Verstraeten became known for his efforts to try to be the first to circumnavigate the world non-stop with the Rozière balloons Breitling Orbiter 1 (1997) and Breitling Orbiter 2 (1998) together with his co-pilot the Swiss Bertrand Piccard.
In 1985 he was the first Belgian to cross the Channel in a balloon.
In 1990, he was the first to fly a balloon over the Kilimanjaro and in 1992 he was the only one to fly across the Atlantic in a five-balloon competition.