Publications
Collision avoidance for general aviation
Summary
Summary
The Traffic Alert and Collision Avoidance System (TCAS) is mandated on all large transport aircraft to reduce mid-air collision risk. Since its introduction, no mid-air collisions between TCAS-equipped aircraft have occurred in the United States. However, General Aviation (GA) aircraft are generally not equipped with TCAS and experience collisions several...
The Tower Flight Data Manager prototype system
Summary
Summary
The Tower Flight Data Manager (TFDM) will serve as the next generation air traffic control tower automation platform for surface and local airspace operations. TFDM provides three primary enhancements over current systems: consolidation of diverse data and information sources into a single platform; electronic data exchange, including flight data entries...
Analysis of open-loop and closed-loop planning for aircraft collision avoidance
Summary
Summary
Open-loop planning has been a popular approach for developing aircraft collision avoidance systems. Open-loop planning computes a future plan to follow without anticipation of how future observations can affect the future course of action. Closed-loop planning, in contrast, takes into account the ability to react to future information. This paper...
Establishing a risk-based separation standard for unmanned aircraft self separation
Summary
Summary
Unmanned Aircraft Systems require an ability to sense and avoid other air traffic to gain access to civil airspace and meet requirements in civil aviation regulations. One sense and avoid function is self separation, which requires that aircraft remain well clear. An approach is proposed in this paper to treat...
A field demonstration of the air traffic control Tower Flight Data Manager prototype
Summary
Summary
The development and evaluation process of the Tower Flight Data Manager prototype at Dallas Ft. Worth airport is described. Key results from the first field evaluation are presented, including lessons learned about making electronic flight information acceptable to controllers. Iteration of the field evaluation methods are discussed for practitioner benefit.
Hazard alerting based on probabilistic models
Summary
Summary
Hazard alerting systems alert operators to potential future undesirable events so that action may be taken to mitigate risk. One way to develop a hazard alerting system based on probabilistic models is by using a threshold-based approach, where the probability of the undesirable event without mitigation is compared against a...
Accounting for state uncertainty in collision avoidance
Summary
Summary
An important consideration in the development of aircraft collision avoidance systems is how to account for state uncertainty due to sensor limitations and noise. However, many collision avoidance systems simply use point estimates of the state instead of leveraging the full posterior state distribution. Recently, there has been work on...
Collision avoidance system optimization with probabilistic pilot response models
Summary
Summary
All large transport aircraft are required to be equipped with a collision avoidance system that instructs pilots how to maneuver to avoid collision with other aircraft. Uncertainty in the compliance of pilots to advisories makes designing collision avoidance logic challenging. Prior work has investigated formulating the problem as a Markov...
Unmanned aircraft collision avoidance using continuous-state POMDPs
Summary
Summary
An effective collision avoidance system for unmanned aircraft will enable them to fly in civil airspace and greatly expand their applications. One promising approach is to model aircraft collision avoidance as a partially observable Markov decision process (POMDP) and automatically generate the threat resolution logic for the collision avoidance system...
A new approach for designing safer collision avoidance systems
Summary
Summary
The Traffic Alert and Collision Avoidance System (TCAS) has been shown to significantly reduce the risk of mid-air collision and is currently mandated worldwide on all large transport aircraft. Engineering the collision avoidance logic was a very costly undertaking that spanned several decades. The development followed an iterative process where...