Product Pick of the Week - A windpowered car that can travel faster than the wind

Led by Rick Cavallaro, DDWFTTW has developed a wind-powered car called the Blackbird that is capable of traveling upwind at speeds faster than the wind! In 2010 Cavallaro’s team set a world record by traveling downwind at 2.8 times the speed of the wind – and they recently tweaked the vehicle to travel upwind as well. The downwind record was an amazing accomplishment, but the latest feat is even more astonishing.

Earlier this month Rick Cavallaro and the Blackbird team took their modified wind-powered car to the New Jerusalem airport in Tracy, California to attempt to set a new record. This time the team traveled 2.01 times faster than the wind speed when headed upwind.

“For some folks, the idea that it can advance directly into the wind at all has been counter-intuitive,” said Cavallaro. While it may seem like a wind-powered vehicle heading directly into the wind could end up traveling faster and faster in an endless feedback loop, that isn’t the case. “There’s at least an element of truth to this, but as with the downwind cart, frictional losses still win out at a certain speed,” Cavallaro said.

For the latest test, the team made only minimal changes to the Blackbird. The biggest changes were the replacement of the propeller with a turbine and the removal of the transmission. The turbine looks similar to the original propeller, but it spins in the opposite direction and sends its power to the wheels.

Now that the team has most likely set a new record with its latest upwind run, Cavallaro hopes that other teams will develop new system that will break both of his team’s records.

About the Blackbird:
In 2009 we set out to conclusively answer the following question... Can a vehicle be built which can go directly downwind, faster than the wind (DDWFTTW), powered only by the wind, steady state? On 3 July 2010 we established a world record by going directly downwind at 2.8 times the true wind speed with the Blackbird. Now we have begun to modify the Blackbird with the intention of going directly UP-wind faster than the wind - steady state.

The blades are "done" and fiberglassed. They still need to be painted and sanded, but I decided to go ahead and extend the spars for mounting in our existing hub. Had I been a little smarter, I would have left them sticking out a bit further to begin with, but the extensions will really beef up the roots - so I don't mind.

Next I'll add the fiberglass sleeves over the spar roots so they slide perfectly into the hub and bearing races. After that we'll have to increase the gear size on the rear axle fairly substantially for the upwind runs. Then I'll add a chain guide up top to keep the chain from coming off the upper chain wheel (since it will now be running in the other direction), some minor trailer repair, and then head out to the runway at New Jerusalem on a windy day.

We're still shooting to do some unofficial runs in the next few weeks.

About Us:
Thin Air Designs is a research group focused on disruptive high reward technologies. Our projects hold a strange counter-intuitive promise. Our Direct Downwind Faster Than The Wind (DDWFTTW) demonstration project (Blackbird) has people scratching their head and talking.