We took K2 out today in blustery conditions with winds from the South. We flew the same 50 sqm kite as yesterday, with this morning’s new bridle. The bridle distributed the load in such a way that the kite looked very flat, and we decided both that this bridle was not an improvement and that it was too windy for such a large kite. We then launched the 18 sqm kite with the unusual planform, which we had not yet flown in sufficient wind. The 18 sqm kite performed very well, and we hit a top speed of 33 knots with 3 crew. Attached kite closeups are mostly of this kite. We will try […more]
We have dramatically improved our true wind estimates by using better sensors that we have on hand. To decide which sensors to use in the future, we have graphed the effect of each type of sensor error on the true wind estimate. Using these values, we can predict the level of true wind accuracy that we can expect from candidate sensors. One thing that these plots make obvious is that small errors in apparent wind speed (lower-right plot) lead to very large errors in estimated true wind angle. Thus, it makes sense to keep our current GPS compass (with approximately 1 degree error), but to choose a new wind sensor with a very high windspeed accuracy.
First test with new 50 sqm kite. Unimpressive performance. Will change the bridle and try again tomorrow. Mary Baker, Betsy’s mom, joined us on this test.
Today we tested again with the red K1 rudder. Consensus: red K1 rudder is much inferior to K2 rudder. We also tried several new camera angles from the Protector, including driving under the kite lines for the first time. Jacques Vincent joined us on this test.
A short test today with the red rudder from K1. We also tried some new camera angles from the Protector, including driving directly in front of and directly behind the kiteboat. Jacques Vincent joined us on this test.
Today we took K2 out for a tow test with one of the two K1 rudders (white rudder) that we modified for use on K2. We towed in a straight line while slowly accelerating to 22 knots, then stopping and slowly accelerating again. We attached the tow rope to the chair so we could record load data for this exercise. We then launched the kite near Treasure Island and kited briefly with Michael Specter from the New Yorker, who joined us again. The wind was very low, and we had trouble keeping the kite aloft, but we were able to both launch and sail in about 6 knots of wind. We also saw some more of the Youth America’s Cup […more]
A successful test today, kiting between Treasure Island, Richmond, and Berkeley. Wind was as low as 6 knots near Richmond, but further south we had the same great wind conditions as Monday, with much less traffic on the water, and we hit a top speed of 29 knots heading back toward Berkeley. Jamie joined us on the Protector for real-time data monitoring.
