You should do some fact checking on your info Rob,
Mostly though, they are safe. All the lines lead to the deck, so there is no heeling or nosediving. Biggest worry is getting airborne, more a problem on a beach cat than a large cat.
More people have gotten killed by going airborn under a kite than by flying an assymetric spinnaker. As a result power kiting and buggy kiting are banned on the Dutch beaches and waters now. They may only sail at certain reserved spots and after acquiring a license. For buggy's you'll now need an official (landyacht) pilot license and you must do an exame for that.
420 sqm kite on a 20m/66' skiff
20-25 sq.mtr is enough to fly 75-90 kg human beings (paragliders) so 420 sq. mtr. is enough to fly 1500 kg. How much did that 20 mtr skiff weight ? So what do you mean exactly by "more a problem on a beach cat than a large cat."
Conventional assy's have an aspect ratio of about 2:1
Maybe on mono's but not on beach cats
F18 => (8.25)^2/21 = 3.24 aspect ratio
Tornado => (8.75)^2/24 = 3.19 aspect ratio
F18HT => 9^2/20 = 4.05 aspect ratio
None have been used on beach cats yet,
- 70's and 80's experiments
http://www.cobrakite.com/jaclad.html- 80's world record set by Tornado platform with a kite
"Kite boats are already allowed in speed sailing. A world record was set and held for 7 years by a kite powered Tornado, back in the early 1980's"
Source :
http://www.sailinganarchy.com/innerview/2003/daveculp.htm
They are 20-50% more effective than a spinnaker due to flying higher in clearer, stronger air and not being affected by other sails or the boats motion
Issues with kites :
- Try sailing under bridges or power lines
- Try bouy racing with them
- Try to stay in the water with them (not get fully airborn)
- Try sailing upwind with them
- The sagging of the lines transmitting the force is a serious problem in upwind sailing or high speed sailing.
With respect to efficiency of kites. Yes they are theoretically and practically more powerful than assies, however they (used to) have rather bad lift to drag ratios and are (were ?) far less attractive upwind dan normal sails. This ratio and the sagging of lines also impeded very high speeds. Landspeed records and water records (boats and surfboards) are once again set using conventional masted sails.
Kites are quite interesting but they are far less new or promising than some make them out to be.
Wouter
(Yes I did a stint at kite flying and building as well, several years back I must admit)
