Developer and operator of the solar stratospheric electric aircraft SolarStratos (HB-SXA)

SolarXplorers SA (SolarStratos)

Yverdon-les-Bains · PayerneNew on Amplifa

2014Official project launch

approx. 15Employees (project team)

2Sites (office/test base)

450 kgTake-off mass of the aircraft

24.8 mWingspan

About SolarStratos

SolarXplorers SA operates, under the project name SolarStratos, a two-seat, single-engine electric aircraft with solar equipment developed for stratospheric flights. The low-wing aircraft designed by Calin Gologan was built at Elektra-Solar GmbH in Hurlach (Germany) and is made of carbon fiber composite (CFRP). The upper surfaces of the wing and horizontal stabilizer were covered with 22 m² of solar cells at CSEM in Neuchâtel; the aircraft is powered by a dual electric motor delivering 2×19 kW via a three-bladed variable-pitch propeller, supplied by lithium-ion batteries (20 kWh, approx. 80 kg) from the manufacturer Kreisel Electric. The project team of about 15 people includes aeronautical engineers, pilots and designers; the main address is located in Yverdon-les-Bains, with the flight operations and test base in Payerne. The project aims to demonstrate stratospheric flights powered by solar energy and to commercialize the technologies developed, in particular stratospheric solar drones.

Site: Yverdon-les-Bains
Processes: Stratospheric flights with a solar electric aircraft, Development of stratospheric solar drones (planned), Club/sponsoring program, Warrants SolarXplorers SA, Flight simulator experiences, Workshop/operation of the electric aircraft HB-SXA
Materials: Carbon fiber composite material (CFRP), Lithium-ion batteries, Solar cells, Carbon fiber composite material
Employees: approx. 15 (project
Industries: Aerospace, Renewable Energies, Eco-Exploration / Event & Sponsoring, Eco-Exploration/Event & Sponsoring

01
Design and feasibility study
02
Construction of the aircraft (Elektra-Solar GmbH, Hurlach)
03
Integration of solar cells (CSEM Neuchâtel)
04
Operation and test flights (Payerne)
05
Altitude and record flights
06
Planned commercialization of the technology

Materials & Components

CFK

Carbon fiber composite material

Construction method of the two-seat low-wing aircraft for low weight and high strength.

Li-Ion

Lithium-ion batteries

20-kWh energy storage (approx. 80 kg) from Kreisel Electric for the propulsion.

Solar cells

22 m² of cells with 22–24% efficiency on the wing and horizontal stabilizer, applied by CSEM Neuchâtel.

Sites

Yverdon-les-Bains

Office / main address

Payerne

Flight operations and test base

Aircraft HB-SXA

**SolarStratos HB-SXA**Electric aircraft · Stratospheric research

Inside the production

Industries

AerospaceRenewable EnergiesEco-Exploration / Event & SponsoringEco-Exploration/Event & Sponsoring

Additional services

Stratospheric flights with a solar electric aircraftDevelopment of stratospheric solar drones (planned)Club/sponsoring programWarrants SolarXplorers SAFlight simulator experiencesWorkshop/operation of the electric aircraft HB-SXA

Project History

2012–2013
Team building and initial feasibility study
2014
Official project launch by Raphaël Domjan (17.03.2014); financing via crowdfunding
2014–2015
Finalization of the design and start of construction of the aircraft
2016
Rollout of the prototype on December 7, 2016 in Payerne
2017
First flight on May 5, 2017 in Payerne, registration HB-SXA
2018
Breakage of the left wing during a ground test on July 6, 2018; test flights from 2018
2020
First parachute jump from an electric aircraft on August 25, 2020
2025
Altitude record on August 12, 2025: 9,521 m reached; the project website states 9,640 m according to the FAI announcement (three world records)