Posted by Maciek on January 27, 2002 at 00:34:57:
In Reply to: Backplates and trim posted by seahunt on January 26, 2002 at 21:06:42:
I don't know about you, but I for 95% of my dive stay horizontal. When I swim forward I swim horizontal. If my trim forces me to go feet down:
1) When I stop I will go vertical and air in my BC will expand a little becuase it's going to be moved above my center of gravity which supposedly will stay at same level. That means that if you were neutral, you no longer are.
2) When something really interesting happens on a bottom I can't just stop with my face inches from it. I mean STOP. Don't move. I have to constantly fight for horizontal position by paddling.
3) If my feet are heavier my body never really is horizontal. So I swim forward and frontal area I push through the water is bigger than if I were horizontal. As it was stated zillions of times resistance is actually proportional to that area cubed. That mean small change makes a big difference.
How do I know it works?
Well... I got 20% better air consumption up front when I switched to a backplate. (Yes I actually measured it). And I was far from being streamlined, cos I dove with paraschute size Explorer 45lbs wing. It was just a trim.
Maciek