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79-494: The Douglas DC-3 is a propeller -driven airliner manufactured by Douglas Aircraft Company , which had a lasting effect on the airline industry in the 1930s to 1940s and World War II . It was developed as a larger, improved 14-bed sleeper version of the Douglas DC-2 . It is a low-wing metal monoplane with conventional landing gear , powered by two radial piston engines of 1,000–1,200 hp (750–890 kW). Although

158-566: A Santa Fe Railway train for a second overnight rail trip to Clovis, New Mexico . There, they took a second Ford Trimotor flight to Los Angeles, with three stops along the way, eventually arriving at 5:52pm Pacific time at the Grand Central Airport in Glendale . The return journey departed from Los Angles at 8:45am and arrived at Now York at 9:50am in the morning of the third day. The one-way fare from New York to Los Angeles

237-545: A 48-hour coast to coast trip with the passengers taking flights during the day and trains by night. The first leg on the Pennsylvania Railroad departed from New York City at 6:05pm Eastern time and travelled overnight to Columbus, Ohio . There, passengers boarded a Ford Trimotor aircraft at what is now John Glenn Columbus International Airport , and flew to Waynoka, Oklahoma , an 11-hour flight that required four brief stops. At Waynoka, passengers boarded

316-464: A bent aluminium sheet for blades, thus creating an airfoil shape. They were heavily undercambered , and this plus the absence of lengthwise twist made them less efficient than the Wright propellers. Even so, this was perhaps the first use of aluminium in the construction of an airscrew. Originally, a rotating airfoil behind the aircraft, which pushes it, was called a propeller, while one which pulled from

395-473: A childhood fascination with the Chinese flying top, developed a model of feathers, similar to that of Launoy and Bienvenu, but powered by rubber bands. By the end of the century, he had progressed to using sheets of tin for rotor blades and springs for power. His writings on his experiments and models would become influential on future aviation pioneers. William Bland sent designs for his "Atmotic Airship" to

474-461: A craft that weighed 3.5 long tons (3.6 t), with a 110 ft (34 m) wingspan that was powered by two 360 hp (270 kW) steam engines driving two propellers. In 1894, his machine was tested with overhead rails to prevent it from rising. The test showed that it had enough lift to take off. One of Pénaud's toys, given as a gift by their father , inspired the Wright brothers to pursue

553-557: A decommissioned model is attached to the store. There is dine-in seating available in the plane. Related development Aircraft of comparable role, configuration, and era Related lists Propeller (aircraft) The propeller attaches to the power source's driveshaft either directly or through reduction gearing . Propellers can be made from wood, metal or composite materials . Propellers are most suitable for use at subsonic airspeeds generally below about 480 mph (770 km/h), although supersonic speeds were achieved in

632-416: A fixed-pitch prop once airborne. The spring-loaded "two-speed" VP prop is set to fine for takeoff, and then triggered to coarse once in cruise, the propeller remaining coarse for the remainder of the flight. After World War I , automatic propellers were developed to maintain an optimum angle of attack. This was done by balancing the centripetal twisting moment on the blades and a set of counterweights against

711-467: A large number of blades. A fan therefore produces a lot of thrust for a given diameter but the closeness of the blades means that each strongly affects the flow around the others. If the flow is supersonic, this interference can be beneficial if the flow can be compressed through a series of shock waves rather than one. By placing the fan within a shaped duct , specific flow patterns can be created depending on flight speed and engine performance. As air enters

790-528: A low- drag wing and as such are poor in operation when at other than their optimum angle of attack . Therefore, most propellers use a variable pitch mechanism to alter the blades' pitch angle as engine speed and aircraft velocity are changed. A further consideration is the number and the shape of the blades used. Increasing the aspect ratio of the blades reduces drag but the amount of thrust produced depends on blade area, so using high-aspect blades can result in an excessive propeller diameter. A further balance

869-415: A propeller efficiency of about 73.5% at cruise for a Cessna 172 . This is derived from his "Bootstrap approach" for analyzing the performance of light general aviation aircraft using fixed pitch or constant speed propellers. The efficiency of the propeller is influenced by the angle of attack (α). This is defined as α = Φ - θ, where θ is the helix angle (the angle between the resultant relative velocity and

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948-453: A propeller suffers when transonic flow first appears on the tips of the blades. As the relative air speed at any section of a propeller is a vector sum of the aircraft speed and the tangential speed due to rotation, the flow over the blade tip will reach transonic speed well before the aircraft does. When the airflow over the tip of the blade reaches its critical speed , drag and torque resistance increase rapidly and shock waves form creating

1027-454: A sharp increase in noise. Aircraft with conventional propellers, therefore, do not usually fly faster than Mach 0.6. There have been propeller aircraft which attained up to the Mach 0.8 range, but the low propeller efficiency at this speed makes such applications rare. The tip of a propeller blade travels faster than the hub. Therefore, it is necessary for the blade to be twisted so as to decrease

1106-583: A small coaxial modeled after the Chinese top but powered by a wound-up spring device and demonstrated it to the Russian Academy of Sciences . It was powered by a spring, and was suggested as a method to lift meteorological instruments. In 1783, Christian de Launoy , and his mechanic , Bienvenu, used a coaxial version of the Chinese top in a model consisting of contrarotating turkey flight feathers as rotor blades, and in 1784, demonstrated it to

1185-417: A spring and the aerodynamic forces on the blade. Automatic props had the advantage of being simple, lightweight, and requiring no external control, but a particular propeller's performance was difficult to match with that of the aircraft's power plant. The most common variable pitch propeller is the constant-speed propeller . This is controlled by a hydraulic constant speed unit (CSU). It automatically adjusts

1264-546: A thunderstorm; the three crew and five passengers on board were killed. The September crash was the first of three serious accidents for TAT over the next five months. Two of the Ford Tri-Motors that flew the transcontinental route with TAT, are preserved in flying condition: The Western New Mexico Aviation Heritage Museum in Grants, New Mexico, has a restored light and arrow which was used to direct pilots along

1343-735: A trip entailed short hops in slower and shorter-range aircraft during the day, coupled with train travel overnight . Several radial engines were offered for the DC-3. Early-production civilian aircraft used either the 9-cylinder Wright R-1820 Cyclone 9 or the 14-cylinder Pratt & Whitney R-1830 Twin Wasp , but the Twin Wasp was chosen for most military versions and was also used by most DC-3s converted from military service. Five DC-3S Super DC-3s with Pratt & Whitney R-2000 Twin Wasps were built in

1422-891: Is a conversion of the DC-3/C-47. Basler refurbishes C-47s and DC-3s at Oshkosh , Wisconsin , fitting them with Pratt & Whitney Canada PT6A-67R turboprop engines, lengthening the fuselage by 40 in (1,000 mm) with a fuselage plug ahead of the wing, and some local strengthening of the airframe. South Africa-based Braddick Specialised Air Services International (commonly referred to as BSAS International) has also performed Pratt & Whitney PT6 turboprop conversions, having performed modifications on over 50 DC-3/C-47s / 65ARTP / 67RTP / 67FTPs. American Airlines inaugurated passenger service on June 26, 1936, with simultaneous flights from Newark, New Jersey and Chicago , Illinois. Early U.S. airlines like American , United , TWA , Eastern , and Delta ordered over 400 DC-3s. These fleets paved

1501-613: Is estimated about 150 are still flying. "DC" stands for "Douglas Commercial". The DC-3 was the culmination of a development effort that began after an inquiry from Transcontinental and Western Airlines (TWA) to Donald Douglas . TWA's rival in transcontinental air service, United Airlines , was starting service with the Boeing 247 , and Boeing refused to sell any 247s to other airlines until United's order for 60 aircraft had been filled. TWA asked Douglas to design and build an aircraft that would allow TWA to compete with United. Douglas' design,

1580-455: Is hydraulic, with engine oil serving as the hydraulic fluid. However, electrically controlled propellers were developed during World War II and saw extensive use on military aircraft, and have recently seen a revival in use on home-built aircraft. Another design is the V-Prop , which is self-powering and self-governing. On most variable-pitch propellers, the blades can be rotated parallel to

1659-479: Is suitable for airliners, but the noise generated is tremendous (see the Antonov An-70 and Tupolev Tu-95 for examples of such a design). Forces acting on the blades of an aircraft propeller include the following. Some of these forces can be arranged to counteract each other, reducing the overall mechanical stresses imposed. The purpose of varying pitch angle is to maintain an optimal angle of attack for

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1738-409: Is that using a smaller number of blades reduces interference effects between the blades, but to have sufficient blade area to transmit the available power within a set diameter means a compromise is needed. Increasing the number of blades also decreases the amount of work each blade is required to perform, limiting the local Mach number – a significant performance limit on propellers. The performance of

1817-489: Is used to help slow the aircraft after landing and is particularly advantageous when landing on a wet runway as wheel braking suffers reduced effectiveness. In some cases reverse pitch allows the aircraft to taxi in reverse – this is particularly useful for getting floatplanes out of confined docks. Counter-rotating propellers are sometimes used on twin-engine and multi-engine aircraft with wing-mounted engines. These propellers turn in opposite directions from their counterpart on

1896-545: The French Academy of Sciences . A dirigible airship was described by Jean Baptiste Marie Meusnier presented in 1783. The drawings depict a 260-foot-long (79 m) streamlined envelope with internal ballonets that could be used for regulating lift. The airship was designed to be driven by three propellers. In 1784 Jean-Pierre Blanchard fitted a hand-powered propeller to a balloon, the first recorded means of propulsion carried aloft. Sir George Cayley , influenced by

1975-578: The McDonnell XF-88B experimental propeller-equipped aircraft. Supersonic tip-speeds are used in some aircraft like the Tupolev Tu-95 , which can reach 575 mph (925 km/h). The earliest references for vertical flight came from China. Since around 400 BC, Chinese children have played with bamboo flying toys . This bamboo-copter is spun by rolling a stick attached to a rotor between one's hands. The spinning creates lift, and

2054-403: The Tupolev Tu-95 propel it at a speed exceeding the maximum once considered possible for a propeller-driven aircraft using an exceptionally coarse pitch. Early pitch control settings were pilot operated, either with a small number of preset positions or continuously variable. The simplest mechanism is the ground-adjustable propeller , which may be adjusted on the ground, but is effectively

2133-698: The 1933 DC-1 , was promising, and led to the DC-2 in 1934. The DC-2 was a success, but with room for improvement. The DC-3 resulted from a marathon telephone call from American Airlines CEO C. R. Smith to Donald Douglas, when Smith persuaded a reluctant Douglas to design a sleeper aircraft based on the DC-2 to replace American's Curtiss Condor II biplanes. The DC-2's cabin was 66 inches (1.7 m) wide, too narrow for side-by-side berths. Douglas agreed to go ahead with development only after Smith informed him of American's intention to purchase 20 aircraft. The new aircraft

2212-520: The DC-2 in service from Amsterdam via Batavia (now Jakarta ) to Sydney , by far the world's longest scheduled route at the time. In total, KLM bought 23 DC-3s before the war broke out in Europe. In 1941, a China National Aviation Corporation (CNAC) DC-3 pressed into wartime transportation service was bombed on the ground at Suifu Airfield in China, destroying the outer right wing. The only spare available

2291-400: The DC-3/C-47 and related types, which would have made it impracticable to provide a comprehensive listing of all operators. A common saying among aviation enthusiasts and pilots is "the only replacement for a DC-3 is another DC-3". Its ability to use grass or dirt runways makes it popular in developing countries or remote areas, where runways may be unpaved. The oldest surviving DST is N133D,

2370-628: The DC-3s originally built for civil service had the Wright R-1820 Cyclone , later civilian DC-3s used the Pratt & Whitney R-1830 Twin Wasp engine. The DC-3 has a cruising speed of 207 mph (333 km/h), a capacity of 21 to 32 passengers or 6,000 lbs (2,700 kg) of cargo, and a range of 1,500 mi (2,400 km), and can operate from short runways. The DC-3 had many exceptional qualities compared to previous aircraft. It

2449-545: The DST was given the designation DC-3 . No prototype was built, and the first DC-3 built followed seven DSTs off the production line for delivery to American Airlines. The DC-3 and DST popularized air travel in the United States. Eastbound transcontinental flights could cross the U.S. in about 15 hours with three refueling stops, while westbound trips against the wind took 17 + 1 ⁄ 2 hours. A few years earlier, such

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2528-535: The Great Exhibition held in London in 1851, where a model was displayed. This was an elongated balloon with a steam engine driving twin propellers suspended underneath. Alphonse Pénaud developed coaxial rotor model helicopter toys in 1870, also powered by rubber bands. In 1872 Dupuy de Lome launched a large navigable balloon, which was driven by a large propeller turned by eight men. Hiram Maxim built

2607-757: The Santa Monica production line, delivered on 2 March 1937), which appears at airshows around the United States and is owned and operated by the Flagship Detroit Foundation. The base price of a new DC-3 in 1936 was around $ 60,000–$ 80,000, and by 1960 used aircraft were available for $ 75,000. In 2023, flying DC-3s can be bought from $ 400,000-$ 700,000. As of 2024, the Basler BT-67 with additions to handle cold weather and snow runways are used in Antarctica including regularly landing at

2686-626: The South Pole during the austral summer. Douglas C-47-DL serial number 41-7723 is on display at Pima Air & Space Museum near Tucson , Arizona . The aircraft was previously displayed at the United States Air Force Museum . Data from McDonnell Douglas Aircraft since 1920 General characteristics Performance An attraction for the city Taupō in New Zealand , is a McDonald's outlet, where

2765-620: The Soviet Union as the Lisunov Li-2 (4,937 aircraft). After the war, thousands of cheap ex-military DC-3s became available for civilian use. Cubana de Aviación became the first Latin American airline to offer a scheduled service to Miami when it started its first scheduled international service from Havana in 1945 with a DC-3. Cubana used DC-3s on some domestic routes well into the 1960s. Douglas developed an improved version,

2844-603: The Super DC-3, with more power, greater cargo capacity, and an improved wing, but with surplus aircraft available for cheap, they failed to sell well in the civilian aviation market. Only five were delivered, three of them to Capital Airlines . The U.S. Navy had 100 of its early R4Ds converted to Super DC-3 standard during the early 1950s as the Douglas R4D-8/C-117D . The last U.S. Navy C-117 was retired July 12, 1976. The last U.S. Marine Corps C-117, serial 50835,

2923-626: The US Navy with the designation YC-129 alongside 100 R4Ds that had been upgraded to the Super DC-3 specifications. From the early 1950s, some DC-3s were modified to use Rolls-Royce Dart engines, as in the Conroy Turbo Three . Other conversions featured Armstrong Siddeley Mamba or Pratt & Whitney PT6 A turbines . The Greenwich Aircraft Corp DC-3-TP is a conversion with an extended fuselage and with Pratt & Whitney Canada PT6A-65AR or PT6A-67R engines fitted. The Basler BT-67

3002-399: The air in the propeller slipstream. Contra-rotation also increases the ability of a propeller to absorb power from a given engine, without increasing propeller diameter. However the added cost, complexity, weight and noise of the system rarely make it worthwhile and it is only used on high-performance types where ultimate performance is more important than efficiency. A fan is a propeller with

3081-428: The aircraft maintain speed and altitude with the operative engines. Feathering also prevents windmilling , the turning of engine components by the propeller rotation forced by the slipstream; windmilling can damage the engine, start a fire, or cause structural damage to the aircraft. Most feathering systems for reciprocating engines sense a drop in oil pressure and move the blades toward the feather position, and require

3160-405: The airflow to stop rotation of the propeller and reduce drag when the engine fails or is deliberately shut down. This is called feathering , a term borrowed from rowing . On single-engined aircraft, whether a powered glider or turbine-powered aircraft, the effect is to increase the gliding distance. On a multi-engine aircraft, feathering the propeller on an inoperative engine reduces drag, and helps

3239-471: The airliner market, around ninety percent of airline flights on the planet were by a DC-3 or some variant. Following the war, the airliner market was flooded with surplus transport aircraft, and the DC-3 was no longer competitive because it was smaller and slower than aircraft built during the war. It was made obsolete on main routes by more advanced types such as the Douglas DC-4 and Convair 240 , but

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3318-410: The angle of attack of the blade gradually and therefore produce uniform lift from the hub to the tip. The greatest angle of incidence, or the highest pitch, is at the hub while the smallest angle of incidence or smallest pitch is at the tip. A propeller blade designed with the same angle of incidence throughout its entire length would be inefficient because as airspeed increases in flight, the portion near

3397-407: The blade pitch in order to maintain a constant engine speed for any given power control setting. Constant-speed propellers allow the pilot to set a rotational speed according to the need for maximum engine power or maximum efficiency, and a propeller governor acts as a closed-loop controller to vary propeller pitch angle as required to maintain the selected engine speed. In most aircraft this system

3476-440: The blade rotation direction) and Φ is the blade pitch angle. Very small pitch and helix angles give a good performance against resistance but provide little thrust, while larger angles have the opposite effect. The best helix angle is when the blade is acting as a wing producing much more lift than drag. However, 'lift-and-drag' is only one way to express the aerodynamic force on the blades. To explain aircraft and engine performance

3555-403: The blade tips approach the speed of sound. The maximum relative velocity is kept as low as possible by careful control of pitch to allow the blades to have large helix angles. A large number of blades are used to reduce work per blade and so circulation strength. Contra-rotating propellers are used. The propellers designed are more efficient than turbo-fans and their cruising speed (Mach 0.7–0.85)

3634-635: The company lost $ 2.7 million ($ 49.2 million in 2023). In November 1929 TAT bought Maddux Air Lines . The company was tendering to the United States Postal Service for the contract for the New York to Los Angeles air mail route. However, before granting the contract Walter Folger Brown , the US postmaster general forced TAT to merge with Western Air Express to form Transcontinental & Western Air (T&WA). In October 1930,

3713-680: The design proved adaptable and was still useful on less commercially demanding routes. Civilian DC-3 production ended in 1943 at 607 aircraft. Military versions, including the C-47 Skytrain (the Dakota in British RAF service), and Soviet- and Japanese-built versions, brought total production to over 16,000. Many continued to be used in a variety of niche roles; 2,000 DC-3s and military derivatives were estimated to be still flying in 2013; by 2017 more than 300 were still flying. As of 2023 it

3792-467: The dream of flight. The twisted airfoil (aerofoil) shape of an aircraft propeller was pioneered by the Wright brothers. While some earlier engineers had attempted to model air propellers on marine propellers , the Wright Brothers realized that a propeller is essentially the same as a wing , and were able to use data from their earlier wind tunnel experiments on wings, introducing a twist along

3871-470: The duct needs to be shaped in a different manner than one for higher speed flight. More air is taken in and the fan therefore operates at an efficiency equivalent to a larger un-ducted propeller. Noise is also reduced by the ducting and should a blade become detached the duct would help contain the damage. However the duct adds weight, cost, complexity and (to a certain degree) drag. Transcontinental Air Transport Transcontinental Air Transport (T-A-T)

3950-575: The duct, its speed is reduced while its pressure and temperature increase. If the aircraft is at a high subsonic speed this creates two advantages: the air enters the fan at a lower Mach speed; and the higher temperature increases the local speed of sound. While there is a loss in efficiency as the fan is drawing on a smaller area of the free stream and so using less air, this is balanced by the ducted fan retaining efficiency at higher speeds where conventional propeller efficiency would be poor. A ducted fan or propeller also has certain benefits at lower speeds but

4029-431: The feathering process or the feathering process may be automatic. Accidental feathering is dangerous and can result in an aerodynamic stall ; as seen for example with Yeti Airlines Flight 691 which crashed during approach due to accidental feathering. The propellers on some aircraft can operate with a negative blade pitch angle, and thus reverse the thrust from the propeller. This is known as Beta Pitch. Reverse thrust

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4108-463: The front was a tractor . Later the term 'pusher' became adopted for the rear-mounted device in contrast to the tractor configuration and both became referred to as 'propellers' or 'airscrews'. The understanding of low speed propeller aerodynamics was fairly complete by the 1920s, but later requirements to handle more power in a smaller diameter have made the problem more complex. Propeller research for National Advisory Committee for Aeronautics (NACA)

4187-574: The fuselage – clockwise on the left engine and counterclockwise on the right – however, there are exceptions (especially during World War II ) such as the P-38 Lightning which turned "outwards" (counterclockwise on the left engine and clockwise on the right) away from the fuselage from the WW II years, and the Airbus A400 whose inboard and outboard engines turn in opposite directions even on

4266-414: The hub would have a negative AOA while the blade tip would be stalled. There have been efforts to develop propellers and propfans for aircraft at high subsonic speeds. The 'fix' is similar to that of transonic wing design. Thin blade sections are used and the blades are swept back in a scimitar shape ( scimitar propeller ) in a manner similar to wing sweepback, so as to delay the onset of shockwaves as

4345-484: The late 1940s, three of which entered airline service. Total production including all military variants was 16,079. More than 400 remained in commercial service in 1998. Production was: Production of DSTs ended in mid-1941 and civilian DC-3 production ended in early 1943, although dozens of the DSTs and DC-3s ordered by airlines that were produced between 1941 and 1943 were pressed into the US military service while still on

4424-400: The length of the blades. This was necessary to maintain a more uniform angle of attack of the blade along its length. Their original propeller blades had an efficiency of about 82%, compared to 90% for a modern (2010) small general aviation propeller, the 3-blade McCauley used on a Beechcraft Bonanza aircraft. Roper quotes 90% for a propeller for a human-powered aircraft. Mahogany was

4503-530: The new airline began an all-air, coast to coast passenger service that took 36 hours, with an overnight stop at Kansas City Western became an independent company once again in 1934. However, Transcontinental opted to retain the T&;WA name, and eventually evolved into Trans World Airlines or TWA. On September 3, 1929, NC9649 , named City of San Francisco , crashed into the forested slope of Mount Taylor near Grants, New Mexico . The crash took place during

4582-432: The other wing to balance out the torque and p-factor effects. They are sometimes referred to as "handed" propellers since there are left hand and right hand versions of each prop. Generally, the propellers on both engines of most conventional twin-engined aircraft spin clockwise (as viewed from the rear of the aircraft). To eliminate the critical engine problem, counter-rotating propellers usually turn "inwards" towards

4661-417: The pilot to pull the propeller control back to disengage the high-pitch stop pins before the engine reaches idle RPM . Turboprop control systems usually use a negative torque sensor in the reduction gearbox, which moves the blades toward feather when the engine is no longer providing power to the propeller. Depending on design, the pilot may have to push a button to override the high-pitch stops and complete

4740-400: The production line. Military versions were produced until the end of the war in 1945. A larger, more powerful Super DC-3 was launched in 1949 to positive reviews. The civilian market was flooded with second-hand C-47s, many of which were converted to passenger and cargo versions. Only five Super DC-3s were built, and three of them were delivered for commercial use. The prototype Super DC-3 served

4819-561: The propeller blades, giving maximum efficiency throughout the flight regime. This reduces fuel usage. Only by maximising propeller efficiency at high speeds can the highest possible speed be achieved. Effective angle of attack decreases as airspeed increases, so a coarser pitch is required at high airspeeds. The requirement for pitch variation is shown by the propeller performance during the Schneider Trophy competition in 1931. The Fairey Aviation Company fixed-pitch propeller used

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4898-411: The same force is expressed slightly differently in terms of thrust and torque since the required output of the propeller is thrust. Thrust and torque are the basis of the definition for the efficiency of the propeller as shown below. The advance ratio of a propeller is similar to the angle of attack of a wing. A propeller's efficiency is determined by Propellers are similar in aerofoil section to

4977-410: The same wing. A contra-rotating propeller or contra-prop places two counter-rotating propellers on concentric drive shafts so that one sits immediately 'downstream' of the other propeller. This provides the benefits of counter-rotating propellers for a single powerplant. The forward propeller provides the majority of the thrust, while the rear propeller also recovers energy lost in the swirling motion of

5056-408: The sixth Douglas Sleeper Transport built, manufactured in 1936. This aircraft was delivered to American Airlines on 12 July 1936 as NC16005. In 2011 it was at Shell Creek Airport, Punta Gorda, Florida . It has been repaired and has been flying again, with a recent flight on 25 April 2021. The oldest DC-3 still flying is the original American Airlines Flagship Detroit (c/n 1920, the 43rd aircraft off

5135-530: The toy flies when released. The 4th-century AD Daoist book Baopuzi by Ge Hong (抱朴子 "Master who Embraces Simplicity") reportedly describes some of the ideas inherent to rotary wing aircraft. Designs similar to the Chinese helicopter toy appeared in Renaissance paintings and other works. It was not until the early 1480s, when Leonardo da Vinci created a design for a machine that could be described as an "aerial screw" , that any recorded advancement

5214-444: The type's first flight in 1935, although the number is dwindling due to expensive maintenance and a lack of spare parts. There are small operators with DC-3s in revenue service and as cargo aircraft . Applications of the DC-3 have included passenger service, aerial spraying, freight transport, military transport, missionary flying, skydiver shuttling and sightseeing. There have been a very large number of civil and military operators of

5293-422: The versatility, rugged reliability, and economy of the DC-3. While newer airliners soon replaced it on longer high-capacity routes, it remained a significant part of air transport systems well into the 1970s as a regional airliner before being replaced by early regional jets . Perhaps unique among prewar aircraft, the DC-3 continues to fly in active commercial and military service as of 2021, eighty-six years after

5372-523: The war effort and more than 10,000 U.S. military versions of the DC-3 were built, under the designations C-47, C-53, R4D, and Dakota . Peak production was reached in 1944, with 4,853 being delivered. The armed forces of many countries used the DC-3 and its military variants for the transport of troops, cargo, and wounded. Licensed copies of the DC-3 were built in Japan as the Showa L2D (487 aircraft); and in

5451-408: The way for the modern American air travel industry, which eventually replaced trains as the favored means of long-distance travel across the United States. A nonprofit group, Flagship Detroit Foundation, continues to operate the only original American Airlines Flagship DC-3 with air show and airport visits throughout the U.S. In 1936, KLM Royal Dutch Airlines received its first DC-3, which replaced

5530-445: The wood preferred for propellers through World War I , but wartime shortages encouraged use of walnut , oak , cherry and ash . Alberto Santos Dumont was another early pioneer, having designed propellers before the Wright Brothers for his airships . He applied the knowledge he gained from experiences with airships to make a propeller with a steel shaft and aluminium blades for his 14 bis biplane in 1906. Some of his designs used

5609-568: Was $ 352 ($ 6,246 in 2023). The Ford Trimotor service was one of the first to offer meals en route, provided by the Fred Harvey Company . ; Fred Harvey also provided meals on the ground at several stops. The service was also one of the first to be geared toward passengers–most airlines at the time focused on transporting air mail. Cynics were to deride the TAT abbreviation as "Take A Train". And in its first eighteen months of operation,

5688-404: Was an airline founded in 1928 by Clement Melville Keys that merged in 1930 with Western Air Express to form what became TWA . Keys enlisted the help of Charles Lindbergh to design a transcontinental network to get government airmail contracts. Lindbergh established numerous airports across the country in this effort. On July 7, 1929, transcontinental trips began. It initially offered

5767-616: Was directed by William F. Durand from 1916. Parameters measured included propeller efficiency, thrust developed, and power absorbed. While a propeller may be tested in a wind tunnel , its performance in free-flight might differ. At the Langley Memorial Aeronautical Laboratory , E. P. Leslie used Vought VE-7s with Wright E-4 engines for data on free-flight, while Durand used reduced size, with similar shape, for wind tunnel data. Their results were published in 1926 as NACA report #220. Lowry quotes

5846-482: Was engineered by a team led by chief engineer Arthur E. Raymond over the next two years, and the prototype DST (Douglas Sleeper Transport) first flew on December 17, 1935 (the 32nd anniversary of the Wright Brothers ' flight at Kitty Hawk) with Douglas chief test pilot Carl Cover at the controls. Its cabin was 92 in (2,300 mm) wide, and a version with 21 seats instead of the 14–16 sleeping berths of

5925-483: Was fast, had a good range, was more reliable, and carried passengers in greater comfort. Before the World War II, it pioneered many air travel routes. It was able to cross the continental United States from New York to Los Angeles in 18 hours, with only three stops. It is one of the first airliners that could profitably carry only passengers without relying on mail subsidies. In 1939, at the peak of its dominance in

6004-506: Was made towards vertical flight. His notes suggested that he built small flying models, but there were no indications for any provision to stop the rotor from making the craft rotate. As scientific knowledge increased and became more accepted, man continued to pursue the idea of vertical flight. Many of these later models and machines would more closely resemble the ancient bamboo flying top with spinning wings, rather than Leonardo's screw. In July 1754, Russian Mikhail Lomonosov had developed

6083-447: Was partially stalled on take-off and up to 160 mph (260 km/h) on its way up to a top speed of 407.5 mph (655.8 km/h). The very wide speed range was achieved because some of the usual requirements for aircraft performance did not apply. There was no compromise on top-speed efficiency, the take-off distance was not restricted to available runway length and there was no climb requirement. The variable pitch blades used on

6162-582: Was retired from active service during June 1982. Several remained in service with small airlines in North and South America in 2006. The United States Forest Service used the DC-3 for smoke jumping and general transportation until the last example was retired in December 2015. A number of aircraft companies attempted to design a "DC-3 replacement" over the next three decades (including the very successful Fokker F27 Friendship ), but no single type could match

6241-454: Was that of a smaller Douglas DC-2 in CNAC's workshops. The DC-2's right wing was removed, flown to Suifu under the belly of another CNAC DC-3, and bolted up to the damaged aircraft. After a single test flight, in which it was discovered that it pulled to the right due to the difference in wing sizes, the so-called DC-2½ was flown to safety. During World War II, many civilian DC-3s were drafted for

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