Airbus Group and Siemens plan to develop prototypes jointly for various propulsion systems with power classes ranging from a few 100 kilowatts up to 10 and more megawatts, i.e. for short, local trips with aircraft below 100 seats, helicopters or UAVs up to classic short and medium-range journeys.

Airbus Group and Siemens have signed a collaboration agreement in the field of hybrid electric propulsion. In doing so, the Chief Executive Officers (CEO) of both companies, Tom Enders and Joe Kaeser, have launched a major joint project towards the electrification of aviation with the goal of demonstrating the technical feasibility of various hybrid/electric propulsion systems by 2020.

Both companies will make significant contributions into the project and have sourced a team of around 200 employees to advance European leadership in innovation and the development of electrically-powered aircraft.

Electric and electric-hybrid flight represent some of the biggest industrial challenges of our time, aiming at zero-emissions aviation. The progress we have achieved in this arena, together with our industrial and governmental partners, in only a few years is breath-taking, culminating in last year’s channel crossing of our all-electric E-Fan aircraft. [Earlier post.] We believe that by 2030 passenger aircraft below 100 seats could be propelled by hybrid propulsion systems and we are determined to explore this possibility together with world-class partners like Siemens. —Tom Enders, CEO of Airbus Group







Airbus E-Fan on its channel flight. The all-electric E-Fan made the 74km (46-mile) crossing from Lydd, England to Calais, France in about 37 minutes. Click to enlarge.

Hybrid-electric propulsion systems can significantly reduce fuel consumption of aircraft and reduce noise. European emissions targets aim for a 75% reduction of CO 2 emissions by 2050 compared to the values for the year 2000. These ambitious goals cannot be achieved by conventional technologies.



An electric motor from the Electric Aircraft Unit at Siemens Corporate Technology features a power/weight ratio of 5 kW/kg. At a weight of 50 kg, the motor delivers a continuous output of about 260 kW—five times more than comparable drive systems. Click to enlarge.

Both companies together with Austria’s Diamond Aircraft initially presented a hybrid aircraft back in 2011. Since then, Siemens has been developing an electric motor for aircraft which supplies five times as much power while retaining the same weight.

To develop the motor, Siemens experts from the Large Drives Division and from Corporate Technology tested all the components from previous motors and optimized them as far as was technically feasible. In this way, they were able to cut the weight of the motor’s end shield by more than half, reducing it from 10.5 kg to 4.9 kg.

Made of aluminum, this component supports the motor bearing and the propeller, which is fixed to a continuous drive shaft without a gearbox in between.

A cobalt-iron alloy in the stator results in high magnetizability, and the permanent magnets of the rotor are arranged in a Halbach array (an arrangement of permanent magnets that augments the magnetic field on one side of the array while cancelling the field to near zero on the other side).

This means that four magnets are positioned next to one another in such a way that the orientation of each field is in a different direction. One result of this is that magnetic flux can be optimally directed with a minimal use of material. A new cooling concept has also helped reduce weight.

The motor uses direct-cooled conductors and directly discharges the loss of copper to an electrically non-conductive cooling liquid.

Airbus Group has been gathering operational experience with electrically powered aircraft since 2014 with the E-Fan, a full electric two-seater dedicated to training pilots. This success has been achieved together with various industrial partners and steadfast support of the French government. (Earlier post.)

Airbus Group intends to accelerate with the extended capabilities of the planned E-Aircraft System House at Ottobrunn/Taufkirchen site the development of components and system technologies.

Siemens is determined to establish hybrid-electric propulsion systems for aircraft as a future business. The partners have agreed to collaborate exclusively in selected development areas. In parallel, both partners will continue to work together with their current partners for small aircraft with fewer than 20 seats.