SCPA & SBSA Discussion Board

Nasty Wind Event appears eminent, but Bates will likely offer a window this morning in transition to blowing out.

Bates to Pitas
http://paraglide.net/log/10/10_04-28/1_ ... _pitas.htm

Were you wearing a "wet" suit?

Tom, how did you carry that 20 lbs of water ballast exactly? The first and only time, so far, that I flew Chief's Peak, I was flying the Windtech Kinetik wing and was carrying a gallon of water in the back pocket (at the very bottum) of my harness. This was when I was low in air time still, but I had a hard time doing staying above the ridge just behind Sisters or Twins (whatever that peak is just below and to the right of launch) while trying to do efficient 360 degree turns. Robb Milley and the others who hosted that intro day to Ojai can attest to how I flew, which took place a month less than 2 years ago from now.

Since then, I try to carry my ballast closer to my center of gravity. My harness does not have any pockets for ballast besides the big pocket behind my seat cushion, and that is as far from me as possible. I tend to think this makes the weight of my harness counter act the weight shift inputs I put on my wing. Nowadays I have a 10 lbs weight vest that I wear occasionally when I fly, that is not the most comfortable thing, though makes my wing more responsive.

Simon wrote: I try to carry my ballast closer to my center of gravity.

Simon, are correct that carrying ballast low tends to dampen the weight shift authority and make the glider harder to turn. Break pressure is proportional to loading, so even with the ballast loaded high, the breaks will still feel heavy.

15 years ago, all the comp pilots flew large gliders and carried a lot of ballast because there is an efficiency of scale. L/D improves with size for the same loading (pounds per sq foot) because the parasitic drag is a large component of total drag in a PG and it doesn't scale linear with the size. Big guys will glide better then light girls in calm air. It's a sexist sport.

Optimally, you want to be able to dump the ballast in flight, and some harnesses are set up to do so, but not mine. I was carrying the ballast high in my back storage the other day, but it didn't work well. I carry it in the same place on my tandem harness and that works ok. I have two 10Kg bladders, specifically marketed as ballast bags, but you can also use them as general water bags when camping. They come with a shower hose kit. I sometimes fly with both bags when I have a light tandem passenger. If so, I have to put the 2nd bag on the passenger, which I don't like to do because it makes it hard for them to run. In addition to occasional extra ballast, I normally fly with 2 liters of water, and sometimes 3 in the summer.

I think most pilots have gotten away from using ballast for a number of reasons. It makes ground handling awkward and there are issues on a hard impact. I've gained 20 pounds over the past 5 years, so I've got build in ballast now.

You can also check my notes on wing loading from 2002 at
http://paraglide.net/comment/02/wing_loading.htm