What is an X3 Helicopter?

Engineers at Eurocopter set out to prove that it was possible to create a ‘low cost’ helicopter that could attain high speeds. This summer the company brought its new ‘proof of concept’ X3 helicopter to tour the United States. One year previously, the X3 had flown at 232 knots in level flight at 80% of available power – substantially faster than a conventional helicopter’s 150-160 knots. Speaking in Grand Prairie, Texas at the X3’s U.S. debut in June, Dr. Lutz Bertling, Eurocopter’s president and CEO explained, “the idea was to combine the fast cruising speeds of an airplane with the hover flight capabilities of a helicopter, to create a revolutionary new aircraft.”

Eurocopter expects the new helicopter type will find uses in long-distance search and rescue, coast guard, border patrol, ­passenger transportation, off-shore airlift and inter-city shuttle services. Designed to be “affordably fast”, the company believes the X3 proves that a new generation of hybrid helicopters can deliver a 50% increase in cruising speed with only a 25% increase in total cost of ownership, making the hybrid configuration well-suited for operations with long transit times.

Eurocopter says the X3  has the same handling as a conventional helicopter. Dr. Bertling noted, “out of personal experience, transition from flight to hover is as easy as conventional rotary-wing aircraft.”

Hervé Jammayrac, a Eurocopter test pilot said other pilots would have little difficulty adapting to the new aircraft type. “It’s very intuitive,” he commented.

The aircraft itself is based on proven technology, combining the airframe of a Eurocopter Dauphin with NH90 turbines, EC175 gearbox central module, and trim actuator motors from the EC145 and the EC155’s five-bladed rotor. The use of existing components in the X3 design suggests that Eurocopter may be able to market both high-speed and conventional versions of some machines, bringing down the costs of training, maintenance and spares inventory. “There could be a hybrid option for several of our aircraft,” Dr. Bertling said.

The top speed of conventional helicopters has been limited by the difference between the relative speeds of the advancing and retreating blades, as one builds up drag and the other stalls. The side-mounted propellers on the X3 ‘unload’ the main rotor so it can run at reduced RPM. That lower rotor speed also reduces lift, so at cruising speed, the wings provide about 40% lift.

“Can we get it tomorrow?” is often the first question, according to Dr. Bertling, but the answer is no. It could take 10 years for a commercial version to reach the market.

However, the American Helicopter Society is very intrigued with this new proto­type and this year awarded its coveted Howard Hughes Award for Helicopter Technology Improvement to Eurocopter for its innovative machine. With the X3 demonstrator exceeding all company expectations during flight tests performed since 2010, the company is now pursuing hybrid applications, these range from long-distance search and rescue (SAR), coast guard, border patrol and special forces operations, to inter-city passenger shuttle services, and offshore oil and gas transportation.

Richard Bray is FrontLine’s Senior Writer.
© Frontline Security 2012