TFOX,

I'm afraid that I can't agree with you. Air and water are both types of fluids. If a fluid moves at a certain rate with an item embodied in that fluid, the object will move at the same rate as the fluid. There maybe factors that effect the amount of drift in a given time period like the speed of the item, or the angle of the crosswind or water current to the intended course path. These factors would influence the amount of possible weathervaning in the fluid. Since there is a certain amount of drag on an object given enough time it will weathervane itself into the current. With an arrow it eventually float in the media with the tip into the current because the greatest amount of drag is on the fletched end. However, the air mass or water mass still moves a certain amount distance in a period of time and will take the object in its flow path. It gets even more complicated when you deal with both water and wind at the same time because of the amount of water displacement that an object has and the size of the freeboard above the waterline for the wind to effect the drift which maybe from another direction. In this case you would end up with an effective composite drift vector from both the effects of the wind and water currents.

A larger arrow will tend to weathervane faster because it has more drag than the smaller sized arrow, but the amount of drift remains the same. This sometimes is misinterputed as more drift, the lateral movement is the same. To understand this more you might want to look at headwinds and tailwinds on an object. If an aircraft has a 40 mph tailwind and it is flying at 200mph of airspeed, it would have traveled 240 miles over the ground in a hour, or the composite sum of the airspeed and the wind. If the aircraft is flying in same speed headwind the aircraft would have traveled 160 miles over the ground and the airspeed would still be 200. In the case of a crosswind the air mass moves the object off course at the speed that the air mass moves in an hour at 90 degrees to the path. If the angle of flight to the wind is less than 90 degrees the drift will vary with the angle of the crosswind component.

Edited by - FLHunter on 01/08/2002 08:58:11