Pratt & Whitney R-1340 Wasp Aircraft Engine Manuals Collection

This authoritative digital collection brings together the essential technical documentation for the legendary Pratt & Whitney R-1340 Wasp — the 9-cylinder single-row air-cooled radial engine that launched Pratt & Whitney as a company, defined the standard for American military aviation in the 1920s and 1930s, and powered the most iconic trainers of World War II. Sourced from original manufacturer and military publications, these manuals cover the full spectrum of maintenance, overhaul, parts identification, and operational procedures used by engineers and mechanics throughout the engine's distinguished service life.

Definitive Collection with Free Lifetime Updates

This is a living collection that we continuously expand and refine. As we acquire additional R-1340 Wasp 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

The Pratt & Whitney R-1340 Wasp was not an evolution of an earlier engine — it was Pratt & Whitney's very first design, conceived from a blank sheet to meet a demanding U.S. Navy requirement: a 400 hp air-cooled radial engine weighing less than 650 lbs. Frederick Rentschler and his team at the newly formed Pratt & Whitney Aircraft Company delivered something that exceeded every expectation. The Wasp first ran on Christmas Eve 1925, took to the air in May 1926, and passed its gruelling 50-hour Navy qualification test without a single failure — an unprecedented achievement for the era. It produced 410 horsepower at 650 lbs, a power-to-weight ratio that seemed impossible at the time and immediately rendered competing liquid-cooled inline engines obsolete for most applications.

The R-1340's impact on military aviation was swift and profound. Through the late 1920s and 1930s it powered the Boeing P-26 Peashooter — America's first all-metal monoplane fighter — the Boeing F2B-1 carrier fighter, and the Curtiss P-36 Hawk, establishing the Wasp as the standard powerplant for U.S. Army and Navy frontline aircraft of the interwar period. It also powered the CAC Wirraway, Australia's primary advanced trainer and light attack aircraft of the early war years. On the civilian side, the R-1340 found its way into the Lockheed Model 10 Electra, the Lockheed Model 5C Vega, the Ford Trimotor, the Noorduyn Norseman bush transport, and the legendary Gee Bee Super Sport Star racer — a testament to its versatility across the full spectrum of aviation.

During World War II, the Wasp became the heartbeat of Allied pilot training. The North American T-6 Texan (known as the Harvard in British Commonwealth service and the SNJ in U.S. Navy service) and the Boeing Stearman PT-17 Kaydet — both R-1340-powered — trained hundreds of thousands of Allied pilots who went on to fly P-51 Mustangs, P-47 Thunderbolts, and F4U Corsairs in combat. Every American fighter pilot of the war first learned to fly in a Wasp-powered aircraft. The engine's reliability and forgiving power delivery made it ideal for training, while its robust construction withstood the punishment of student pilots learning aerobatics and combat maneuvers day after day.

Pratt & Whitney produced 34,966 R-1340 engines between 1926 and 1960, with power output evolving from 400 hp in the original Wasp to over 600 hp in late supercharged and geared variants. Key variants included the R-1340-A through -D series, the S1D1, S3H1, S3H1-G (geared), and SC1, with differences centred on supercharger ratios, gear reduction arrangements, and power output. The engine's two-piece forged aluminium crankcase, one-piece master rod with silver-lead-indium bearing, and single-speed centrifugal supercharger were engineering firsts that became industry standards. Post-war, the Wasp found new roles in agricultural aviation, bush transport (Noorduyn Norseman), and early helicopter applications — most notably the Sikorsky S-55/H-19 and the Agusta-Bell AB.102 — demonstrating a versatility that extended its operational life decades beyond its original military mandate.

Today, the R-1340 Wasp remains very much alive. Hundreds of North American T-6/Harvard trainers, Boeing Stearmans, Noorduyn Norsemans, and de Havilland Otters continue to fly at airshows and in private collections worldwide, their Wasp engines providing the authentic sound and experience of vintage aviation. The Type Certificate is held by Pratt & Whitney, and active Service Bulletins and Airworthiness Directives govern ongoing maintenance — making this collection's original documentation an essential reference for any owner or A&P mechanic working on these aircraft today.

Manuals Included in This Collection

• Pratt & Whitney WASP S1H1 & S1H1-G — Specific Operating Instructions (Part No. 121511, PWA O.I. 71B) — January 27, 1947 / Revised February 1, 1960
• Pratt & Whitney WASP S3H1, S1H1, S1H2 and S3H1G — Maintenance Manual (Part No. 118611) — April 1962 / Revised May 1966
• Pratt & Whitney WASP S3H1, S1H1, S1H2 and S3H1G — Illustrated Parts Catalog (Part No. 86013) — Reissue April 1962 / Revised October 1970
• Pratt & Whitney R-1340 H1, H1G / R-1690 E, EG, E2G, E3G — Spare Parts Catalog — April 1, 1939 / Revised October 15, 1940
• Pratt & Whitney R-1340 -40, -48, -52, -57 — Handbook Service Instructions (AN 02A-10DD-2 / T.O. 2R-R1340-12) — 1 April 1951 / Revised 1 July 1958
• Pratt & Whitney R-1340 — Technical Manual Illustrated Parts Breakdown (NAVAIR 02A-10DC-4B / T.O. 2R-R1340-4) — 1 August 1967
• Pratt & Whitney R-1340 — Operators Handbook Wasp H-1 and Hornet E — January 1, 1937 / Revised January 1, 1939
• Pratt & Whitney R-1340 — Operators Handbook Wasp and Hornet / Wasp Junior (Book 1) — Revised January 1, 1936
• Pratt & Whitney R-1340 — Overhaul Changes Applicable to R-1340 Series Engines (T.O. 2R-R1340-5) — 1 June 1954 / Revised 1 April 1956
• Pratt & Whitney R-1340 AN-1 — Air Depot Progressive Overhaul Manual — December 10, 1943
• Pratt & Whitney R-1340 AN-1 — Handbook Service Instructions (AN 02A-10DC-2) — 19 April 1946 / Revised 15 December 1948
• Pratt & Whitney R-1340 AN-1 — Handbook Overhaul Instructions (T.O. 2R-R1340-3 / AN 02A-10DC-3) — 10 April 1945 / Revised 10 May 1957
• Pratt & Whitney — Overhaul Manual: Wasp Jr. (R-985) B4/B5 & Wasp (R-1340) S1H1, S3H1 and S3H1-G Engines (Part No. 123440) — March 1948
• T.O. 02-1-38 — Specified and Alternate Grade Fuel for Aircraft-Engine Combinations — 10 February 1945 / Revised 1 March 1945
• Pratt & Whitney Aircraft — Service School Handbook — April 1948

This collection spans documentation from 1936 through 1970, covering the full range of R-1340 variants from the earliest civilian Wasp operators handbooks through military AN-1 series technical orders and into the definitive 1960s S-series maintenance and parts publications — providing mechanics, restorers, and historians with authoritative references across the engine's entire production and service history.

Engineering Norms and Standards

The R-1340 was designed to meet U.S. Navy and U.S. Army Air Corps military specifications, with civilian variants certified under CAA/FAA Type Certificate authority held by Pratt & Whitney. Key engineering parameters: 9 cylinders, single-row radial, air-cooled; 1,344 cu in (22.02 L) displacement; 5.75 in × 5.75 in bore and stroke; 6:1 compression ratio; 91 octane minimum fuel; weight 650–930 lbs depending on variant and gearbox fitment. Pratt & Whitney engineering practices emphasised modular construction with individually replaceable cylinder assemblies, standardised master rod and articulated rod configurations, and a single-speed centrifugal supercharger. Military Technical Orders governed overhaul intervals, torque values, clearance limits, and approved repair procedures. These manuals reflect those exacting standards and provide the authoritative source data for any restoration or maintenance programme.

Specialized Documentation

The R-1340 benefits from an active airworthiness support structure. Active Service Bulletins and Airworthiness Directives (ADs) govern ongoing operation, and strict maintenance compliance is required for continued airworthiness. Supplemental Type Certificates (STCs) exist for modern ignition upgrades, fuel system modifications, and alternative oil systems. This collection's original documentation provides the essential baseline against which all modern modifications, STCs, and current ADs are referenced.

Where to Find Additional Documentation

• Official Support: Pratt & Whitney (current Type Certificate holder) — current Service Bulletins, ADs, and approved maintenance data
• Historical Archives: T-6 Harvard Texan type clubs, Warbird Information Exchange, EAA Warbirds of America, and the National Air and Space Museum technical library
• Specialty Vendors: Radial engine overhaul shops and Online Aviation Library for additional variant documentation

Format and Delivery

All manuals are delivered as high-resolution PDF files, optimised for both on-screen reference and print use. Files are organised by document type and variant for easy navigation. Instant download upon purchase — no waiting, no shipping. Compatible with all PDF readers on desktop, tablet, and mobile devices.

Disclaimer

These documents are provided for historical reference and research purposes. Always consult the current Type Certificate holder and approved maintenance data for any airworthiness decisions. No guarantee is made as to the completeness or currency of any document for active maintenance use. All trade names and trademarks are the property of their respective owners. Copyright © Sicuro Publishing.