A number of companies are developing electric power plants for aircraft, basically for powered gliders and small ultralight aircraft. In most of these designs the power plant is of secondary importance and the aircraft can fly, or better, glide considerable distances without an engine purely by its basic aerodynamic properties.
Developments are in progress to electrify some every day general aviation class aircraft or even new designs. Because of many limitations to overcome, large scale applications will not come any time soon. The main problem is energy storage: liquid fuel (Mogas, AVgas or Jet fuel) has the highest energy density per weight, which is very hard to beat, except for nuclear fission or fusion. This will limit the range of any aircraft trying to fly any considerable amount of time or distance with a worthwhile payload.
The first page became too long so we continue the list here.
NASA uses a Tecnam P2006 airframe, installed batteries in the second row and two electric motors on the wings and called it the X-57 Maxwell. It can fly 1 hour and covers a distance of 100 nm. The cabin seats two persons. Estimated cost for the aircraft is 2 million USD. At Oshkosh 2021 AirVenture Tecnam announced they sold two P2006 aircraft to NASA.
2021: Tecnam is working with Rolls-Royce Electrical on the electric propulsion system for the P-Volt, which is an electric-powered version of the 11-seat, piston-engine P2012 Traveller. Current range is 100 miles with batteries at 80% of their service life. Tecnam is working together with Rolls-Royce but Tecnam has not decided on the power train.
The U.K based company is developing the eFlyer (cost ~500000 USD!), two seat (four seat in the works) since 2014. The engine used in these aircraft is from Siemens. More information on the Bye Aerospace website. Their next version, the e-Flyer 2, is a three hour airplane but technically 1 to 1,3 hour. The motor is 150 hp with a rate of climb of 1200 fpm. Operational cost per hour seems low, I guess they 'forgot' the battery replacement and charger cost.
At Air-Venture 21 Bye gave an update on the progress of their electric trainer. See more of that in the video from AVweb on YouTube: Bye Trainer Update. In that video we can see battery packs behind and in front of the cabin.
2021: Bye now explorers a twin e-aircraft for it potential customers. From the company: eFlyer 800: a project responsive to "growing demands for regional all-electric airplanes with significantly reduced operating costs, plus increased capacity and utility." Bye is using, or is planning to use Li-S (Lithium-Sulfur) batteries for energy storage. Read more on that in our article about energy storage.
Their estimated performance for the low wing eight place with wing mounted electric motors, prominent winglets, and a T-tail includes up to a 320 kts cruise speed offers a 35000 ft ceiling, and a 500 nm range with 45 minute IFR reserves at normal cruise speed of 280 knots and a maximum payload of 1540 pounds. More on the story from AOPA: Bye twin 8 seat aircraft.
A 2011 startup UK company is developing an electric Nemesis NXT airframe together with Roll-Royce. This airframe was one of the few still around and suitable to contain the battery pack in the fuselage. Propulsion is with three (!) electric motors, 750R AC from YASA, driving a single MT constant speed propeller.
The battery pack consist of three channels, one for each motor. Total number of cells is 6000 at a weight of 2600 lbs / 1180 kg and has no protective metal box as in cars. It weighs more than the rest of the aircraft. The system also includes three DC/AC converters to feed the motors. For cooling a pump and heat exchanger with a non-conductive coolant as this runs within and through the battery.
Endurance at maximum power is 6 minutes(!), with partial power takeoffs expect 10 minutes over the airport. More information at Avweb Inside.
Sep 2021: The aircraft took flight this month and flew for about 15 minutes. It took them 10 years to get this far. The powertrain is 400 kW. The company claims that aviation emitted 1 Gigaton of CO2 in 2019, what they do not say is that its only 0,4 ppm of all CO2 in the atmosphere. More information in the article from CNBC News: Rolls-Royce Electric Aircraft.
This is not really an aircraft or manufacturer but its a wing suit driven by two electric turbines and stays aloft for five (5) minutes, created by Peter Salzmann and BMW. In the test flight the 'pilot' was dropped from an altitude of 10000 feet and flew over the Alps. AVweb has the story: Electric WingSuit. Nice try, but of no real practical use.
Aeromarine LSA from Lakeland Florida is developing, designing, experimenting with an electric version of their Merlin PSA (one seat Personal Sport Aircraft). They expect a 93 mph (80 kts) cruise with a 1 hour endurance. The custom designed electric motor weighs 12 kg with 55 kW output power. The battery is a LiPo Cobalt chemistry with a capacity of 65 Ah. Recharging is done in 2,5 hours with a life expectancy of 2000 cycles.
2021: The above specifications have been removed from the site and only a page has been left stating that electric power works for very light and low-energy aircraft. They do offer a V-twin two cylinder hybrid drive where the electric motor is mounted on the propeller shaft of the gear box. See the next video from Light Sport and Ultralight Flyer about the 60 HP V-Twin Hybrid.
Plus some other comments and specifications about the Zigolo trike e-powered ultralight. Which are: Battery Packs: 2 x 3.1 kWh 14S/20P/15 kg, 60 Ah, Motor: 20 kW continuous, 28 kW peak, low noise, low RPM; Controller: 28 kW continuous/ 40 kW peak; Advanced Drive Interface for an extensive display and recording of flight parameters and a 3-blade composite propeller. The charger is 15 A/ 980 W. More info about the Zigolo.
2021: The company now offers some more information about their ventures into electric aviation on the website, see the link: Electrolite. Development is still going on.
A very remarkable item is that the aircraft has THREE electric motors. One in the nose and one inside the wing in front of each aileron! Its called DEP-OD or 'Distributed Electric Power - On Demand'. Now thats going to be very interesting. See more in the video from Light Sport and Ultralight Flyer about the Merlin Electrolite
2021: A kit ultralight aircraft (part 103) and 1000 of these have been constructed until today, their e-aircraft has an electric engine (30 lbs) and a system with 2, 3 or 4 battery units (35 lbs a piece). The four pack runs the plane for an hour at an economical cruise speed (45 - 63 mph) at 1400 propeller RPM. When performing take-offs and landings in the pattern the endurance is reduced in half. More info at the website of u-fly-it dot com.
The motor (maximum 2000 RPM), cable harness and controller costs 4500 USD and each battery unit with a charger costs around 2500 USD and it takes around 8 hours to charge a unit, although you can leave the batteries in the aircraft and charge all of them with one charger, then it will take 4 x 8 = 32 hours for a complete charge. Battery life is some 500 complete cycles. That comes to 10000 USD for 500 hours of flight or 20 USD per hour (at 50 mph IAS) to replace the batteries alone, as long as they or the controller do not fail sooner.
Yuneec International E430 was in 2009 developing the E430 which is a twin seat, single engine, LSA class aircraft with a significant difference to every commercially available plane that has come before it – it is entirely electric. The lightweight composite construction E430 charges in three hours from a domestic 230 volt power point and runs for two and half hours on a charge.
Wing Span: 13.8 m (45.2 ft), Fuselage Length: 6.68 m (21.9 ft), Empty Weight:178 kg (392 lbs) (No Battery), Maximum Takeoff Weight: 430 kg (946 lbs), Motor Output: 40 kW (54 hp) @ 2,450 RPM, Battery Type: Lithium Polymer, Battery Weight: 72 kg (158.5 lbs) (6 Packs). Information from NewAtlas Yuneec.Written by EAI.