TM 5-3740-218-13&P
G-4.
ACRE/SWATH CHART
Two pieces of information are supplied by this chart:
a. Acres per Swath Run. Acres are determined by swath width and length of swath run. Lengths of swath run are
given in fractions of a mile, tenths of a mile, and increments of 100 feet up to 1 mile starting at 600 feet.
b. Seconds per Swath Run. This information is a conversion of miles per hour to seconds per given distance. It
has no relation to how wide the swath is. This information is reprinted exactly on the Acre/Swath Chart only as a
convenience to the user.
G-5.
USES FOR ACRE/SWATH CHARTS
a. By using a stopwatch, you can determine the field length by flying a constant air speed. If the width is also
measured, field acreage can easily be obtained: L x W x 43560 = Acres.
b. By knowing the field length, you can obtain the acres per swath width.
c.
By dividing the acre load in the hopper by the acres per swath run, the number of passes can be obtained.
NOTE
For convenience, the column that gives air speed most used can be shaded in with a
marking pen. This will save time searching for the correct column.
The rounding off of numbers was purposely left up to the user. This will give the user an idea of how much error is being
put into the answers. Rounding off will make these charts more convenient and should not be discouraged.
G-6.
AIR APPLICATION FORMULAS
a. Acre/Swath Run
= Field Length x Swath Width
43560
b. Acre/Swath Run
= MPH x SW x Seconds Traveled x 0.0000337
or
= MPH x SW x Seconds Traveled x 1.466
43560
c.
Acre/Min
= MPH x SW x 0.0020202
G-4
