HI Uplift: Airbus Racer tech aims ‘to transform civil heli missions’

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by Mike Stones

26 July 2024

The Airbus Air Racer demonstrator promises more speed and lower fuel consumption and noise.

Imagine a civil helicopter cruising at nearly 300mph (277kts). Think of an aircraft fitted with two pusher propellers and a box-wing design; that can cut fuel consumption by 20% compared with similar-sized rotorcraft. Oh, and add in a seating capacity of 10, significantly lower CO2 emissions and a lower noise footprint than conventional designs.

The result of that imagining could be close to the Airbus Racer – a high-speed helicopter demonstrator, now undergoing flight trials with Airbus. To be clear, this is a demonstrator aircraft and not destined for production. But the manufacturer believes the technology probed by this design has the potential to transform civil helicopter missions. It is on a mission to turn those dreams to reality – and the early signs are encouraging.

The Racer completed its maiden flight of about 30 minutes in April at Airbus’s Marignane facility in southern France. Less than two months later, on June 21st, the hybrid aircraft exceeded its level speed target of 253mph (220kts) after reaching 261mph (227kts) in its initial configuration. In just seven flights, logging about nine hours of flight testing, almost all the flight envelope has been explored, according to the manufacturer.

Fuel savings of 20%

Fuel savings of around 20%, compared with current generation helicopters in the same maximum take-off weight category, will be delivered thanks to aerodynamic optimisation and an innovative eco-mode propulsion system, says Airbus.

Developed with Safran Helicopter Engines, the hybrid-electrical eco-mode system allows one of the two Aneto-1X engines, both powering pusher propellors, to be paused while in cruise flight. This enables lower fuel consumption and contributes to lower CO2 emissions.

A key contributor to lift is the demonstrator’s box-wing design. By providing 40% of the total lift, the wing is said to take some load off the main rotor, reducing dynamic loads and vibrations. The performance of the wing is also optimised in all phases of flight by the use of flaps placed on the trailing edge, contributing to lower fuel consumption.

Viable and affordable aircraft

Tomasz Krysinski, vice-president Research and Innovation, Airbus Helicopters underlines the manufacturer’s commitment to eventually developing the technology being pioneered by the Racer into a viable and affordable commercial aircraft. “We are not a research centre – everything we do has a final destination to achieve a product,” he tells Helicopter Investor at the Farnborough International Air Show this week. But first the manufacturer must demonstrate the new helicopter technology to what it calls Technology Readiness Level Number 6. (NASA defines this as “System/subsystem model or prototype demonstration in a relevant environment (ground or space).”

Nevertheless, Krysinski expects the aircraft which eventually embodies the Racer technology to have a transformative role in both civil and military applications. “We can already fly the Racer at 227 knots and we can perhaps achieve 50 knots more than that,” he tells us. “The aircraft is not pressurised and we don’t have a tilting mechanism.”

It all adds up to a winning recipe for civil helicopter operations whenever speed and time are critical – including emergency service missions and emergency medical service (EMS) operations, according to Airbus. “In one Golden Hour [the critical period to treat trauma care patients] you can cover twice the ground covered by a normal helicopter,” says Krysinski. “That’s because you can fly 50% quicker than normal helicopters, so you can cover double the service.” The aircraft’s speed should also mean EMS operators need fewer helicopters and fewer bases from which to operate them. “So, it delivers a lot of advantages in this role,” he adds.

Search and rescue missions

It is not just EMS missions where Krysinski believes the new hybrid design “will open the doors”. He foresees roles in both search and rescue (SAR) missions and VIP transport flights.

Fast as the commercial variant of the Racer promises to be, does he expect competition from tiltrotor aircraft such as Leonardo’s AW609? (Carrying two crew and nine passengers, this equally novel aircraft claims a maximum cruise speed of 311mph (270kts).

Krysinski refuses to be drawn on comparisons between the Racer and other manufacturers’ designs. But he does allow himself this observation: “I can tell you that aeronautics does not like complexity: something simple like a helicopter with one main rotor and just two propellors with an integrated drive. It’s not more complicated than a helicopter. For me, simplicity is a key driver for rotary wing.”

Cost efficiency is also important, he adds. “At any moment, technology must meet the market.”

90 patent applications

The early flight test results have impressed the boss too. Bruno Even, CEO of Airbus Helicopters, praised both the partnership leading up to the first test flights and the technical achievement. “This achievement in such a short space of time is really a testimony to the hard work of our 40 partners in 13 European countries to bring all of this innovation to flight,” said Even. The Racer is being developed as part of the European Research Clean Sky 2 project. More than 90 patent applications were involved in the helicopter’s design.

“On top of its performance, the aircraft’s aerodynamic behaviour and stability are promising,” said Even. “We are all looking forward to the next phase of flight testing, especially the eco-mode which will enable us to shut down one engine in forward flight, thus reducing fuel consumption, and lowering the CO2 emissions.”

The new aircraft is not the first of its lineage. The design builds upon the aerodynamic configuration developed by the Airbus Helicopters X3 technology demonstrator. Back in 2013 this aircraft broke three speed records and pushed the limits for a helicopter by reaching 472 km/h.

Meanwhile, Hervé Jammayrac, chief flight test pilot describes the Racer as being just like a conventional helicopter to fly. Equipped with the regular controls – collective pitch control, cyclic pitch control and the antitorque pedals or tail rotor control, the Racer, so far, appears to demand no special skills from her pilots. One of the few control differences are controls on the cyclic which control the pusher propellors. That promises another cost reduction factor for the operators of the future.

When flight testing the Racer resumes after the summer break, evaluations will focus on single-engine operations, key to delivering 20% fuel reductions, and finalising the aircraft’s flight envelope.

So, while the Racer remains a demonstrator aircraft project, Airbus believes the technology it pioneers – promising more speed, cost savings and lower emissions – will help a new helicopter one day secure its place in both civil and military markets.