This page contains Information and links to information about attempts to sail a wind-powered craft directly down wind at the highest speed possible. If, as has occurred, that speed exceeds the wind speed, there will undoubtedly be a controversy since many people believe that both common sense and basic physics* say that going faster than the wind in the direction of the wind is impossible.
NALSA's interactive Yahoo Group webpage might be a good place to have a discussion about this. Please keep it civil and meaningful. If there is a flaw in the rules or some indication that the rules have not been followed, obviously changes will need to be made.
Please note: This is not a joke (except my comment about slide rules) or an intentional hoax; everyone involved is taking this seriously. The Blackbird is not claiming to be a perpetual motion machine, it is using energy from the wind; if the wind stops so does Blackbird. They just seem to have figured out a way to turn the wind's energy into forward motion in a way that is more efficient than a parachute, tumbleweed or conventional sail. As far as NALSA can tell the Thin Air folks aren't "cheating."
NALSA DDW ( Directly Down Wind ) Speed record regulations (PDF)
July 2, 2010.
Set by Blackbird, an unconventional sailing craft designed and operated by Rick Cavallaro and John Borton of Thin Air Designs. The Blackbird, piloted by Rick Cavallaro sailed "directly downwind" at 27.7 mph in a sustained 10 mph wind, setting a record for ratio of "boat" speed to true wind speed of nearly 2.8.
*It is possible that the author of this page underestimates the "common" understanding of sailing, and aerodynamics. People experienced with landsailers and iceboats have reported continuing acceleration for at least a short time after turning downwind at high speed which makes it difficult to proclaim "impossible!" in relation to the record published here. See the "faster than the wind" link below for an explanation of the physics involved.
NALSA Submission Report (PDF)
Observer's Report (PDF)
Observer's report Appendix 1 (XLS)
*Faster than the wind (Wikipedia)
Thin Air Designs Website