Breguet Aviation
Louis-Charles Breguet was a French airplane designer and builder, born in Paris, France on January 2, 1880. The helicopter was probably invented by Louis Breguet in France in 1909 (credit for early development of the helicopter also goes to Igor Sikorsky and Juan de la Cierva). Scions of the famous clock- and watch-making family, with his brother, Jacques and under the guidance of Professor Charles Richet, Louis-Charles Breguet began work on a gyroplane (the forerunner of the helicopter) with flexible wings in 1905. It achieved the first ascension of a vertical-flight aircraft with a pilot in 1907.
The name of Breguet had previously attained a European renown. The science of mechanics applied to watchmaking, reveals a world of wonders; and hosts of ingenious artisans have distinguished themselves in the different branches of nautical, astronomical, and domestic horology. It would be impossible to mention the names alone of those who excelled in these various departments.
Louis Abraham [or Abraham Louis] Breguet was born at Neufchatel, in Switzerland, in 1747, of one of the numerous French families driven into exile by the revocation of the Edict of Nantes. His family were in reduced circumstances, and his father having died when he was still a child, his mother married a clockmaker, who endeavoured to teach the boy his trade. At school he had appeared hopelessly stupid, and his master pronounced him deficient in intellect. At the age of fifteen was apprenticed to a watchmaker at Versailles, in 1762. In the evenings he learned mathematics at the College Mazarin. A dim period followed, but in or about 1769 the young man is found established in business, among his customers being the King and Queen and Court. In 1775 A.L. Breguet set up his own business on Quai de l'Horloge, Ile de la cité in Paris. Before the revolution broke out in France, Breguet had already founded the establishment which afterwards produced so many masterpieces of mechanism and clockmaking, and his reputation was rapidly increasing.
Although quite indifferent to politics, he fell under the suspicion of the dominant party, and owed his safety only to the interposition of some friends, at whose solicitation he was permitted to leave France. Early in the Revolution, Breguet, who was a bit of a Sans Culotte, was instrumental in helping Marat to escape from an awkward situation, and Marat rewarded him by getting him a "safe pass" across the Channel in 1798. On his return to France, he found his establishment had been destroyed, but he opened a new one, and eventually it became more prosperous and successful than the former. Breguet became watch-maker to Napoleon and to the (other Buonapartes. A Pedometer Watch was made for him by Breguet. The great Corsican' s restless stride automatically kept this novel timepiece rewound. In England his fame was bright. George III went to Breguet for the time of day and so did the Prince Regent. The Duke of Wellington gave three thousand guineas for a Breguet and always wore it.
In 1807, Breguet took his son Louis Antoine into partnership and the watches were then often signed "Breguet et Fils." Louis Abraham Breguet made numerous improvements in watches and in nautical and astronomical instruments. The Breguet-Saxton metallic thermometer was first invented about 1817 by the instrument maker Louis Abraham Breguet. The first of this type was composed of platinum, silver, and gold with the silver placed in the center. Differential expansion of the metals provided the temperature measurement.
Louis Abraham Breguet died in 1823. The renown of Breguet's name was maintained by the skill of his nephew, who carried on his uncle's studies with great success, and retained the gold medal in the family. In 1853, when Louis Antoine Breguet retired, his son Louis Clement Francois Breguet succeeded. The last of the Breguets was Louis Antoine, who died in 1882, and with him the greatest days of the firm passed. This last Breguet was a mechanic of genius who worked for Graham Bell on the first telephones.
The number of references to Breguet watches in French and foreign literature is an indication of the remarkable reputation enjoyed by both the firm and its founder. Breguet is now so deeply rooted in European culture that the name is virtually a sine qua non of any depiction of the aristocracy, the bourgeoisie or, quite simply, a life of luxury and elegance.
In 1908, Louis-Charles Breguet and Charles Richet formed the Société des Ateliers d'Aviation and turned to fixed-wing planes. They produced their first biplane, the Breguet I, in 1909. It attracted a lot of attention at Reims with its original features, including its wide use of metal components. The plane featured wing-warping for longitudinal and lateral control. This first airplane built in 1909 set a speed record in 1911 for its 10-kilometer (6.2-mile) flight. Also that year, he founded the Société des Ateliers d'Aviation Louis Breguet.
Their next model, the Breguet III, appeared in 1912. It used sheet aluminum on the front part of the fuselage. That, and the whistling sound that it made in flight, gave it the nickname the "Tin Whistle." Breguet's later planes all were derived from the basic design of this tractor biplane. In 1912, Breguet constructed his first hydroplane.
The Breguet Bre. 14, first flown in 1917, was considered France's single most important and successful aircraft of the war. Almost 5,500 were built in the last two years of the war. The plane also made the first European airmail flights, served on the first passenger lines, and made some outstanding long-distance flights. In 1919, the Bre.14 flew 994 miles (1,600 kilometers) across the Mediterranean and back and 1,180 miles (1,900 kilometers) from Paris to Kenitra, Morocco. It remained in production until 1926.
He is especially known for his development of a reconnaissance airplane used by the French in World War I and through the 1920s. One of the pioneers in the construction of metal aircraft, the Breguet-14 day bomber, perhaps the most famous French warplane of all time, was made almost entirely of aluminum. As well as the French, sixteen squadrons of the American Expeditionary Force also used it.
In 1919, Breguet founded the Compagnie des Messageries Aeriennes, which evolved into Air France. Over the years, his aircraft set several records. A Breguet plane made the first nonstop crossing of the South Atlantic in 1927. Another made a 4,500-mile (7,242-kilometer) flight across the Atlantic Ocean in 1933, the longest nonstop Atlantic flight up to that time.
The biggest problem with the various early helicopter designs produced by Louis and Jacques Bréguet, Igor Sikorsky, Juan de la Cierva, and others was that although they could lift off the ground, they could not be controlled in flight. Inventors did not understand the aeronautical forces facing the helicopter and did not know how to design mechanical devices to address these forces.
By the early 1930s, Louis Bréguet, one of the pioneers of helicopter development, began to think about helicopters again, establishing the Syndicate for Gyroplane Studies and hiring a young engineer named Rene Dorand. Bréguet took a far more cautious approach than he had more than a decade before. He oversaw the building of a helicopter that attempted to solve the problems of stability and control. He cautiously named this aircraft the Gyroplane-Laboratoire, clearly identifying it as an experimental aircraft.
To make the most of a limited budget, Dorand built the craft as much as possible from available bits and pieces. He used a Bréguet 19 airplane fuselage for the craft's body and a surplus aircraft engine to power it. The craft consisted of a thin metallic frame with a tail and three wheels-one on either side mounted on outriggers and a smaller one at the front of the aircraft. The engine was located forward, and the pilot sat behind it in an open cage. Two twin-bladed rotors, each nearly 54 feet (16.5 meters) long, were stacked coaxially on top of each other, rotating in opposite directions and thereby canceling out their torque. The rotor blades were attached to the shaft with a hinge mechanism (they were "articulated"), and the pitch of the rotor could be increased or decreased on each revolution (cyclic pitch control), thereby controlling lift. If the propellers were angled so they pushed the air down more, lift would increase, and the craft would rise.
Bréguet had confidence in his machine despite warnings from his mechanics that the controls were not yet perfected. In November 1933, he scheduled a demonstration flight for his investors. A former French Army pilot, Maurice Claisse, reluctantly agreed to make the test. He climbed into the craft and started the engine as three men stood by on the ground to hold the machine. The rotors turned and the craft immediately tilted to the right. As bystanders-including the ground-handlers-ran for cover, the rotor blades hit the ground and shattered. Fortunately, no one was hurt, but the aircraft was badly damaged, postponing any further tests.
Throughout 1934 and 1935, Bréguet extensively modified his craft and performed ground tests. His most important addition was a new system for controlling the direction of flight. By tilting the axle on which the rotors turned, pitching the rotor disk, the helicopter could be made to move forward, sideways, or even backward. He added a system for controlling the yaw of the helicopter (turning the helicopter to the left or right) by allowing the two rotors to each have a different pitch (differential collective pitch).
On June 26, 1935, test pilot Maurice Claisse hopped in the craft again. This time he was able to lift it off the ground without crashing. He then made several flights at speeds of 18 to 30 miles per hour (29 to 48 kilometers per hour). The French Air Ministry was so impressed it gave Bréguet a contract that covered the cost of flight trials and provided a million-franc-bonus if all performance goals were achieved. On December 22, 1935, it established a Federation Aeronautique Internationale speed record of 67 miles per hour (108 kilometers per hour). It was the first to demonstrate speed as well as good control characteristics. The next year, it set an altitude record of 517 feet (158 meters).
Bréguet received another Air Ministry contract for further development but made little progress over the next several years. One big concern about helicopters was what would happen if the engine failed in flight. An airplane could glide to the ground, but a helicopter needed to descend while "autorotating," essentially using the rotor as a parachute. Bréguet's aircraft was badly damaged during an autorotation test in 1939. With war imminent, Bréguet put his craft in storage and turned his attention to the full-scale production of bombers. His helicopter was ultimately destroyed in 1943 during the Allied bombing of the Villacoublay Airfield.
Breguet remained an important manufacturer of aircraft during World War II and afterwards developed commercial transports. Louis-Charles Breguet died on May 4, 1955 in Paris, France.
The US NASA Ames Center had a joint program with the French Air Ministry and the Breguet Aircraft Co. to investigate the handling qualities, stability and control and operational characteristics of the Breguet 941 (deflected slipstream) transport. Two major tests were carried out in France on the Breguet 941, a four-engine, deflected-propeller slipstream transport, to determine the aircraft's performance and flying qualities, and to explore its operation in low-visibility instrument flight conditions.
The Government, worried about the development of the Jaguar program, asked Marcel Dassault to buy back Breguet Aviation. On June 27, 1967, the Société des Avions Marcel Dassault company acquired a 66% share in Breguet Aviation's capital held by Sylvain Floirat and the Penhoet company. On the same day, Breguet Aviation's Board of Directors appointed Benno Claude Vallières as its chairman. A merger deal involving Breguet Aviation taking over the net assets of the Société des Avions Marcel Dassault company was signed on July 21, 1971.
From the mid 1960s onwards, the French State encouraged a general concentration process in order to promote companies able to rival their international competitors. In the airframes field, two companies were still be business at the time: Société nationale industrielle Aérospatiale (SNIAS) and Avions Marcel Dassault-Breguet Aviation (AMD-BA). As a result of the government directives of the minister of the Armed forces, Pierre Messmer, they became specialized in 1965: Aérospatiale in civil aviation, helicopters, missiles and satellites, and Dassault-Breguet in combat aircraft and business aviation.
The range of an aircraft is proportional to its lift-to-drag ratio, as determined by Breguet's equation. The Breguet Range Equation is used to calculate the range of an aircraft given a specific flight plan or profile. A typical flight profile includes taxi and takeoff, steep initial climb, climb, cruise, descent, approach and landing. The changing weight of the aircraft as it burns fuel is also taken into consideration. Furthermore, reserves are also calculated as part of a contingency plan for when an approach is missed, which would require additional maneuvers and flight time. To find the range is much more complex than simply dividing the total fuel by the average hourly fuel consumption and then multiplying by the velocity. That's why we need the Breguet Range equation to predict how far an airplane will fly accounting for flight performance and the change in weight of the airplane as it burns or uses its fuel.
Breguet 940 Breguet 941
The Breguet 941, prototype STOL troop transport was developed by the French firm, "Societe Anonyme des Ateliers d'Aviation, Louis Breguet" as a follow-on to the Ereguet 940, an experimental flight research STOL vehicle which first flew in May, 1958. The Breguet 941 prototype, which first flew in June 1961, incorporates design concepts which were developed through the Breguet 940 program. After completion of contractor tests on the airplwne in 1962, the prototype was turned over to the French Air Force for testing equivalent to the U. S. Air Force Category II tests. These tests were completed in the Spring of 1963. At that time, a ten hour flight evaluation of the airplane was conducted by National Aeronautics Space Administration (NASA) personnel.
The airplane utilizes 'the deflected slipstream principle to obtain STOL performance. Basic design concept was to use the deflected slipstream principle coupled with a control system and a power train which would give satisfactory flying qualities and flight safety in the speed regimes possible through use of this principle. The Breguet 941 prototype STOL troop/cargo transport airplane, of all metal high wing configuration, is powered by four turbo-prop power plants and uses the deflected slipstream principle to attain STOL performance. All propellers are interconnccted by shafting so as to eliminate engine-out asymmetric thrust.
The cargo compartment of the airplane contains seats for 56 troops or provisions for 24 stretchers. Cargo or troops are loaded through an aft clamshell door and a ramp which can be adjusted to truck bed level or lowered to the ground for wheeled vehicle entry. Clamshell doors are hydraulically actuated. Cockpit of the airplane contains stations for a crew of three. Pilot and co-pilot seats are located side by side. A flight engineers seat is located behind the co-pilots seat with access to various engine and environmental controls located on the right side of the cockpit.
Test results indicated that the Breguet 941 prototype had good potential for use as a medium STOL troop/cargo transport. STOL performance appears to be comparable to medium STOL airplanes in service use and under development by the U.S. Army. Conventional performance (rate of climb, cruise speed and range) appears to exceed that of medium STOL transports now in service use and should be comparable to that projected for the medium SIOL transport now being developed (based on contractor data). Airplane configuration and contractor information indicate that service ceiling of the prototype is limited to 18,000 ft.
STOL take-off and landing characteristics are generally satisfactory. Techniques used to obtain STOL performance require no unusual degree of skill or pilot effort. It appears that further refinement of contractor recomnded techniques is possible and will produce an improvement in STOL performance over that obtained in this evaluation. Engine-out characteristics are particularly compatible with the STOL capability of the airplane due to the use of the propeller cross-shaft system. Controlled flight at STOL speeds is possible followiny asymetric power failure and the complete STOL take-off and landing sequence can be completed under asymmetric thrust conditions. Propeller cross-shafting should be considered for use in other STOL multi-engine airplanes of interest to the US Army. In the STOL configuration, longitudinal flying qualities are satisfactory, but both lateral and directional characteristics are unsatisfactory due to weak static lateral-directional stability and low damping of dynamic lateral-directional oscillations. Flying qualities during the transition from the STOL take-off configuration to the clean climb configuration are unsatisfactory due to the method and fast rate of operation of the flaps and due to excessive pitch trim changes during the transition sequence.
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