Some falconry delta kites have a helium bladder in the Keel to keep it stable in very light winds, although a good delta should be fine in 2mph.
I was approached by a falconer at a fly-in for the biggest lifting kite I had. No lifters were available, so we came up with a 2m rokakku, this used 12mm carbon spars. Flew on 325lb line and a 1m piece of rebar driven into the ground as an anchor, you didn't hand fly this kite.
The falcon lure was Hung 3m below the line, about 10m below the kite, the optimum place for hanging beer cans for lifting demonstrations.
The falcon flew around for a couple of minutes until the handler whistled. It swooped down to the lure and dragged the kite to the ground quicker than I could run it down with a pulley.
Very impressive.
Last edited by morticiaskeeper; 14th Feb 2012 at 19:12.
Reason: Smartphone spelling :-(