From instruments to decision support: History, trends and (missed) opportunities

Involvement of the pilot in the closure of the navigation loop has evolved from manual control of the inner-loop, control of the directional loop and outer-loop control . Besides the use of the reference plan to close the navigation loop, the following reasons require a (temporary) deviation: if loss of separation occurs when continuing the plan; and if a collision hazard occurs when continuing the plan . Instruments provide the pilot with the information needed to close the loop and decide when to deviate from the original plan . Besides today´s instruments, various interesting alternatives were designed and implemented. Some of those may be better suited to meet future decision support requirements. This presentation addresses the conceptual similarity between alternatives that have been investigated in the context of closing the navigation loop.