Pipistrel aircraft electric propulsion systems started way back in 2004 with the first “primitive” designs by today’s standards being designed and tested, in these times with batteries that weighed upwards of 500 kgs!
Although lithium batteries appeared to be a new introduction to the battery market they were originally experimented with in 1912 but it was not until the 1970’s that the first commercially available lithium batteries came on the market.
These were very small batteries primarily designed for the photographic industry. In 1985 a rechargeable and more stable version of the very first lithium batteries was commercialized by Sony and released publicly in 1991.
In 1997 the first lithium polymer batteries were introduced followed by lithium ion batteries and eventually the first batteries that could be used in aircraft around 2005-2006.
Seizing on these battery improvements, Pipistrel released the first two seat electric aircraft to fly in 2007.
The TAURUS Electro was accepted by the market with strong sales from 2007 through to late 2011. In 2012 Pipistrel released the second generation of the electric propulsion system and the aircraft was called the Taurus Electro G2 (G2, standing for generation 2 of the design). In 2018 Pipistrel released the Taurus Electro G2.5 which features additional improvements and utilizes a selection of technology introduced with the Pipistrel Alpha Electro program.
In 2011 Pipistrel introduced the world’s first four seat electric aircraft. This was a special concept aircraft designed to participate in the NASA challenge series which the Taurus G4 went on to win the largest ever prize awarded in aviation history. This unique design of 2 fuselages joined together with a large central platform was electrically powered and had a range of several hundred miles.
In 2014 Pipistrel saw an opportunity for a completely new training aircraft utilizing electric propulsion. The success of the Pipistrel ALPHA Trainer aircraft made it the ideal aircraft to convert to electric propulsion. The team at Pipistrel worked hard from 2014 until the end of 2017 when the Pipistrel ALPHA Electro was officially released to our customers. It became an immediate success with more than 50 orders on release.
Electric propulsion just wasn’t enough at Pipistrel as they wanted to extend the technology even further and in 2015 they designed and tested the Hypstair project which was completed in 2017. This was the first serial hybrid electric system for general aviation utilizing an electric motor and batteries as well as a supplemental Rotax engine for regeneration and cruise. This hybrid design produced over 200 kW of power and is slated for serial production in the near future.
Hydrogen was still being explored as a power supply for electric propulsion and in 2016 Pipistrel entered a cooperation to produce what is known as the Pipistrel HY4 hydrogen Aircraft. This was a very interesting project using the original airframe which was developed for the NASA challenge series (The Taurus G4) and whilst the airframe was kept predominantly the same the complete power plant section was removed and replaced with electric and hydrogen fuel cells. This was successfully flown in 2017 at the Stuttgart airport in Germany. Progress and modifications are still ongoing to this project.
NASA was an early adopter of Pipistrel Electric Propulsion Systems
Researchers at NASA’s Armstrong Flight Research Center in California were using this unique test stand to understand the intricacies of how electric motor systems and propellers work. Their first choice for testing and benchmark for all other systems was the proven Pipistrel Electric Propulsion System (PEPS) which is shown installed on the test tower below. All of this happened before the first electric NASA X-Planes flew including the X-57.