The Manzolini Libellula was a 1950s Italian co-axial twin-rotor helicopter designed by Ettore Manzolini. "Libellula" is the Italian word for "Dragonfly". Design and development Ettore Manzolini established a company in Rome, Italy to develop a helicopter he had designed. The design was the Manzolini Libellula an unusual co-axial helicopter. The co-axial arrangement eliminating the need for an anti-torque rotor allowed the helicopter to have a twin fin arrangement. The Libellula (Registered I-MANZ) first flew on 7 January 1952. An improved version was the single-seat Libellula II which went on to gain Italian certification on 15 October 1962. A three-seater version (the Libellula III) was built and a four-seat Libellula IV was planned but Manzolini stopped development in the late 1960s. Variants Libellula Prototype, one built. Libellula II Prototype single-seat version powered by a 75kW (101hp) Walter Minor 4-III engine, one built. Libellula III Prototype two-seat version powered by a 104kW (140hp) Walter M 332 engine, one built but not flown. Libellula IV Proposed four-seat version powered by a 236kW (317shp) Allison 250-CT18 turboshaft, not built. Specifications (Libellula II) References Apostolo, Giorgio. The Illustrated Encyclopedia of Helicopters. New York: Bonanza Books, 1984. Pg.123 . External links https://www.webcitation.org/query?url=http://www.geocities.com/CapeCanaveral/Launchpad/5249/manzolini.htm&date=2009-10-25+15:56:04 1950s Italian helicopters 1950s Italian civil utility aircraft Aircraft first flown in 1952 Single-engined piston helicopters