{"product_id":"boeing-247-r-1340-hamilton-standard-43d51-technical-documentation","title":"Boeing 247 — Pratt \u0026 Whitney R-1340 \u0026 Hamilton Standard 43D51 Propeller — Primary-Source Technical Documentation","description":"\u003ch2\u003eBoeing 247 — Primary-Source Technical Documentation Archive\u003c\/h2\u003e\n\n\u003cp\u003eThe Boeing 247, introduced in 1933, is widely celebrated as the world's first modern commercial airliner. It revolutionized aviation by combining an all-metal semimonocoque construction, a cantilever low-wing design, fully retractable landing gear, and pilot-controlled trim tabs into a single high-efficiency platform. This collection preserves the surviving primary-source technical publications covering the 247's two core systems: its Pratt \u0026amp; Whitney R-1340 Wasp radial engines and its Hamilton Standard 43D51-series variable-pitch propellers.\u003c\/p\u003e\n\n\u003ch3\u003eUnderstanding What Engineering Blueprints Are — and Are Not\u003c\/h3\u003e\n\n\u003cp\u003eThese are original factory-issued and military-authority-issued technical publications — not simplified guides, not hobby plans, and not RC or scale model references. They assume professional-level technical reading ability: tolerances, material specifications, assembly sequences, and maintenance references written for qualified mechanics and engineers.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eExplicit buyer disqualifier:\u003c\/strong\u003e If you are looking for simplified construction plans to build a replica or an RC model, this is not the right product for you.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eExplicit buyer qualifier:\u003c\/strong\u003e If you are a researcher, restorer, museum professional, or serious engineer who needs access to the deepest available layer of surviving primary-source factory documentation — this is it.\u003c\/p\u003e\n\n\u003chr\u003e\n\n\u003ch3\u003e✈️ Aerodynamic Design \u0026amp; Engineering Overview\u003c\/h3\u003e\n\n\u003cp\u003e\u003cstrong\u003eAirfoil:\u003c\/strong\u003e Engineered using the proprietary Boeing 106B airfoil template. The fully cantilevered wing eliminated all external bracing wires and struts, reducing parasitic drag to a historically low total Cd of 0.0214 (induced Cdi of 0.0014 at maximum cruise).\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eCowling evolution:\u003c\/strong\u003e The baseline 247 used Townend \"speed-ring\" cowlings; the 247D upgraded to fully streamlined NACA cowlings for optimized cooling with minimal parasitic drag.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eStressed-skin construction:\u003c\/strong\u003e Aluminum alloy stressed-skin engineering allowed the external fuselage skin to carry aerodynamic loads directly, minimizing interior structural weight — a defining innovation of the era.\u003c\/p\u003e\n\n\u003chr\u003e\n\n\u003ch3\u003e⚙️ Propulsion: Pratt \u0026amp; Whitney R-1340 Wasp\u003c\/h3\u003e\n\n\u003cp\u003eTwo Pratt \u0026amp; Whitney R-1340 Wasp — single-row, 9-cylinder, air-cooled radial engines. The 247D's definitive S1H1-G geared variant produced \u003cstrong\u003e550 hp per engine at 2,200 RPM at 8,000 feet\u003c\/strong\u003e. Total fuel capacity: 273 US gallons in wing-stub tanks; combined burn rate approximately 69 US gallons per hour.\u003c\/p\u003e\n\n\u003ch4\u003eR-1340 Documentation Included\u003c\/h4\u003e\n\u003cul\u003e\n\u003cli\u003eAir Depot Progressive Overhaul Manual — WWII-era, December 1943 (marked Restricted at time of issue)\u003c\/li\u003e\n\u003cli\u003eAN 02A-10DC-2 — Handbook Service Instructions, R-1340-AN-1 Aircraft Engines (April 1946, revised December 1948)\u003c\/li\u003e\n\u003cli\u003eUSAF TO 2R-R1340-3 \/ Navy AN 02A-10DC-3 — Handbook Overhaul Instructions, R-1340-AN-1 Aircraft Engines (April 1945, revised May 1957)\u003c\/li\u003e\n\u003cli\u003eNAVAIR 02A-10DC-4B \/ USAF TO 2R-R1340-4 — Technical Manual Illustrated Parts Breakdown, R-1340 series USAF \u0026amp; Navy models (August 1967)\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003chr\u003e\n\n\u003ch3\u003e🔩 Propeller: Hamilton Standard 43D51 Variable-Pitch Series\u003c\/h3\u003e\n\n\u003cp\u003eInitial 247 variants used fixed or ground-adjustable Hamilton Standard propellers — a configuration that severely limited single-engine climb performance. The 247D introduced two-bladed variable-pitch (controllable) propellers, allowing pilots to select blade pitch for optimized takeoff climb versus high-altitude cruise. This was the single modification that resolved the 247's early single-engine altitude limitation above 2,000 feet.\u003c\/p\u003e\n\n\u003ch4\u003eHamilton Standard 43D51 Documentation Included\u003c\/h4\u003e\n\u003cul\u003e\n\u003cli\u003eNAVAIR 03-20CBBC-1 — Technical Manual: Operation and Maintenance Instructions, Variable Pitch Aircraft Propeller, Models 43D51-303, -329, -341, -343, -355 (1 November 1963, changed 15 November 1970)\u003c\/li\u003e\n\u003cli\u003eNAVAIR 03-20CBBC-2 — Technical Manual: Overhaul Instructions, Variable Pitch Aircraft Propeller, Models 43D51-303, -341, -343, -355 (1 February 1964, changed 1 December 1970)\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003chr\u003e\n\n\u003ch3\u003e🕹️ Handling \u0026amp; Stability\u003c\/h3\u003e\n\n\u003cp\u003eThe 247 was the first twin-engine passenger transport structurally capable of maintaining altitude and climbing safely with one engine completely inoperative — a capability fully unlocked only with the introduction of variable-pitch propellers on the 247D. Pilot-controlled trim tabs across all tail surfaces allowed hands-off stability adjustment. A low landing speed of approximately 62 mph (100 km\/h) meant trailing-edge flaps were unnecessary. The aircraft also integrated a mechanical gyroscopic autopilot and active rubber de-icing boots on wing and tail leading edges.\u003c\/p\u003e\n\n\u003chr\u003e\n\n\u003ch3\u003e📊 Performance Data — Boeing 247D\u003c\/h3\u003e\n\n\u003ctable\u003e\n\u003cthead\u003e\u003ctr\u003e\n\u003cth\u003eParameter\u003c\/th\u003e\n\u003cth\u003eValue\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eMaximum Speed (Vne)\u003c\/td\u003e\n\u003ctd\u003e200 mph \/ 322 km\/h\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCruising Speed\u003c\/td\u003e\n\u003ctd\u003e189 mph \/ 304 km\/h\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eService Ceiling\u003c\/td\u003e\n\u003ctd\u003e25,400 ft \/ 7,740 m\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMax Rate of Climb\u003c\/td\u003e\n\u003ctd\u003e1,150 ft\/min \/ 351 m\/min\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eRange\u003c\/td\u003e\n\u003ctd\u003e~745 mi \/ 1,200 km\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMTOW\u003c\/td\u003e\n\u003ctd\u003e13,650 lbs \/ 6,192 kg\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eEmpty Weight\u003c\/td\u003e\n\u003ctd\u003e8,921 lbs \/ 4,046 kg\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWingspan\u003c\/td\u003e\n\u003ctd\u003e74 ft 1 in \/ 22.58 m\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWing Area\u003c\/td\u003e\n\u003ctd\u003e836 sq ft \/ 77.7 m²\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003chr\u003e\n\n\u003ch3\u003e📋 Historical Context\u003c\/h3\u003e\n\n\u003cp\u003eThough highly innovative, the 247 carried a structural compromise that defined its commercial limits: the main wing spar ran transversely through the passenger cabin floor, requiring the 10 passengers to step over it to move through the cabin. Because Boeing allocated its entire initial production to United Airlines, competing carriers turned to Douglas — which answered with the DC-2 and DC-3, aircraft that surpassed the 247 in cabin space, comfort, and speed. The 247 ultimately transitioned to military transport service as the C-73 during World War II.\u003c\/p\u003e\n\n\u003chr\u003e\n\n\u003cp\u003e⚠️ \u003cstrong\u003eRegulatory Notice:\u003c\/strong\u003e Under FAA 14 CFR § 43.13 and EASA Part-M, any mechanic performing maintenance on an active aircraft must use current, manufacturer-approved revision-controlled data. This archival document does not satisfy that requirement.\u003c\/p\u003e\n\n\u003cp\u003eThis is an archival, static-copy edition fixed at its original publication date. Intended for historical reference, flight simulation, museum restoration, and educational use only. Not approved for active airworthiness maintenance under FAA 14 CFR § 43.13, EASA Part-M, or equivalent international regulations. Operators of active aircraft must use current, revision-controlled publications from the Type Certificate holder or an authorized distributor.\u003c\/p\u003e\n\n\u003cp\u003eLiving Collections with Free Lifetime Updates – Please review our Legal Notice and Export Notice before purchasing.\u003c\/p\u003e","brand":"Online Aviation Library","offers":[{"title":"Default Title","offer_id":53936441721179,"sku":null,"price":89.0,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0955\/4788\/3867\/files\/boeing-247-colour-banner.png?v=1788183654","url":"https:\/\/onlineaviationlibrary.com\/products\/boeing-247-r-1340-hamilton-standard-43d51-technical-documentation","provider":"Online Aviation Library","version":"1.0","type":"link"}