An aircraft formation/refueling guidance system guides a follower aircraft relative
to a leader aircraft. A datalink provides a position hold and a bias command from
the leader aircraft to the follower aircraft. An optical tracker onboard the follower
aircraft takes an image of the leader aircraft when receiving the hold command,
tracks the leader aircraft using the image, and provides optical tracker movement
outputs. A resolver resolves the optical tracker movement outputs to provide resolver
control signals. A vernier control receives the bias command to change a position
of the follower aircraft by biasing the resolver control signals with a bias signal.
A sum circuit connected to the resolver and to the vernier control receives the
resolver control signals and the bias signal to provide a sum circuit output signal.
An autopilot and autothrottle receives the sum circuit output signal and the position
hold command to control the follower aircraft.
