Agricultural aircraft control system using the global positioning system

An aircraft control system for use in an agricultural aircraft for applying chemicals to an agricultural field in one of a plurality of flight patterns, said aircraft having at least one dispenser valve for releasing said chemicals from a reservoir, said aircraft control system comprising:

• global positioning receiver means for receiving said radio frequency signals from a plurality of global positioning satellites and for generating position signals representative of said radio frequency signals;
• computer means, responsive to said global positioning receiver means, for storing surface coordinates of the boundary of said agricultural field, for selecting said one of said plurality of flight patterns of said aircraft, for orienting said one of said plurality of flight patterns in response to said orientation signal, and for decoding said position signals to determine continuously the position of said aircraft, said computer means including means for automatically activating said at least one dispenser valve when said aircraft is flying within the boundary of said agricultural field whereby said chemicals are applied to said agricultural field;
• and
• pilot interface means, responsive to said computer means, for indicating deviations of said aircraft from said one of said plurality of flight patterns to a pilot of said aircraft and for providing an orientation signal representative of desired flight path orientation of said one of said plurality of flight patterns in response to said pilot selection such that said pilot guides said aircraft along said one of said plurality of flight patterns to apply said chemicals to said agricultural field.

A method for controlling application of chemicals to an agricultural field using an agricultural aircraft, said aircraft having at least one dispenser valve for containing and releasing said chemicals, said method comprising the steps of:

• providing surface coordinates of the boundary of said agricultural field;
• selecting one of a plurality of flight patterns;
• receiving radio frequency signals from a plurality of satellites;
• decoding said radio frequency signals to determine continuously the position of said aircraft relative to said agricultural field and said one of said plurality of flight patterns;
• indicating to a pilot of said aircraft deviations in position of said aircraft from said one of said plurality of flight patterns;
• and
• automatically activating said at least one dispenser valve when said aircraft is flying within the boundary of said agricultural field whereby said chemicals are applied to said agricultural field.