The Aircraft Intent Description Language: A key enabler for air-ground synchronization in Trajectory-Based Operations

Abstract

In this paper, a formal language called the Aircraft Intent Description Language (AIDL) is proposed as a standard, interoperable means of describing and exchanging predicted aircraft trajectories in Trajectory-Based Operations (TBO). The AIDL provides the necessary elements to unambiguously formulate aircraft intent, which, in the context of trajectory prediction, refers to the information that describes how the aircraft is to be operated within a certain time interval. By expressing aircraft intent according to the AIDL, it is ensured that each instance of aircraft intent defines a unique trajectory. It is anticipated that sharing aircraft intent information expressed in a structured and formal manner, e.g. according to the AIDL, can facilitate the synchronization of the predicted aircraft trajectories held by different automation systems in the context of TBO.

Applications of Formal Languages to Management of Manned and Unmanned Aircraft

“…This process is described in detail in [15,16], although a summary of the process is included here for completion.…”

“…This led to the development by BR&TE of the aircraft intent description language (AIDL) [15,16], a formal language derived from the generic mathematical formulation of the trajectory computation process. This makes the AIDL a rigorous and generic means of describing aircraft intent.…”

“…One formal language has already been developed for describing fixed-wing aircraft trajectories [15,16], the aircraft intent description language (AIDL). Since this language can only be used to describe trajectories of that type of aircraft, it will be often denoted fixed-wing AIDL (FW-AIDL) in this thesis.…”

“…However, it also makes the resulting definition of the AIDL highly dependant on the aircraft motion model (AMM), that is, the set of equations describing the aircraft motion. The AIDL developed in [15,16,47] was designed to describe trajectories of commercial fixed-wing aircraft, and therefore it cannot be used for describing trajectories of other types of aircraft, such as vertical take-off and landing (VTOL) fixedwing aircraft, helicopters, or multirotors. For clarity, the AIDL derived from the equations of motion of a commercial fixed-wing aircraft will be hereafter referred to as the fixed-wing AIDL (FW-AIDL).…”

“…The AIDL [15,16,47,48] is a formal language developed by BR&TE to describe aircraft intent information. This language was designed to be generic, so it can describe any aircraft behaviour that is meaningful in ATM, and rigorous, so that a behaviour described in this language is consistent and unambiguous.…”