After decades of churning out updated versions of helicopters that first rolled out in the 1960s and 1970s, aerospace manufacturers are finally starting to look at new forms of small vertical take-off and landing (VTOL) craft as several companies try to pair electric energy sources with new propeller layouts. Airbus Helicopters is one such company, and this month it completed a full-scale test of the propulsion system for its CityAirbus concept — a small eight-rotor VTOL craft designed for cities.
Still in engineering and prototype build stages, the CityAirbus envisions an electrically powered four-passenger craft meant for short flights — from an airport on the outskirts of a major city to a city center, for instance — powered by 100-kW Siemens electric motors for lift and for forward flight, drawing juice from a 140-kWh battery. The quad-fairing design uses a total of eight propellers and promises a much lower acoustic footprint, according to Airbus, in addition to greater safety and stability.
“We now have a better understanding of the performance of CityAirbus’ innovative electric propulsion system, which we will continue to mature through rigorous testing while beginning the assembly of the full-scale CityAirbus flight demonstrator,” said Marius Bebesel, CityAirbus chief engineer.
Airbus’ take on an electric VTOL craft envisions an eight-rotor design for lift — two in each fairing, mimicking toy drones — which is the direction that a number of startups have also taken.
What the CityAirbus does not promise, at least not right away, is autonomous operation which is what some competitors are currently aiming for; the VTOL craft will first be flown by a pilot for certification purposes, even though Airbus eventually wants the craft to be capable of autonomous flight.
Speaking of flight, the CityAirbus is expected to take to the air for the first time at the end of 2018, with the first test expected to be piloted by remote.
Range anxiety in cars is one thing, but when it comes to helicopter-like craft it’s quite another, and the same thing goes for autonomous tech. The biggest question with this electric VTOL craft and others likely won’t be airworthiness, but the capacities of their batteries, as well as their recharging time; the autonomous tech will come later.
One of the questions that these craft will have to answer is whether passengers will trust autonomous piloting software in an electric craft of this type. This, more so than battery tech, will determine if there’s a need for VTOL aircraft of this type to be autonomous.