On March 26 in a dry lakebed in California, the craft broke the world land-speed record for wind-powered vehicles by more than 10 miles an hour, setting the new record at 126.2 mph.
Greenbird uses a solid, vertical sail—shaped like an aircraft wing—to capture the wind. The craft's unique low-drag design, coupled with the power of "apparent wind" (a combination of true wind and the wind force created by forward motion), allows it to travel at up to five times the true wind speed.
in the caption of the second picture it reads "... with an equally tail sail..."
I'm not sure what that means. I'm not trying to knit-pick a potential typo I'm just interested in getting all the information I can from this article.