Eurocopter X³

Airbus Helicopters

Company type	Subsidiary
Industry	Aerospace
Predecessor	Eurocopter
Headquarters	France
Products	Helicopters, including experimental models like the Eurocopter X³
Parent	Airbus

The Eurocopter X³ (pronounced X-Cubed) is an experimental high-speed compound helicopter that has been retired, developed by Airbus Helicopters (formerly known as Eurocopter). Serving as a technology demonstrator for the "high-speed, long-range hybrid helicopter" (H³) concept, the X³ achieved an unofficial helicopter speed record by reaching in level flight on 7 June 2013. In June 2014, the aircraft was placed on display at a French aviation museum located in Saint-Victoret.

Technology

Derived from the Eurocopter AS365 Dauphin, the X³ incorporates short-span wings equipped with tractor propellers that counteract the torque produced by the main rotor through variable pitch settings. Unlike traditional helicopters that use tail rotors to manage torque, these tractor propellers are mechanically driven by the two main turboshaft engines, which also power a five-bladed main rotor sourced from a Eurocopter EC155.

Pilots have noted that the X³ exhibits smooth handling characteristics despite lacking both passive and active anti-vibration systems. Furthermore, it can operate without stability augmentation systems, differentiating it from competitors like the Sikorsky X2. The design concept focuses on high-speed flight by reducing rotor speed by roughly 15% to minimize drag and prevent retreating blade stall. At higher velocities, the small wing generates between 40% and 80% of the lift.

In hover mode, the X³ can maintain a pitch attitude ranging from −10 to +15 degrees and bank angles up to 40 degrees, with flight capability extending to bank angles between 120 and 140 degrees. Testing demonstrated a climb rate of 5,500 feet per minute and sustained turns at 2G forces while traveling at 210 knots.

Performance

The X³'s maiden flight occurred on 6 September 2010 at the French Direction générale de l'armement facility situated at Istres-Le Tubé Air Base.

On 12 May 2011, the aircraft demonstrated a speed of , utilizing less than 80% of its power capacity.

In May 2012, Eurocopter’s X³ development team was honored with the American Helicopter Society's Howard Hughes Award for Outstanding Improvement in Helicopter Technology.

During the summer of 2012, Eurocopter presented the X³ in the United States, accumulating 55 flight hours and providing opportunities for both commercial and military operators to experience its capabilities firsthand.

Equipped with an aerodynamic fairing on the rotor head, the X³ achieved speeds of in level flight and in a shallow dive on 7 June 2013. This performance surpassed the unofficial speed record set by the Sikorsky X2 in September 2010, establishing the X³ as the fastest non-jet augmented compound helicopter worldwide.

Variants

Eurocopter anticipated introducing a production H³ model by 2020 and expressed interest in integrating H³ technology within the U.S. Future Vertical Lift program. Initially, EADS North America submitted a proposal for the U.S. Army’s Joint Multi Role (JMR) program but later withdrew due to elevated costs and concerns regarding intellectual property transfer related to the X³. Subsequently, Eurocopter redirected efforts toward the Armed Aerial Scout (AAS) program, which was eventually cancelled; they were not selected for JMR.

Potential applications identified for X³ technology include offshore oil industry operations and Search and rescue. Under the European Union’s €4 billion ($5.44 billion) Clean Sky 2 research initiative, an unpressurized compound helicopter variant called LifeRCraft was proposed as a high-speed rotorcraft demonstrator.

In 2014, the original X³ prototype was transferred to the Musée de l’air et de l’espace where it remains on public display.

RACER

The Airbus RACER (Rapid And Cost-Effective Rotorcraft) was introduced during the June 2017 Paris air show. The project scheduled its final assembly for 2019, with the maiden flight anticipated in 2020. Designed to cruise at speeds up to , the RACER targets a 25% reduction in operational costs per distance compared to traditional helicopter models.

Specifications

Among its notable attributes is a five-blade main rotor, adapted from the Eurocopter EC155, complemented by two tractor propellers powered by Rolls-Royce Turbomeca RTM322 turboshaft engines. This configuration enables a top speed of 255 knots and a cruising velocity of 407 km/h. The aircraft has a maximum takeoff weight of 5,200 kg, can reach an altitude ceiling of 3,810 meters, and boasts a climb rate of 5,500 feet per minute.

External links

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• Video X³
• Video X³, Cockpit
• Making of
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