Solar Impulse's prototype aircraft is en route to Paris Le Bourget from Brussels Zaventum, following an earlier unsuccessful attempt in which the solar-powered aircraft's journey was aborted in mid-flight because of unfavourable weather conditions.
The team behind the project is hoping to land the prototype, registration HB-SIA, at Le Bourget in time to carry out flight displays during the Paris air show, which kicks off on 20 June.
The aircraft originally took off from Brussels at 18:36 local time on 11 June but was forced to turn back just over 3h later. Cloudy weather conditions meant that the aircraft's solar panels were unable to absorb enough energy to charge its batteries sufficiently to continue with the flight.
"Because of the weather, the level of the charge of the batteries went down faster than expected, and we considered that it was safer to turn back," said Solar Impulse chief executive André Borschberg, adding: "It is an experimental project and we therefore make attempts that aren't necessarily always successful."
To prevent this from happening again, the batteries were fully charged on the ground, partly using electricity, ahead of the latest attempt. Weather conditions allowed for 60% of the charge on the ground to come from sunlight, but the remaining 40% was provided by electrical power.
Solar Impulse's latest attempt took off from Brussels Zaventum Runway 25R at 05:20 on 14 June and is scheduled to land at Le Bourget at about 21:00 the same day. The prototype will fly at an average altitude of 8,200ft (2,500m). Its route will take it via Valenciennes and Reims.
The flight will be "difficult to execute" because it will take place between two weather fronts, said Solar Impulse.
If the prototype manages to successfully land at Le Bourget, it will take part in flying displays each morning during the Paris air show, weather permitting.