Please answer the following question: Information: - Rostov-on-Don is a port city and the administrative center of Rostov Oblast and the Southern Federal District of Russia. It lies in the southeastern part of the East European Plain on the Don River, from the Sea of Azov. The southwestern suburbs of the city abut the Don River delta. Population: - Stevens Institute of Technology (SIT) is a private, coeducational research university located in Hoboken, New Jersey, United States. The university also has a satellite location in Washington, D.C.. Incorporated in 1870, it is one of the oldest technological universities in the United States, and was the first college in America solely dedicated to mechanical engineering. The campus encompasses Castle Point, the highest point in Hoboken, and several other buildings around the city. - The Bensen Aircraft Corporation was established by Dr. Igor Bensen at Raleigh-Durham International Airport in North Carolina in 1952 to develop and market a variety of helicopters and autogyros of Bensen's own design. - Igor B. Bensen (April 1, 1917 February 10, 2000) was the founder of the Bensen Aircraft, which produced a successful line of gyrogliders (rotor kites) and autogyros. He was born in Rostov-on-Don, Russia, and eventually reached the United States in 1937. He began studies at age 17 while in Belgium, won a scholarship to study in the USA three years later, and was awarded a Bachelor of Science degree in mechanical engineering from Stevens Institute of Technology in Hoboken, New Jersey in 1940, later becoming a Registered Professional Engineer. - A helicopter is a type of rotorcraft in which lift and thrust are supplied by rotors. This allows the helicopter to take off and land vertically, to hover, and to fly forward, backward, and laterally. These attributes allow helicopters to be used in congested or isolated areas where fixed-wing aircraft and many forms of VTOL (vertical takeoff and landing) aircraft cannot perform. - A rotor kite or gyrokite is an unpowered, rotary-wing aircraft. Like an autogyro or helicopter, it relies on lift created by one or more sets of rotors in order to fly. Unlike a helicopter, gyrokites and rotor kites do not have an engine powering their rotors, but while an autogyro has an engine providing forward thrust that keeps the rotor turning, a rotor kite has no engine at all, and relies on either being carried aloft and dropped from another aircraft, or by being towed into the air behind a car or boat or by use of ambient winds for the kiting. As of 2009, no country in the world requires a license to pilot such a craft. - An autogyro (from Greek + , "self-turning"), also known as gyroplane, gyrocopter, or rotaplane, is a type of rotorcraft that uses an unpowered rotor in autorotation to develop lift, and an engine-powered propeller, similar to that of a fixed-wing aircraft, to provide thrust. While similar to a helicopter rotor in appearance, the autogyro's rotor must have air flowing through the rotor disc to generate rotation. Invented by the Spanish engineer Juan de la Cierva to create an aircraft that could fly safely at slow speeds, the autogyro was first flown on 9 January 1923, at Cuatro Vientos Airfield in Madrid. De la Cierva's aircraft resembled the fixed-wing aircraft of the day, with a front-mounted engine and propeller in a tractor configuration to pull the aircraft through the air. - The Bensen B - 6 was a small rotor kite developed by Igor Bensen in the United States in the early 1950s and marketed for home building . It was a minimalist design based on Bensen 's B - 5 and consisting of little more than a seat mounted on wooden skids and with a two - blade rotor mounted on a tubular framework above it . Small fins for directional stability were mounted at the rear of the skids . The pitch of the rotors was fixed , but a handlebar allowed them to be tilted for directional control . The B - 6 was intended to be towed aloft behind a car or boat . The machine became airborne at 19 mph ( 31 km / h ) , and with 300 ft ( 90 m ) of tow - rope , could achieve a maximum altitude of 150 ft ( 46 m ) . The rope could be detached to allow the machine to autorotate to the ground , taking up to 15 minutes to do so . The machine could also become airborne in a sufficiently strong wind of around 23 mph ( 37 km / h ) . - A Bachelor of Science (Latin ', B.S., BS, B.Sc., or BSc; or, less commonly, S.B., SB, or Sc.B., from the equivalent Latin ') is an undergraduate academic degree awarded for completed courses that generally last three to five years. Given the paragraphs above, decide what entity has the relation 'subclass of' with 'aircraft'.
Answer:
bensen b-6