This airplane paper model is a Eurocpter X3 helicopter, designed by original site. The Eurocopter X3 (X-Cubed) is an experimental high-speed compound helicopter under development by Eurocopter. In May 2012 it demonstrated a speed of 232 knots (267 mph; 430 km/h).
The X3 demonstrator is based on a Eurocopter EC155 helicopter with the addition of short span wings each fitted with a tractor propeller. The tractor propellers are gear driven from the two main turboshaft engines which also drive the five-bladed main rotor. The helicopter is designed to prove the concept of a high-speed helicopter which depends on the slowing down of the rotor speed to avoid drag from the advancing blade tip, and to avoid retreating blade stall by unloading the rotor while a small wing is intended to provide up to 80% lift instead.
The X3 first flew on 6 September 2010 from French Délégation Générale de l'Armement facility at Istres-Le Tubé Air Base. On 12 May 2011 the X3 flew at a speed of 430 km/h (267 mph) for several minutes. Eurocopter intends to demonstrate the X3 in the USA in summer 2012. A product using X3 technology may come in 2020. [Source: Wiki]
- Crew: 2
- Powerplant: 2 × Rolls-Royce Turbomeca RTM322 turboshaft engines, 1,693 kW (2,270 hp) each
- Propellers: 2-bladed five bladed tractor propellers gear driven off main engines.
- Maximum speed: 430 km/h; 267 mph (232 kn) at 2,500 m (8,202 ft)
- Cruising speed: 407 km/h (253 mph; 220 kn)
- Service ceiling: 3,810 m (12,500 ft)
- Rate of climb: 25 m/s (5,000 ft/min)