The Savoia Marchetti S.55 was one of the most remarkable flying boats of the interwar period — a pioneering Italian twin-hull design by Alessandro Marchetti (1923) that set numerous world records for speed, altitude, and payload. This structured collection brings together the essential technical documentation for the S.55 and its variants, organized for serious researchers, restorers, and aviation historians.
Definitive Collection with Free Lifetime Updates: This is a living collection that we continuously expand and refine. As we acquire additional S.55 documentation, technical bulletins, or variant-specific materials, we update this collection and provide free lifetime updates to all purchasers. Your one-time purchase guarantees access to all future additions and improvements to this collection.
Historical Note
Designed by Alessandro Marchetti and first flown in 1923, the Savoia Marchetti S.55 was a revolutionary twin-hull flying boat featuring an innovative "flying wing" configuration in which the pilots and mechanics were housed within the thick center section of the parasol wing. Power was provided by two engines mounted in a tandem push-pull nacelle high above the wing — initially Isotta Fraschini Asso 500 V-12 water-cooled engines (370 kW / 500 hp each), later upgraded to the Isotta Fraschini Asso 750 W-18 (656 kW / 880 hp each) in the definitive S.55X variant.
The S.55 achieved international fame through Italo Balbo's mass formation transatlantic flights of 1930 and 1933, demonstrating extraordinary range and reliability. The S.55X variant reached a maximum speed of 279–280 km/h and a range of up to 3,500 km. The twin-hull configuration provided superior water handling stability, and the aircraft's three-rudder tail assembly gave it distinctive lateral control characteristics.
Savoia Marchetti S.55 — Record Breaker
Manuals Included in This Collection
- Savoia Marchetti S.55 Aircraft Erection and Maintenance Manual — Istruzioni per il Montaggio e la Regolazione (Italian Language), 1933 — approx. 69 pages
- Savoia Marchetti S.55 Aircraft Erection and Maintenance Manual — Istruzioni per il Montaggio e la Regolazione (Italian Language), undated edition — Società Idrovolanti Alta Italia, Sesto Calende
- Savoia Marchetti S.55 Illustrated Parts Catalog — Catalogo Nomenclatore per Idrovolante S.55 Serie 25 (Italian Language) — approx. 114 pages — Ministero dell'Aeronautica, Nomenclatore del Materiale Speciale d'Aeronautica, Vol. III, Cat. II, Fasc. 6°
- Savoia Marchetti S.55M Aircraft Erection and Maintenance Manual — Istruzioni per il Montaggio e la Regolazione (Italian Language) — Società Anonima Piaggio & C., Finale Ligure, Roma 1931 Anno IX + Technical Notes
- Savoia Marchetti S.55X° I.F. Asso 750 Aircraft Erection and Maintenance Manual — Istruzioni per il Montaggio e la Regolazione (Italian Language) — Serie 24+1 Scafi Allargatissimi per Crocera — C.A. 92 — Società Idrovolanti Alta Italia, Sesto Calende
- Savoia Marchetti S.55 Asso 500 RI Aircraft Erection and Maintenance Manual — Istruzioni per il Montaggio e la Regolazione (Italian Language) — Serie 8 Scafi Allargati — CA 50 — Società Idrovolanti Alta Italia, Sesto Calende
This collection covers the principal production variants of the S.55 family — from the early Asso 500 series through the S.55M military variant and the definitive S.55X Asso 750 transatlantic configuration — with documentation dating from the late 1920s through the mid-1930s.
Also Available: S.55 Blueprints & Engineering Drawings
We also offer the companion Savoia Marchetti S.55 Aircraft Blueprints & Engineering Drawings Collection — original factory drawings and structural schematics that pair directly with the manuals in this collection. Together they form the most comprehensive S.55 technical reference available in digital format.
Engineering Norms and Standards
The S.55 was designed and built to Italian Regia Aeronautica military specifications of the early 1920s, incorporating a mixed wood-and-metal structure with fabric covering on control surfaces. The wing center section featured significant structural thickness contributing directly to lift — a design norm later studied using modern FEM analysis techniques applied to composite materials. The tandem engine installation was inclined upward at 6–9 degrees to enhance takeoff performance and handling. Aerodynamic characteristics include a three-spar outer wing with 15-degree sweepback and aerodynamically balanced ailerons. Recent CFD studies by Team S55 at the Polytechnic of Turin (2020–2021), using ANSA meshing and Star CCM+ simulations, have validated the original wind tunnel data and pressure coefficient distributions across the airfoil sections.
Performance Reference Data
- Maximum Speed: 205 km/h (early variants) to 279–280 km/h (S.55X)
- Cruise Speed: 160–170 km/h (early) / 233 km/h (S.55X)
- Range: 1,200 km to 3,500 km (model and fuel load dependent)
- Maximum Takeoff Weight: 8,260 kg
Format and Delivery
Instant digital download. All documents are provided as high-resolution PDFs, optimized for screen reading and printing. Files are organized in a clearly labeled folder hierarchy by document type and variant. Compatible with all standard PDF readers on desktop, tablet, and mobile devices.
Disclaimer: These documents are provided for historical reference and research purposes only. They do not constitute airworthiness documentation and should not be used as the basis for any maintenance or operational decisions on airworthy aircraft. All trade names and designations remain the property of their respective owners. This digital compilation, structure, indexing and presentation are © Sicuro Publishing.