Solar Impulse set for early hours take-off on final leg to Abu Dhabi

Solar Impulse 2 lands in Cairo on July 13. Mission control hopes it can take off on its final, 48-hour leg to Abu Dhabi in the early hours of Sunday morning. AFP

ABU DHABI // Anticipation is building over whether Solar Impulse 2 will finally take off from Egypt to Abu Dhabi in the final leg of its historic round-the-world fuel-free flight.

The sun-powered plane has been grounded in Cairo since it landed there on July 13. It was due to take off last week but the flight was suspended last minute due to poor weather and pilot illness.

But as co-pilot Bertrand Piccard appears to have bounced back to health and favourable weather conditions are on the horizon, Solar Impulse is tentatively scheduled to depart for its final flight at 3am on Sunday UAE time.

"The MCC [Mission Control Centre] team has identified a weather window that could allow us to overcome the challenging high temperatures across Saudi Arabia and hopefully land in Abu Dhabi after 48 hours," the crew wrote on solarimpulse.com.

“For this, however, we need to be able to take off from Cairo! Conditions are tricky with winds challenging Si2’s limitations on the runway. We are therefore getting ready for an attempt but there is a risk that we will need to postpone the flight at the last minute.”

Solar Impulse, which began its journey in Abu Dhabi in March last year, has flown to 16 destinations around the world.

“After experiencing the most humanly challenging flight last year with André’s [Borschberg, the other co-pilot] five day and night flight, this leg will definitely be the most technically challenging on this round-the-world mission,” the MCC wrote. “Our provisional take-off from Cairo, Egypt, to Abu Dhabi, UAE, will be at 11.00PM UTC on July 23 and 1:00AM CEST, 7:00PM EDT on July 24. We are likely to have to adapt timings - so, as always with Solar Impulse, stay on your toes.”

A live stream of the flight, along with daily programming, can be viewed at solarimpulse.com.