Studies on water movements and sediments in Southern Lake Michigan : part 1[-3] ... / by John C. Ayers.

outside diameter. This pipe (staff) extended 6-1/2 feet
above the top of the styrafoam and three feet below it. The
lower end of the aluminum staff was weighted with three onepound iron fish-net sinkers, and four guy-wires ran from the
bottom of the staff through the corners of the styrafoam to
15 inches from the top of the staff. At the top of the staff
was mounted a wire-mesh radar corner reflector measuring one
foot in each dimension.
In the usual use these floats exposed to the wind the
radar reflector, the upper portion of the staff, the guy wires,
a rope bridle for recovery, and one side of the styrafoam
float (16-1/2 x 4 inches exposed)0 Total area exposed to the
effects of wind was 270 square inches.
Figure 5 presents the details of this test. Drogues III
and IV were normal surface drogues; each carried at the lower
end of its staff a 4-foot x 8-foot sheet of galvanized iron
rolled and bolted into an open-ended cylinder and suspended
by a light chain bridle. These drogues were influenced by the
upper 7-1/2 feet of water. Drogue II carried two current drags
(cylinders) in tandem and was effected by the upper 12 feet of
water. The tandem drag configuration was used on the assumption that windage on the float would not be able to tow it to
any significant degree.
As shown in Figure 5, drogues II, III, and IV retained
about the same relative positions to each other from the "noon"
fixes of the 9th until recovery on the morning of the 10th.
Drogue II travelled 6.7 miles during its total period
adrift; this gives an apparent mean speed of 0.29 mph. Drogues

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