A well known company Pipistrel d.o.o. from Ajdovščina Slovenia, is after years of development producing an electric powered aircraft, where the design is based on gliders which can fly, or better, glide considerable distances without an engine purely by its basic aerodynamic properties. And as such are very suitable for a fully electric power train.
This aircraft by Pipistrel (translation: Bat, Latin: Pipistrellus) is especially developed for the flight training role where students need to practice touch and goes countless times until they are proficient. This type of training results in hours flying in the traffic pattern and with the Alpha Electro noise and emissions are kept to the absolute minimum.
Mar 2022: Pipistrel has been acquired by Textron for their eAviation product line. Facilities in Europe will remain. Read more at AVweb: Pipistrel Sold.
The serially produced "Alpha Electro" aircraft shares an airframe which has been proven as excellent by hundreds of Pipistrel aircraft flying by their owners worldwide. The electric power train is operated with one simple lever, thus enabling the student to focus on learning piloting skills.
With the smart fast charger, using the ALPHA Electro is as simple as charging a mobile phone. Even if you only fly for fun and not in the business of training future generations of pilots, the almost silent cockpit, the immediate response of the power train and the lack of exhaust emissions will make you feel the spirit of pioneering electric flight.
Their prototype WATTsUP was developed in partnership with Siemens AG, who provided the electric main propulsion components, and represents the next generation of Pipistrels electric aircraft. Every single element of aircraft has been refined to be lighter, more efficient and more reliable. This proof of concept was developed in 2014.
The 21 kWh battery pack is dual-redundant and designed to be either quickly replaceable within minutes or fast charged in less than one hour, thanks to the next generation Battery Management technology developed by the company.
The airframe uses the same proven features from hundreds of Pipistrel aircraft flying worldwide. More info on the Wattsup website.
The first flight of this aircraft was in August, 2014. EAA reported on that flight, click here for the story.
As of AERO 2018 there had been 18 aircraft delivered around the world with 80 on order, this is a success for the company. Most of them are destined for flight schools. Should you desire a test flight we advise you to contact a distributor in your area. Early 2020, some 60 Alpha Electro aircraft have been delivered.
The Alpha Electro has air cooled batteries and as such has had problems in California with higher air ambient temperatures. The Velis, see below, solved that with liquid cooling (50/50).
In 2020 the Alpha Electro obtained an EASA Type Certificate (EASA.A.573 TCDS), and its name was changed into Velis Electro. Some of the major configuration changes are that the aircraft will be equipped with the wings of the Virus 121 SW and also have a larger capacity battery of 24.8 kWh. The endurance is 50 minutes with 10 minutes reserve... Maximum takeoff power is allowed for 90 seconds.
In the Velis the motor and battery are liquid cooled. The battery, like the Alpha Electro, consists of two packs: one in the back and one in front of the cabin. These continue to be the weak point in energy density and service longevity too. The technology used is lithium-polymer (Alpha Electro) lithium-ion (Velis) with a density of about 200 Wh/kg. Which is what you can expect from that chemistry.
Sep 2020, AVweb: The Velis has applied for some records for electric aircraft. These were flown in Aug/Sep 2020, read more in this article.
Jan 2022, Avweb brought us an update and a flight test concluding that it was cool but not for the US (or any) market.
The following short list of specifications were available at AERO:
Pipistrel | Alpha Electro | Velis Electro |
Electric Motor | PEM 60MVLC air cooled | E-811 liquid cooled 22,7 kg (50 lbs) |
Takeoff Power (one minute) | 60 kW (81.6 hp) | 57,6 kW (77 hp) |
Continuous | 50 kW @ 2100 - 2400 RPM | 49.2 kW (66 hp) @ 2350 - 2500 RPM |
Cruise | ~18 kW | 35 kW |
Propeller | Three Bladed | P-812-164-F3A |
Battery Packs | 2, removable and each weighs around 60 kg | 2 packs, each 73 kg |
Energy Content | 21 kWh+ | 24,8 kWh |
Empty Weight | 368 kg | 428 kg |
Max Weight | 473 - 550 kg (1213 lbs) | 600 kg (1302 lbs) |
Stall Speed | 42 KCAS | |
TBO engine | 2000 hours | Rebuild @ 300 hours |
'Fuel' cost | less than $25 / €20 per hour | Charger cost and Battery replacement not included |
Endurance | 1 hour plus 30 minute reserve | 50 minutes plus 10 reserve |
As the Alpha Electro is based on the same airframe as the Alpha Trainer, most specifications apply too. Notable differences are the empty weight which is significantly higher and as a result, the stall speed.
Please note that the replacement cost for the two battery packs are not included into the hourly cost as is the initial cost for the recharging unit, which is close to €10.000. They expect two battery replacements every 2000 hours costing as much as a Rotax overhaul, around 20.000 usd. But no mention of what to do with the worn out batteries, chemical fire hazard and all.
Pipistrel d.o.o. can be contacted at the addresses below:
PIPISTREL d.o.o. |
GORIŠKA CESTA 50a |
SI – 5270 Ajdovščina, Slovenia |
+386 5 36 63 873 |
[email protected] |
www.pipistrel-aircraft.com |