Airbus Helicopters details test plan to prove Racer is more than just a sprinter

Forthcoming campaigns for compound rotorcraft demonstrator include trials of eco-mode engines, low-noise approaches and long-distance flights.
Ever since Airbus Helicopters first flew its Racer demonstrator back in April 2024, the high-speed rotorcraft has been sprinting ahead.

Envelope expansion was completed in just seven flights, a speed target of 220kt (407km/h) was reached then breached – in fact, the Racer has been taken to 246kt – while the rotorcraft has also showcased its fuel-saving potential, coming in significantly ahead of target.

“We have this great maturity which is really good evidence that we have the right concept,” says newly appointed Racer chief engineer Jerome Geneix.

Building on the earlier X3 demonstrator, the Racer uses a pair of lateral pusher propellers mounted at the apex of V-shaped box-wings to achieve high-speed flight. Around 50% of the total lift in forward flight is generated by the wing, allowing the main rotor to be slowed for better efficiency.

But with 70 flight hours now in the bag – including at the hands of multiple external pilots – the Racer is facing a short pause while it is prepared for its next phase, he says.

Fuel-saving potential

This will see the installation of systems supporting the operation and testing of the so-called ‘eco-mode’ on the Racer’s Safran Helicopter Engines Aneto-1X turboshafts.

In essence, eco-mode enables one of the two powerplants to be shut down during cruise, allowing the other to run an optimal output, thus saving fuel, while still maintaining a 180kt speed.

Critically, of course, the system also allows the ‘sleeping’ engine to be rapidly restarted; Geneix says in emergencies this should be possible in under 7s.

Installation of the eco-mode technology is under way at Airbus Helicopters’ headquarters in Marignane in southern France and Geneix says “the ambition” is to have the Racer flying again before the end of the year, with eco-mode testing running through early 2027.

Racer architecture combines single main rotor with lateral propulsors mounted on V-shaped box wing. Source: Airbus Helicopters

Proving out the operation of the technology – theoretically applicable to any twin-engined helicopter in the manufacturer’s line-up – is another critical step in validating the Racer’s fuel frugality.

At the start of the programme, the goal was to demonstrate a fuel-burn reduction of 20% at 180kt cruise against a comparably sized conventional helicopter flying at 140kt.

That target has already been surpassed during flight testing, with the Racer’s low-drag profile and more efficient compound configuration enabling a 25% reduction; eco-mode promises another 15% saving, says Geneix.

Although it is not as simple as adding those two numbers together, Geneix says a final figure in the region of 30% is achievable.

“But we have to take it to the flight test to make those results a reality,” he says. “That will reveal the performance much better than estimation.”

While Geneix says the technology is “not yet at the level of maturity” where it could be applied to in-service aircraft, next year’s flight-test campaign will help to build a safety case around it, particularly around a potential engine failure.

“We have to demonstrate that we have the same level of security and safety that we show when both engines are operating,” he says.

Similarly, a future round of flight tests will also attempt to validate the Racer’s range performance, proving its credentials as a distance runner as well as a sprinter.

At the outset, 400nm (740km) was the goal “and we have been able to demonstrate and even exceed it with a full payload,” says Geneix.

But that was reached at the maximum design speed of 220kt, he notes: longer flights will be possible at the lower cruise speed and longer still if eco-mode lives up to expectations.

“This will also be part of the flight-test campaign next year – our objective is to perform a long-range flight demonstration to assess what we are able to achieve.”

Evaluations next year will include long-range flights. Source: Airbus Helicopters

Geneix will not be drawn on the range target Airbus Helicopters has in mind but says it is a “significant increase” on the 400nm baseline and goes beyond “a marginal 10% improvement”.

Recent trials also saw nap-of-the-earth flights conducted from the Cazaux test centre in southern France, with military pilots also performing the tactical-style sorties.

A reference flight with a conventional helicopter recorded an average speed of 60kt for the mission, while the Racer covered it at an average of 150kt.

Geneix says the delta between the two aircraft is driven by the Racer’s level flight attitude when accelerating or decelerating – a product of its configuration, which means, unlike a conventional helicopter, the nose does not need to be raised or lowered during these manoeuvres.

“It’s not only about the raw speed, it’s the capacity to manage your speed independently from the attitude of the aircraft,” he says.

“From the pilot’s perspective there is a decrease in workload and therefore they can adapt the speed to the environment more easily than in a conventional rotorcraft.”

The Racer has now been flown by military pilots from France, Germany and Italy, plus other nations, he notes.

Arguably, there is also an increased emphasis on military applications for the underlying technology: Airbus Helicopters is participating in a NATO project to develop a next-generation rotorcraft, with a Racer-derived design likely to form part of its bid.

And Airbus Helicopters chief executive Mathieu Louvot has previously said that it would not develop a high-speed rotorcraft without military funding.

Improved handling characteristics have been showcased during test campaign. Source: Airbus Helicopters

Despite that 246kt figure dominating many of the headlines, Geneix is keen to emphasise that the Racer is more than simply about speed: many of its other attributes are just as likely to shape any future design, he says,

In fact, he says it is better to think of the Racer as “an enhanced rotorcraft” rather than one simply capable of flying fast.

Indeed, the feedback from pilots is that many of the Racer’s other attributes – handling characteristics like 2g turns at 200kt, its acceleration, a climb rate of 3,600ft/min – represent the “added value” the configuration brings.

“A kind of conclusion from this preliminary feedback… is that speed is not the goal: speed is a means of bringing benefits to the mission and all these other additional figures contribute to having an enhanced rotorcraft.”

Unexpected benefits have also been discovered through the test campaign, he says, including safety – autorotations are easier, and the Racer is better able to exit from vortex ring state than a conventional helicopter – alongside lower than predicted maintenance costs through a reduction in load on the dynamic components.

Acoustic performance

In the meantime, the Racer will continue flying. Aside from the eco-mode and long-range trials planned for next year, Airbus Helicopters plans to complete testing of the

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