High Quality Content by WIKIPEDIA articles! Two or more vortices that are approximately parallel and circulating in the same direction will merge to form a single vortex. The circulation of the merged vortex will equal the sum of the circulations of the constituent vortices. For example, a sheet of small vortices flows from the trailing edge of the wing or propeller of an airplane when the wing is developing lift or the propeller is developing thrust. In less than one wing chord downstream of the trailing edge of the wing these small vortices merge to form a single vortex. If viewed from the tail of the airplane, looking forward in the direction of flight, there is one wingtip vortex trailing from the left-hand wing and circulating clockwise, and another wingtip vortex trailing from the right-hand wing and circulating anti-clockwise.
High Quality Content by WIKIPEDIA articles! The Van's RV-12 is two-seat, single-engine, low-wing homebuilt airplane eligible for the US LSA category sold in kit form by Van's Aircraft. The RV-12 had its first flight on November 9, 2006. Deliveries of partial kits commenced in April 2008 and by May 2010, 34 aircraft had flown. The prototype incorporates several new features for an RV-series aircraft including: removable wings, full-span flaperons and an all-moving stabilator. It is intended that the RV-12 will be powered by a Rotax 912S engine of 100 hp and equipped with a Sensenich composite ground-adjustable propeller.
High Quality Content by WIKIPEDIA articles! The Air & Space 18A is a gyroplane manufactured in the central United States between 1965 and 2000. The Air & Space 18A is one of the last three gyroplanes issued a Standard Airworthiness Certificate (September 1961) by the United States Federal Aviation Administration (FAA). Raymond E. Umbaugh, a manufacturer of agricultural fertilizer, founded Umbaugh Aircraft Corporation in Ocala, Florida, in 1957 to develop a gyroplane based on experience he acquired while modifying single-seat Bensen Gyrocopters. Gilbert Devore commenced the design of Umbaugh's tandem two-seat jump-takeoff gyroplane in 1958, basing the rotor system on that of the Sznycer Omega BS-12 helicopter. The prototype Umbaugh U-17, built by Fairchild Engine and Airplane Corporation of Hagerstown, Maryland, flew in August 1959. Further test flights were conducted by chief pilot Ken Hayden and former Pitcairn Autogiro Company pilot Slim Soule. The prototype exhibited stability problems due to its single rudder and minimal T-tail horizontal stabilizer positioned on a boom behind the pusher propeller.
Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. The Zlin Z-50 is a aerobatic sports plane built by the Czechoslovakian company Zlin Aircraft.In autumn 1973 it was decided in Moravan Otrokovice to develop a new single seat aerobatic airplane. The design team was headed by Jan Mikula, a noted Czech designer. During the design phase, computer optimization was used to achieve the desired aerodynamic characteristics. The principal goal was to determine the optimum engine and propeller combination for this aircraft. Designers settled on the Lycoming AIO-540 D4B5 horizontally-opposed six-cylinder piston engine, rated at 194 kW (260 HP), driving a three-blade Hartzell constant speed propeller.
Rodrig Goliescu (1882 1942) was a Romanian inventor, engineer, and Lieutenant, who built the avioplan, the first airplane with a tubular fuselage.The model, with a length of 1.2 m was successfully tested in 1909, having a take off angle of 30 degrees. The originality of this aircraft was the shape of the fuselage, designed for minimum drag and acting as a tube fan, similar to the way the modern vertical take off aircraft and helicopters are designed. This shape reduced drag and increased the efficiency of the propeller. Helped by the Minister of Education, Spiru Haret, who also helped Aurel Vlaicu, in 1909 he went to France to acquire an engine for his aircraft. In Paris he sent a survey "Laws of air dynamics" to the French Academy, study that was published in "La France automobile et aérienne" magazine, on 15 May 1909.
High Quality Content by WIKIPEDIA articles! The core of every vortex can be considered to contain a vortex line, and every particle in the vortex can be considered to be circulating around the vortex line. Vortex lines can start and end at the boundary of the fluid or form closed loops. They cannot start or end in the fluid. (See Helmholtz's theorems.) Vortices readily deflect and attach themselves to a solid surface. For example, a vortex usually forms ahead of the propeller disk or jet engine of a slow-moving airplane.