1. A computer-implemented method of generating a description of aircraft intent expressed in a formal language that provides an unambiguous description of an aircraft's intended motion and configuration during a period of flight, comprising: obtaining a description of flight intent corresponding to a flight plan spanning the period of flight; ensuring that the flight intent description is parsed to provide instances of flight intent, each instance of flight intent spanning a flight segment with a plurality of flight segments together spanning the period of flight, wherein the plurality of flight segments represent an intent of changing an aircraft motion state from one state into another; for each flight segment, following a set of attributes comprising an effect, an execution interval, and a flight segment code that govern a creation of valid words, wherein the effect comprises aircraft behavior exhibited during the flight segment represented by a composite, the execution interval defines an interval during which the flight segment is active defining an initial aircraft state and a final aircraft state, and the flight segment code comprises an alphanumeric string indicating degrees of freedom of motion of the aircraft that are not closed by the composite; for each flight segment, generating an associated flight segment description that comprises at least one or more instances of flight intent, wherein each instance of the at least one or more instances of flight intent provides a description of the aircraft's motion in at least one degree of freedom of motion thereby closing the at least one degree of freedom of motion and/or provides a description of the aircraft's configuration to close at least one degree of freedom of configuration; identifying the plurality of flight segments where not all degrees of freedom are closed and completing the identified flight segments by adding one or more instances of flight intent to close all degrees of freedom; and collating flight segment descriptions thereby providing the description of aircraft intent for the period of flight expressed in the formal language to assist in flying the aircraft with the unambiguous description of the aircraft's intended motion and configuration during the period of flight.