The Swiss sun-powered aircraft Solar Impulse is waiting for weather conditions to improve before continuing on its first transcontinental flight, organisers said Wednesday.
The experimental plane, which is not designed to fly into clouds, landed in Madrid on Friday from its home base in Payerne in Switzerland at the end of the first leg of its attempt to reach Morocco without using a drop of fuel.
After technical checks and a pilot change it was hoped Solar Impulse would leave for Rabat on Monday but its departure was put off due to strong winds.
"At present, we are waiting for a good weather forecast window on the Madrid-Rabat leg. For sure we know that it won't be until Monday," project spokeswoman Charlotte Pichon told AFP.
If successful the 2,500-kilometre (1,550-mile) journey will be the longest to date for the aircraft after a flight to Paris and Brussels last year and it will mark the first time that the plane has left Europe.
The trip is intended as a rehearsal in the run-up to the plane's round-the-world flight planned for 2014.
The high-tech aircraft, which has the wingspan of a large airliner but weighs no more than a saloon car, is fitted with 12,000 solar cells feeding four electric motors driving propellors.
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