Solar energy pioneer Raphaël Domjan and his team continued preparations for the altitude record attempt at 10,000 metres with the SolarStratos solar aircraft. +Get the most important news from Switzerland in your inbox From Sion in Valais, HB-SXA climbed to an altitude of more than 4,000 metres on Friday. Domjan flew past the Matterhorn, among other places. The aircraft is to be prepared to fly to an altitude of 10,000 metres. This would be a record for manned electric solar aeroplanes. SolarStratos was previously stationed in Payerne. Domjan and his team have taken up residence at Sion airport for the summer. There, the experts are waiting for the "first favourable weather window" to take advantage of the summer thermals and fly the aircraft to the targeted altitude. + Five unusual places to install solar panels in Switzerland Domjan made his first attempt last summer, but it ended at 5,963 metres. This meant that he was unable to beat Bertrand Piccard's Solar Impulse altitude ...