinson 108 series, the company's most successful civilian model. This TCDS remains the primary authority for:

• Approved engines and propellers
• Equipment specifications
• Weight and balance limitations
• Airworthiness requirements

Available Documentation Categories

1. Factory Original Manuals

• Flight Manuals / Pilot Operating Handbooks
• Maintenance and Service Manuals
• Illustrated Parts Catalogs
• Type Specifications and Engineering Reports

2. Univair Technical Reference Library (Stinson 108 Series)

Comprehensive supplementary documentation including:

• Production Information: 90-page serial number database covering complete 108 series production history
• STC List: 10-page summary of FAA Supplementary Type Certificates for TC A-767
• Data Plate Part Numbers: Reference for Stinson 108 series identification
• Attach Hardware Lists: Complete hardware specifications
• Control Cables: Reference chart for 108 series control cable systems
• Control Surface Balance Weight Information: Technical specifications
• Hardware by Part Number or System: Complete aircraft hardware per parts manual
• Operating Limitations: FAA-approved Appendix A to CAA Operating Limitations (108 Landplane, 108-1 Landplane, 108/108-1 Seaplane)
• Axle Nuts: Corrections to parts manual specifications

3. Supplemental Type Certificates (STCs)

Documented aftermarket modifications for active aircraft include:

• Fabric-to-metal wing conversions (108 series)
• Edo 249-2870 float installations
• Engine replacements (Lycoming O-360 conversions from original Franklin 165 hp)
• Various performance and utility upgrades

4. Service Bulletins and Airworthiness Directives

Ongoing technical support documentation for airworthy fleet maintenance and compliance

Stinson 108 Series - Flagship Model Deep Dive

Variant Breakdown and Technical Specifications

Construction and Engineering Details

Airframe:

• Steel tube fuselage structure
• Fabric covering (original specification)
• Later STC modifications: Alclad aluminum skin conversions available
• High-wing configuration for utility and visibility

Powerplant:

• Standard: Franklin 165 hp engines
• STC alternatives: Lycoming O-360 conversions documented

Instrumentation:

• Venturi vacuum systems for flight instruments (standard on most variants)
• Individual aircraft-specific equipment per 1947 AFM specifications

Production Records - Serial Number Database

The comprehensive 90-page production document provides:

• Complete serial number registry for all 5,260+ aircraft
• Variant identification by serial number range
• Production dates and delivery information
• Critical reference for restoration authentication and ownership verification

Current Market Context (2025–2026)

Airworthy Fleet Status

Approximately 3,000 Stinson aircraft remain in active service, with the following models most commonly registered:

Active in Private Ownership:

• Stinson 108 Voyager series (largest active fleet)
• Stinson V-77 Gullwing (high-end warbird market)
• Stinson L-5 Sentinel (warbird/historical aviation community)
• Stinson SR-9/SR-10 Reliant (vintage aircraft enthusiasts)
• Stinson 105 Voyager (limited but active)
• Stinson HW-75 (specialty registrations)

Museum and Historical Preservation:

• Stinson L-5G Sentinel: Maintained in flying status at Planes of Fame Air Museum
• Stinson 1936 SR-9B Reliant: Featured in vintage aircraft displays
• Texas Air Museum – Stinson Chapter (San Antonio): Active preservation venue

Market Trends and Valuation

2025–2026 Market Dynamics:

• Private aircraft market growth: $29.87 billion (2025) → $31.9 billion (2026)
• Pricing stabilization after 2021–2022 appreciation period
• Increased demand for vintage training and utility aircraft
• Strong restoration and parts market supporting active fleet

Active Sales Channels:

• Controller.com: V-77 and 108 models regularly listed
• Airport-Data.com: Production and registration databases
• Aviation Fanatic: Registered Voyagers, 105s, HW-75s
• FAA N-number registry: Current airworthiness verification

Restoration and Maintenance Ecosystem

Active Support Infrastructure:

• Univair Aircraft Corporation: Primary parts supplier and technical documentation provider
• Essco Aircraft: Documentation reproduction and technical support
• Type Clubs and Communities: Active Stinson owner organizations
• Commemorative Air Force: L-5 Sentinel restoration conferences and technical support
• European Restoration Community: Active L-5 Sentinel rebuilds and maintenance

Common Restoration Challenges:

• Sourcing original-specification parts for 1940s-era aircraft
• Fabric-to-metal wing conversions (STC compliance)
• Authentic paint codes and military markings (L-5 Sentinel)
• Multi-aircraft rebuilds (combining salvage airframes)

Regulatory and Airworthiness Framework

FAA Modernization (Effective July 2026)

New specialized airworthiness certification rules will impact vintage aircraft like Stinson models, requiring updated compliance documentation and potentially affecting restoration standards.

Current Type Certificate Holders

Following Piper Aircraft's 1948 acquisition of Stinson, Type Certificate responsibilities transferred through subsequent corporate changes. Current TC holders maintain authority for:

• Airworthiness Directives (ADs)
• Service Bulletin issuance
• STC approval coordination
• Parts Manufacturing Approval (PMA) oversight

International Registry Considerations

Stinson aircraft remain registered in multiple national aviation authorities:

• FAA (United States) - Largest active fleet
• EASA member states (Europe) - Active L-5 and Reliant populations
• Transport Canada - Historical registrations
• Various international registries for museum and private aircraft

Engineering Standards and Manufacturing Practices

Certification Basis

Stinson aircraft were certificated under:

• CAR 3 (Civil Air Regulations Part 3) - Normal category aircraft
• CAR 4A - Small aircraft certification standards
• Military Specifications: L-5 Sentinel, L-1 Vigilant, AT-19 variants

Manufacturing Quality and Design Philosophy

Stinson's Engineering Approach:

• Emphasis on cabin comfort and "luxury" appointments (unusual for 1930s–1940s light aircraft)
• Robust steel tube construction for utility and durability
• High-wing configuration for visibility and ground clearance
• Radial engine integration (Reliant series) for reliability and power

Production Capabilities:

• Peak production: 5,260+ Model 108s in six-year period (1944–1950)
• Wartime production: 3,896+ L-5 Sentinels (1941–1945)
• Consistent quality control through multiple ownership transitions

Legacy and Historical Significance

Industry Impact

Stinson's Contributions to General Aviation:

• Pioneered comfortable cabin aircraft design in the 1930s
• Demonstrated viability of post-war personal aircraft market (108 Voyager success)
• Established high-wing utility aircraft configuration standards
• Influenced subsequent Piper Aircraft designs after 1948 acquisition

Current Preservation Efforts

Documentation Preservation:

• Univair Resource Library: Comprehensive digital archive
• Online Aviation Library: Structured collections with lifetime updates
• Museum archives: Original factory documentation preservation
• Type club repositories: Owner-maintained technical libraries

Physical Aircraft Preservation:

• ~3,000 aircraft in active airworthy status
• Museum collections maintaining flying examples
• Active restoration community ensuring long-term survival
• International registry presence demonstrating global appreciation

Where to Find Additional Information

Official Documentation Sources

Current Type Certificate Holders:

• Contact for current ADs, Service Bulletins, and airworthiness compliance

Univair Aircraft Corporation:

• Parts supplier and technical documentation provider
• Resource Library with comprehensive Stinson 108 references

Essco Aircraft:

• Documentation reproduction services
• Historical manual archives

Community and Historical Resources

Type Clubs and Owner Organizations:

• Stinson owner groups and forums
• Technical support networks
• Restoration expertise sharing

Museums and Historical Societies:

• Texas Air Museum – Stinson Chapter (San Antonio)
• Planes of Fame Air Museum (flying L-5 Sentinel)
• Commemorative Air Force (L-5 restoration programs)

Online Registries and Databases:

• FAA N-number lookup (US registrations)
• Airport-Data.com (production and registration data)
• Aviation Fanatic (international registry tracking)
• Controller.com (current market listings)

Specialty Documentation Providers

Online Aviation Library:

• Structured digital collections for Stinson 108, 105/150, and SR/AT-19 Reliant
• Definitive collections with free lifetime updates
• Organized folder hierarchy and curated indexing
• Professional-grade archival resources for restoration and research

Conclusion

Stinson Aircraft Company's legacy endures through thousands of airworthy aircraft, comprehensive documentation archives, and an active restoration community. From the iconic gullwing Reliants of the 1930s to the ubiquitous 108 Voyager that defined post-war personal aviation, Stinson's engineering excellence and manufacturing quality continue to serve pilots, restorers, and researchers nearly 80 years after the company's absorption by Piper Aircraft.

The availability of detailed technical documentation—from original factory manuals to modern STC modifications—ensures that Stinson aircraft will remain viable and airworthy for generations to come, preserving an essential chapter of American aviation history.