Swiss adventurer Bertrand Piccard’s team took its round-the-world solar plane prototype into the skies for the first time Wednesday, with four propellers lifting the massive craft off the ground at near bicycle speed.

Piccard said the two-hour test flight will examine if the plane, with the wingspan of a Boeing 747 and the weight of a small car, can keep a straight trajectory. The team plans to fly it around the world next year.