The Naval Aircraft Factory PN was a series of open cockpit American flying boats of the 1920s and 1930s. A development of the Felixstowe F5L flying boat of the World War I , variants of the PN were built for the United States Navy by Douglas , Keystone and Martin .
81-450: The PN flying boats were twin-engine biplanes with their engines mounted in nacelles between the fabric-covered wings. Other than on the PN-11 which had a different hull form, the hull had large chines running back to the first step similar to those on the F.5L. It had a standard crew of five, but was capable of carrying a relief crew for long patrols. Early machines had wood hulls and wings, with
162-411: A monoplane is its ability to combine greater stiffness with lower weight. Stiffness requires structural depth and where early monoplanes had to have this provided with external bracing, the biplane naturally has a deep structure and is therefore easier to make both light and strong. Rigging wires on non-cantilevered monoplanes are at a much sharper angle, thus providing less tension to ensure stiffness of
243-426: A biplane has the wings positioned directly one above the other. Moving the upper wing forward relative to the lower one is called positive stagger or, more often, simply stagger. It can increase lift and reduce drag by reducing the aerodynamic interference effects between the two wings by a small degree, but more often was used to improve access to the cockpit. Many biplanes have staggered wings. Common examples include
324-641: A division. McDonnell Douglas merged with Boeing in 1997. The company was founded as the Douglas Company by Donald Wills Douglas Sr. on July 22, 1921, in Santa Monica, California , following dissolution of the Davis-Douglas Company. An early claim to fame was the first circumnavigation of the world by air in Douglas airplanes in 1924. In 1923, the U.S. Army Air Service was interested in carrying out
405-608: A documented jet-kill, as one Lockheed F-94 Starfire was lost while slowing down to 161 km/h (100 mph) – below its stall speed – during an intercept in order to engage the low flying Po-2. Later biplane trainers included the de Havilland Tiger Moth in the Royal Air Force (RAF), Royal Canadian Air Force (RCAF) and others and the Stampe SV.4 , which saw service postwar in the French and Belgian Air Forces. The Stearman PT-13
486-509: A faster and more comfortable successor to the Dragon. As the available engine power and speed increased, the drag penalty of external bracing increasingly limited aircraft performance. To fly faster, it would be necessary to reduce external bracing to create an aerodynamically clean design; however, early cantilever designs were either too weak or too heavy. The 1917 Junkers J.I sesquiplane utilized corrugated aluminum for all flying surfaces, with
567-525: A heart as a reference to the Clan Douglas . After the success of the DWC, the company adopted a logo that showed three airplanes circling a globe. The logo eventually evolved into an aircraft, a missile, and a globe. This logo was later adopted by McDonnell Douglas in 1967, and became the basis of Boeing 's current logo after their merger in 1997. Douglas Aircraft designed and built a wide variety of aircraft for
648-432: A low wing loading , combining both large wing area with light weight. Obtaining a large enough wing area without the wings being long, and thus dangerously flexible was more readily accomplished with a biplane. The smaller biplane wing allows greater maneuverability . Following World War I, this helped extend the era of the biplane and, despite the performance disadvantages, most fighter aircraft were biplanes as late as
729-507: A minimum of struts; however, it was relatively easy to damage the thin metal skin and required careful handling by ground crews. The 1918 Zeppelin-Lindau D.I fighter was an all-metal stressed-skin monocoque fully cantilevered biplane, but its arrival had come too late to see combat use in the conflict. By the 1930s, biplanes had reached their performance limits, and monoplanes become increasingly predominant, particularly in continental Europe where monoplanes had been increasingly common from
810-615: A mission to circumnavigate the Earth for the first time by aircraft , a program called "World Flight". Donald Douglas proposed a modified Douglas DT to meet the Army's needs. The two-place, open cockpit DT biplane torpedo bomber had previously been produced for the U.S. Navy . The DTs were taken from the assembly lines at the company's manufacturing plants in Rock Island, Illinois , and Dayton, Ohio , to be modified. The modified aircraft known as
891-735: A number of aircraft including the C-47 Skytrain, the DB-7 (known as the A-20, Havoc or Boston), the SBD Dauntless dive bomber , and the A-26 Invader . Douglas Aircraft suffered cutbacks at the end of the war, with an end to government aircraft orders and a surplus of aircraft. It was necessary to cut heavily into its workforce, letting go of nearly 100,000 workers. The United States Army Air Forces established 'Project RAND' (Research ANd Development) with
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#1733084580221972-569: A redesigned broad-chord tail to fix a vibration problem. Four PN-10 s were built, and while similar to the PN-9, each was given a different engine as the Packard 1A-2500 engines were disappointing. One was fitted with Packard 1A-1500 and another with a Packard 3A-1500 , both V-12 water-cooled engines and one each was fitted with the Wright R-1820 and Pratt & Whitney R-1690 radial engines. The wings of
1053-418: A series of long-distance flights. During the afternoon of 31 August 1925, an attempt was made to fly a pair of PN-9 planes non-stop from San Francisco to Hawaii , a distance of nearly 2,400 miles (3,864 km) — a trip anticipated to take 26 hours to complete. The first plane to start was forced to land 300 miles (480 km) outside of San Francisco due to a failure of oil pressure, with the crew rescued by
1134-473: A somewhat unusual sesquiplane arrangement, possessing a more substantial lower wing with two spars that eliminated the flutter problems encountered by single-spar sesquiplanes. The stacking of wing planes was suggested by Sir George Cayley in 1843. Hiram Maxim adopted the idea for his steam-powered test rig, which lifted off but was held down by safety rails, in 1894. Otto Lilienthal designed and flew two different biplane hang gliders in 1895, though he
1215-529: A wholly owned subsidiary of McDonnell Douglas, with Douglas' son, Donald Wills Douglas Jr. , as president. Later, former McDonnell president David S. Lewis became chairman of Douglas Aircraft. His successful turnaround of the division allowed him to become president of McDonnell Douglas in 1969. Meanwhile, Douglas' space and missiles division became part of a new subsidiary called McDonnell Douglas Astronautics Company. McDonnell Douglas later merged with its rival Boeing in 1997. Boeing merged Douglas Aircraft into
1296-486: Is a fixed-wing aircraft with two main wings stacked one above the other. The first powered, controlled aeroplane to fly, the Wright Flyer , used a biplane wing arrangement, as did many aircraft in the early years of aviation . While a biplane wing structure has a structural advantage over a monoplane , it produces more drag than a monoplane wing. Improved structural techniques, better materials and higher speeds made
1377-411: Is a two bay biplane , the extra bay being necessary as overlong bays are prone to flexing and can fail. The SPAD S.XIII fighter, while appearing to be a two bay biplane, has only one bay, but has the midpoints of the rigging braced with additional struts; however, these are not structurally contiguous from top to bottom wing. The Sopwith 1½ Strutter has a W shape cabane, however as it does not connect
1458-547: Is better known for his monoplanes. By 1896 a group of young men in the United States, led by Octave Chanute , were flying hang gliders including biplanes and concluded that the externally braced biplane offered better prospects for powered flight than the monoplane. In 1903, the Wright Flyer biplane became the first successful powered aeroplane. Throughout the pioneer years, both biplanes and monoplanes were common, but by
1539-609: Is much more common. The space enclosed by a set of interplane struts is called a bay (much as the architectural form is used), hence a biplane or triplane with one set of such struts connecting the wings on each side of the aircraft is a single-bay biplane . This provided sufficient strength for smaller aircraft such as the First World War -era Fokker D.VII fighter and the Second World War de Havilland Tiger Moth basic trainer. The larger two-seat Curtiss JN-4 Jenny
1620-636: The B-17 Flying Fortress . After the war, Douglas built another Boeing design under license, the B-47 Stratojet turbojet -powered bomber, using a government-owned factory in Marietta, Georgia . World War II was a major boost for Douglas. Douglas ranked fifth among United States corporations in the value of wartime production contracts. The company produced almost 30,000 aircraft from 1942 to 1945, and its workforce swelled to 160,000. The company produced
1701-803: The Boeing Commercial Airplanes division, and retired the Douglas Aircraft name after 76 years. The last Long Beach -built commercial aircraft, the Boeing 717 (third generation version of the Douglas DC-9), ceased production in May 2006. By 2011, the Boeing C-17 Globemaster III was the last aircraft being assembled at the Long Beach facility; the final C-17 was assembled in late 2015. However,
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#17330845802211782-524: The Bristol M.1 , that caused even those with relatively high performance attributes to be overlooked in favour of 'orthodox' biplanes, and there was an allegedly widespread belief held at that time that monoplane aircraft were inherently unsafe during combat. Between the years of 1914 and 1925, a clear majority of new aircraft introduced were biplanes; however, during the latter years of the First World War,
1863-684: The Grumman Ag Cat are available in upgraded versions with turboprop engines. The two most produced biplane designs were the 1913 British Avro 504 of which 11,303 were built, and the 1928 Soviet Polikarpov Po-2 of which over 20,000 were built, with the Po-2 being the direct replacement for the Soviet copy of the Avro 504. Both were widely used as trainers. The Antonov An-2 was very successful too, with more than 18,000 built. Although most ultralights are monoplanes,
1944-595: The Lite Flyer Biplane, the Sherwood Ranger , and the Murphy Renegade . The feathered dinosaur Microraptor gui glided, and perhaps even flew, on four wings, which may have been configured in a staggered sesquiplane arrangement. This was made possible by the presence of flight feathers on both forelimbs and hindlimbs, with the feathers on the forelimbs opening to a greater span. It has been suggested that
2025-539: The Nieuport-Delage NiD 42 / 52 / 62 series, Fokker C.Vd & e, and Potez 25 , all serving across a large number of air forces. In the general aviation sector, aircraft such as the Waco Custom Cabin series proved to be relatively popular. The Saro Windhover was a sesquiplane with the upper wing smaller than the lower, which was a much rarer configuration than the reverse. The Pfalz D.III also featured
2106-585: The Northrop Corporation . The company retained its military market and expanded into amphibian airplanes in the late 1920s, also moving its facilities to Clover Field at Santa Monica, California . The Santa Monica complex was so large, the mail girls used roller skates to deliver the intracompany mail. By the end of World War II, Douglas had facilities at Santa Monica, El Segundo , Long Beach , and Torrance, California , Tulsa and Midwest City , Oklahoma, and Chicago, Illinois . On November 30, 1928,
2187-834: The PM-1 and PM-2 . These each had their own differences from the PN-12, as the Keystone PK-1 and Martin PM-2 the twin fins and rudders of the PN-11, while the PM-1 and PM-2 also had an enclosed cockpit, and the PK-1 had a modified hull form with a sharper bow. These also formed the basis for the Hall PH flying boats, with a different hull fitted with an enclosed cockpit, and some of these remained in service until World War II . The early prototypes of PN sea planes were used in
2268-659: The Saturn IB and Saturn V rockets. In 1967, the company was struggling to expand production to meet demand for DC-8 and DC-9 airliners and the A-4 Skyhawk military attack aircraft. The company was also struggling with quality and cash flow problems and DC-10 development costs, as well as shortages due to the Vietnam War . Under the circumstances, Douglas was very receptive to an offer from McDonnell Aircraft Corporation . On April 28, 1967, after almost four years of merger talks,
2349-648: The XPN-11 , which was later redesignated as the XP4N-1 . Two aircraft were fitted with Wright R-1820 radial engines and while ordered as an XP4N-1 were designated as the XP4N-2 when they entered service. The two metal wing radial-engine powered PN-10s were redesignated as PN-12 s, which combined the revised wings of the PN-7 but reverted to the metal hull of the PN-8 with the enlarged chines and
2430-490: The de Havilland Tiger Moth , Bücker Bü 131 Jungmann and Travel Air 2000 . Alternatively, the lower wing can instead be moved ahead of the upper wing, giving negative stagger, and similar benefits. This is usually done in a given design for structural reasons, or to improve visibility. Examples of negative stagger include the Sopwith Dolphin , Breguet 14 and Beechcraft Staggerwing . However, positive (forward) stagger
2511-624: The "DC" (Douglas Commercial) series of commercial aircraft, including what is often regarded as the most significant transport aircraft ever made: the Douglas DC-3 , which was also produced as a military transport known as the C-47 Skytrain or "Dakota" in British service. Many Douglas aircraft have long service lives. During World War II , Douglas joined the BVD ( Boeing - Vega -Douglas) consortium to produce
Naval Aircraft Factory PN - Misplaced Pages Continue
2592-739: The British. The F.5L was a license-built version of the British Felixstowe F.5 using the American Liberty engine . The series of Felixstowe flying boats, developed by the Seaplane Experimental Station , had started with improving the hull of the Curtiss America . PN-5 was the new designation assigned to F.5Ls built by the Naval Aircraft Factory after 1922, although identical aircraft built before then retained
2673-503: The CR.42 was able to achieve success in the defensive night fighter role against RAF bombers that were striking industrial targets throughout northern Italy. The British Fleet Air Arm operated the Fairey Swordfish torpedo bomber from its aircraft carriers, and used the type in the anti-submarine warfare role until the end of the conflict, largely due to their ability to operate from
2754-518: The Caribou , performed the first non-stop flight between the Canadian mainland and Britain in 30 hours 55 minutes, although the intended target for this long distance flight had originally been Baghdad , Iraq . Despite its relative success, British production of the Dragon was quickly ended when in favour of the more powerful and elegant de Havilland Dragon Rapide , which had been specifically designed to be
2835-658: The Douglas World Cruiser (DWC), also was the first major project for Jack Northrop who designed the fuel system for the series. After the prototype was delivered in November 1923, upon the successful completion of tests on 19 November, the Army commissioned Douglas to build four production series aircraft. Due to the demanding expedition ahead, spare parts, including 15 extra Liberty L-12 engines, 14 extra sets of pontoons, and enough replacement airframe parts for two more aircraft were chosen. These were sent to airports along
2916-528: The F.5L designation. Under the new designation system, P indicated that the role was Patrol, and N denoted aircraft built by the US Navy's Naval Aircraft Factory. Numbers 1-4 were skipped. The PN-6 was had an enlarged curved fin with an unbalanced rudder. The first two examples had been ordered as the final two F.5Ls, and had been designated as F.6Ls, with the new PN-6 designation coming into effect in 1922. Some F.5L/PN-5s were later upgraded to PN-6 standard. Neither
2997-503: The First World War, the British Royal Aircraft Factory developed airfoil section wire named RAFwire in an effort to both increase the strength and reduce the drag. Four types of wires are used in the biplane wing structure. Drag wires inside the wings prevent the wings from being folded back against the fuselage, running inside a wing bay from the forward inboard corner to the rear outboard corner. Anti-drag wires prevent
3078-565: The French Nieuport 17 and German Albatros D.III , offered lower drag than a conventional biplane while being stronger than a monoplane. During the Interwar period , numerous biplane airliners were introduced. The British de Havilland Dragon was a particularly successful aircraft, using straightforward design to could carry six passengers on busy routes, such as London-Paris services. During early August 1934, one such aircraft, named Trail of
3159-644: The Germans had been experimenting with a new generation of monoplanes, such as the Fokker D.VIII , that might have ended the biplane's advantages earlier had the conflict not ended when it had. The French were also introducing the Morane-Saulnier AI , a strut-braced parasol monoplane , although the type was quickly relegated to the advanced trainer role following the resolution of structural issues. Sesquiplane types, which were biplanes with abbreviated lower wings such as
3240-763: The North American leg of the flight). After the success of this flight, the Army Air Service ordered six similar aircraft as observation aircraft. The success of the DWC established the Douglas Aircraft Company among the major aircraft companies of the world and led it to adopt the motto "First Around the World – First the World Around". Douglas initially used a logo that combined two letter Ds with two wings extended outwards, and two Ds placed back to back to form
3321-669: The PN-12 entered service with the US Navy from 30 April 1928, when VP-7D received its first Douglas PD-1, remaining in service until July 1938, when the last Keystone PK-1 was retired. Three Martin PM-1s were also supplied to the Brazilian Navy in 1930, and used in bombing raids during the 1932 revolution . Data from United States Navy Aircraft since 1911 General characteristics Performance Armament Related development Aircraft of comparable role, configuration, and era Related lists Biplane A biplane
Naval Aircraft Factory PN - Misplaced Pages Continue
3402-502: The PN-5 or the PN-6 designation was used outside of official paperwork, and these aircraft were simply referred to as F.5Ls. The PN-7 was a 1925 development with an improved thicker section, shorter-span wings with a more modern airfoil section, and were powered by two experimental 525 hp (391 kW) Wright T-2 V-12 engines . Two were built. The PN-8 was developed due to problems with
3483-416: The PN-9's flight path and was forced to land at sea when both engines stopped functioning. With power lost, the plane was unable to send or receive radio signals. Although this was at the time a new distance record for seaplanes , the plane remained hundreds of miles short of the nearest landfall and the situation of the crew, with limited quantities of food and water, appeared dire. Since seas were moderate,
3564-482: The U.S. Navy — the straight-winged F3D Skyknight in 1948 and then the more "jet age" style F4D Skyray in 1951. Douglas also made commercial jets, producing the Douglas DC-8 in 1958 to compete with the new Boeing 707 . Douglas was a pioneer in related fields, such as ejection seats , air-to-air missiles , surface-to-air missiles , and air-to-surface missiles , launch rockets, bombs, and bomb racks. The company
3645-542: The U.S. military, including the Navy, Army Air Forces, Marine Corps, Air Force, and Coast Guard. The company initially built torpedo bombers for the U.S. Navy, but it developed a number of different versions of these aircraft, including reconnaissance planes and airmail aircraft. Within five years, the company was building about 100 aircraft annually. Among the early employees at Douglas were Ed Heinemann , "Dutch" Kindelberger , Carl Cover , and Jack Northrop , who later founded
3726-483: The biplane configuration obsolete for most purposes by the late 1930s. Biplanes offer several advantages over conventional cantilever monoplane designs: they permit lighter wing structures, low wing loading and smaller span for a given wing area. However, interference between the airflow over each wing increases drag substantially, and biplanes generally need extensive bracing, which causes additional drag. Biplanes are distinguished from tandem wing arrangements, where
3807-461: The company was reorganized as the Douglas Aircraft Company. In 1934, Douglas produced a commercial twin-engined transport plane , the Douglas DC-2 , followed by the famous DC-3 in 1936. The wide range of aircraft produced by Douglas included airliners , light and medium bombers , fighter aircraft , transports, reconnaissance aircraft, and experimental aircraft. The company is most famous for
3888-598: The competition aerobatics role and format for such a biplane well-defined by the mid-1930s by the Udet U 12 Flamingo and Waco Taperwing . The Pitts Special dominated aerobatics for many years after World War II and is still in production. The vast majority of biplane designs have been fitted with reciprocating engines . Exceptions include the Antonov An-3 and WSK-Mielec M-15 Belphegor , fitted with turboprop and turbofan engines respectively. Some older biplane designs, such as
3969-410: The decision was made to attempt to sail the plane to Hawaii. The crew then rigged crude sails made from fabric torn from the aircraft's wings and sailed the aircraft a further 450 miles (720 km), finally being spotted on the ninth day about 15 miles (24 km) off the southeast coast of the Hawaiian island of Kauai . In the aftermath of the headline-grabbing rescue, Commander Rogers was promoted to
4050-410: The destroyer USS William Jones and the aircraft towed back to port. The second PN-9 to depart, captained by U.S. Navy Commander John Rodgers, flew 1,841 miles (2,963 km) before running out of fuel when anticipated tailwinds that would have slowed gasoline consumption did not materialize. The plane was unable to make contact with the naval airplane tender USS Aroostook , a ship stationed along
4131-484: The end of World War I . At the start of World War II , several air forces still had biplane combat aircraft in front line service but they were no longer competitive, and most were used in niche roles, such as training or shipboard operation, until shortly after the end of the war. The British Gloster Gladiator biplane, the Italian Fiat CR.42 Falco and Soviet I-153 sesquiplane fighters were all still operational after 1939. According to aviation author Gianni Cattaneo,
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#17330845802214212-497: The first two Packard powered aircraft had a wood structure, while the second pair with the radial engines had wings with a metal structure, both with a fabric covering. The four PN-11 s had a new metal hull with a round turtle deck and lacking the previously characteristic enlarged chines and had a new empennage with twin fins and rudders. One aircraft was fitted with two Wright R-1750 radial engines, while one aircraft were fitted with two Pratt & Whitney R-1690 radial engines as
4293-412: The hind limbs could not have opened out sideways but in flight would have hung below and slightly behind the fore limbs. Douglas Aircraft Company The Douglas Aircraft Company was an American aerospace and defense company based in Southern California . Founded in 1921 by Donald Wills Douglas Sr. , it merged with McDonnell Aircraft in 1967 to form McDonnell Douglas , where it operated as
4374-464: The less the interference, but the spacing struts must be longer, and the gap must be extremely large to reduce it appreciably. As engine power and speeds rose late in World War I , thick cantilever wings with inherently lower drag and higher wing loading became practical, which in turn made monoplanes more attractive as it helped solve the structural problems associated with monoplanes, but offered little improvement for biplanes. The default design for
4455-424: The low speeds and simple construction involved have inspired a small number of biplane ultralights, such as Larry Mauro's Easy Riser (1975–). Mauro also made a version powered with solar cells driving an electric motor called the Solar Riser . Mauro's Easy Riser was used by "Father Goose", Bill Lishman . Other biplane ultralights include the Belgian-designed Aviasud Mistral , the German FK12 Comet (1997–),
4536-412: The main wings can support ailerons , while flaps are more usually positioned on the lower wing. Bracing is nearly always added between the upper and lower wings, in the form of interplane struts positioned symmetrically on either side of the fuselage and bracing wires to keep the structure from flexing, where the wings are not themselves cantilever structures. The primary advantage of the biplane over
4617-411: The mid-1930s. Specialist sports aerobatic biplanes are still made in small numbers. Biplanes suffer aerodynamic interference between the two planes when the high pressure air under the top wing and the low pressure air above the lower wing cancel each other out. This means that a biplane does not in practice obtain twice the lift of the similarly-sized monoplane. The farther apart the wings are spaced
4698-453: The most famed copies was the Siemens-Schuckert D.I . The Albatros D.III and D.V , which had also copied the general layout from Nieuport, similarly provided the backbone of the German forces during the First World War. The Albatros sesquiplanes were widely acclaimed by their aircrews for their maneuverability and high rate of climb. During interwar period , the sesquiplane configuration continued to be popular, with numerous types such as
4779-422: The night ground attack role throughout the Second World War. In the case of the Po-2, production of the aircraft continued even after the end of the conflict, not ending until around 1952. A significant number of Po-2s were fielded by the Korean People's Air Force during the Korean War , inflicting serious damage during night raids on United Nations bases. The Po-2 is also the only biplane to be credited with
4860-476: The objective of looking into long-range planning of future weapons. In March 1946, Douglas Aircraft Company was granted the contract to research on intercontinental warfare. Project RAND later become the RAND Corporation . Douglas continued to develop new aircraft, including the successful four-engined Douglas DC-6 (1946) and its last propeller-driven commercial aircraft, the Douglas DC-7 (1953). The company had moved into jet propulsion, producing its first for
4941-438: The outbreak of the First World War biplanes had gained favour after several monoplane structural failures resulted in the RFC's "Monoplane Ban" when all monoplanes in military service were grounded, while the French also withdrew most monoplanes from combat roles and relegated them to training. Figures such as aviation author Bruce observed that there was an apparent prejudice held even against newly-designed monoplanes, such as
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#17330845802215022-406: The outer wing. On a biplane, since the angles are closer to the ideal of being in direct line with the forces being opposed, the overall structure can then be made stiffer. Because of the reduced stiffness, wire braced monoplanes often had multiple sets of flying and landing wires where a biplane could easily be built with one bay, with one set of landing and flying wires. The extra drag from the wires
5103-423: The position of Assistant Chief of the Navy's Bureau of Aeronautics. PN-9 No. 1, the same plane sailed to Hawaii, did not fare as well, later ditching in the Caribbean Sea during an attempted long-distance flight to South America and subsequently sunk as a navigation hazard. The two PN-12s were also used to set various records, including range and speed over circuit records. The various production derivatives of
5184-457: The relatively compact decks of escort carriers . Its low stall speed and inherently tough design made it ideal for operations even in the often severe mid-Atlantic weather conditions. By the end of the conflict, the Swordfish held the distinction of having caused the destruction of a greater tonnage of Axis shipping than any other Allied aircraft. Both the German Heinkel He 50 and the Soviet Polikarpov Po-2 were used with relative success in
5265-421: The route. The last of these aircraft was delivered to the U.S. Army on March 11, 1924. The four aircraft left Seattle , Washington, on April 6, 1924, flying west, and two of these returned there on 28 September to great acclaim, while one plane had been lost under fog conditions, and another was forced down over the Atlantic and sank (the DWC prototype was then rechristened, and joined the other two in completing
5346-499: The same overall strength and is therefore lighter. A given area of wing also tends to be shorter, reducing bending moments on the spars, which then allow them to be more lightly built as well. The biplane does however need extra struts to maintain the gap between the wings, which add both weight and drag. The low power supplied by the engines available in the first years of aviation limited aeroplanes to fairly low speeds. This required an even lower stalling speed, which in turn required
5427-502: The same portion of the atmosphere and thus interfere with each other's behaviour. In a biplane configuration with no stagger from the upper wing to the lower wing, the lift coefficient is reduced by 10 to 15 percent compared to that of a monoplane using the same airfoil and aspect ratio . The lower wing is usually attached to the fuselage , while the upper wing is raised above the fuselage with an arrangement of cabane struts , although other arrangements have been used. Either or both of
5508-442: The series of Nieuport military aircraft—from the Nieuport 10 through to the Nieuport 27 which formed the backbone of the Allied air forces between 1915 and 1917. The performance of the Nieuport sesquiplanes was so impressive that the Idflieg (the German Inspectorate of flying troops) requested their aircraft manufacturers to produce copies, an effort which was aided by several captured aircraft and detailed drawings; one of
5589-403: The two companies merged as McDonnell Douglas Corporation . The two companies seemed to be a good match for each other. McDonnell was a major defense contractor, but had almost no civilian business. Douglas' commercial contracts would allow McDonnell to withstand any downturns in procurement. Conversely, McDonnell had enough revenue to help solve Douglas' financial problems; soon after the merger
5670-400: The upper and lower wings together. The sesquiplane is a type of biplane where one wing (usually the lower) is significantly smaller than the other. The word, from Latin, means "one-and-a-half wings". The arrangement can reduce drag and weight while retaining the biplane's structural advantages. The lower wing may have a significantly shorter span, or a reduced chord . Examples include
5751-419: The wings are placed forward and aft, instead of above and below. The term is also occasionally used in biology , to describe the wings of some flying animals . In a biplane aircraft, two wings are placed one above the other. Each provides part of the lift, although they are not able to produce twice as much lift as a single wing of similar size and shape because the upper and the lower are working on nearly
5832-618: The wings covered in fabric, while various versions replaced these with metal components. A wide variety of V-12 and radial engines were fitted, due to problems with several of the engines chosen, with later versions generally using radial engines. At the end of World War I the United States Navy was operating the Curtiss H.16 and the Felixstowe F5L Long-range patrol flying boats , which had been developed in collaboration with
5913-434: The wings from folding up, and run from the underside of the outer wing to the lower wing root. Conversely, landing wires prevent the wings from sagging, and resist the forces when an aircraft is landing, and run from the upper wing centre section to outboard on the lower wings. Additional drag and anti-drag wires may be used to brace the cabane struts which connect the fuselage to the wings, and interplane struts, which connect
5994-421: The wings from moving forward when the aircraft stops and run the opposite direction to the drag wires. Both of these are usually hidden within the wings, and if the structure is sufficiently stiff otherwise, may be omitted in some designs. Indeed many early aircraft relied on the fabric covering of the wing to provide this rigidity, until higher speeds and forces made this inadequate. Externally, lift wires prevent
6075-597: The wings to each other, it does not add to the number of bays. Large transport and bombing biplanes often needed still more bays to provide sufficient strength. These are often referred to as multi-bay biplanes . A small number of biplanes, such as the Zeppelin-Lindau D.I have no interplane struts and are referred to as being strutless . Because most biplanes do not have cantilever structures, they require rigging wires to maintain their rigidity. Early aircraft used simple wire (either braided or plain), however during
6156-460: The wooden hull, which quickly absorbed hundreds of pounds of water and was maintenance intensive, so two aircraft with a metal hull of the same shape as the F.5Ls, and fitted with the new wing, were built. Due to reliability problems with the Wright T-2, they were powered by two 475 hp (354 kW) V-12 Packard 1A-2500 engines. The two PN-9 s were converted from PN-8s, after being fitted with
6237-457: Was announced, McDonnell bought 1.5 million shares of Douglas stock to help Douglas meet "immediate financial requirements". The merged company was based at McDonnell's facility in St. Louis, Missouri . It adopted a modified version of Douglas' logo. Donald Wills Douglas Sr. became honorary chairman of the merged company, a post he would hold until his death in 1981. Douglas Aircraft Company continued as
6318-575: Was fitted with the more reliable radial engines. The fin was further enlarged, with a straight leading edge. It would see extensive production to re-equip the Navy's patrol squadrons. As the production capacity of the Naval Aircraft Factory was limited, production was contracted out to several aircraft companies, with versions being built by Douglas as the PD-1 , by Keystone as the PK-1 and by Martin as
6399-423: Was not enough to offset the aerodynamic disadvantages from having two airfoils interfering with each other however. Strut braced monoplanes were tried but none of them were successful, not least due to the drag from the number of struts used. The structural forces acting on the spars of a biplane wing tend to be lower as they are divided between four spars rather than two, so the wing can use less material to obtain
6480-553: Was ready to enter the new missile business during the 1950s. Douglas moved from producing air-to-air rockets and missiles to entire missile systems under the 1956 Nike missile program and became the main contractor for the Skybolt air-launched ballistic missile program and the Thor ballistic missile program. Douglas also earned contracts from NASA, most notably for designing the S-IVB stage of
6561-691: Was widely used by the United States Army Air Force (USAAF) while the US Navy operated the Naval Aircraft Factory N3N . In later civilian use in the US, the Stearman became particularly associated with stunt flying such as wing-walking , and with crop dusting, where its compactness worked well at low levels, where it had to dodge obstacles. Modern biplane designs still exist in specialist roles such as aerobatics and agricultural aircraft with
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