D1: unmodified TCAS symbology
D2: circle around aircraft indicates protected volumes, red circle represents predicted collision area, time to loss of separation (LOS) is also indicated in seconds
D3: TIME to LOS is used as radar scale instead of separation distance, LOS time shown, and ground speed velocity indicators for each aircraft
TCAS DISPLAY FOR MICROSOFT FLIGHT SIMULATOR 2002
Ecological Interface Design in Aviation DomainsImproving Pilot Trust in Automated Collision Detection and Avoidance
Catherine M. Burns
Advanced Interface Design Laboratory
Systems Design Engineering
University of Waterloo
APPLYING EID TO COLLISION DETECTION & AVOIDANCE
- This study introduces a novel approach to applying EID to collision detection and avoidance, dividing the problem into 3 entities
- (A)ircraft, (T)CAS, and (E)nvironment
- A: One AH representing flight dynamics for each aircraft involved in the encounter
- T: One AH of the TCAS system for each aircraft
- E: One AH describes the airspace of the collision encounter
ECOLOGICAL INTERFACE DESIGN
- Ecological Interface Design (EID)
- A domain-independent framework for designing interfaces primarily for complex systems (Vicente, Rasmussen, 1992)
- Nuclear power plant control (Rasmussen, 1985)
- Aircraft engineering system (Dinadis & Vicente, 1999)
- Shipboard command and control (Burns et al., 2000)
- Shown to improve operator task performance and problem identification because it establishes a contextual link between system data to the trained operator
- EID: “What data should be extracted, and how should it be presented to help the user understand the system?”
- EID uses Work Domain Analysis (WDA) (Rasmussen 1985) as the design basis
- The pilot did not have the necessary information to perform effectively in the automated alerting situation
- The pilot didn’t know who to trust
- Onboard collision system or air-traffic control?
- To propose display enhancements and evaluate their effects on pilot trust and decision making performance in automated air traffic alerting systems
- The EID methodology should create a display that convinces pilots to perform a task rather than command them to perform a task
On July 1, 2002:
Bakshirian Airlines Tupolov154 collided with a DHL Cargo Boeing 757-200 over Southern Germany
Sequence of events as the two aircraft converged:
1)Onboard collision system told Boeing to climb
2)Onboard collision system told Tupolov to descend
3)Air traffic control (ATC) told Tupolov to climb
6) Collision occurred at 35,000 feet. There were no survivors.
The systemFAILED! How?
WORK DOMAIN ANALYSIS
- The Abstraction Hierarchy (AH)
- A five layer hierarchical model that represents system components and their interaction, vertical interpretation is a means-end (how-why) relationship
ENHANCING THE COLLISION DISPLAY WITH EID
- Traffic Alerts and Collision Avoidance System
TCAS 2 – version 7.0
- Internationally adopted and mandated by FAA for all North American aircraft with capacity exceeding 30
- Operates independently of onboard systems/radar
- TCAS 2 calculates avoidance maneuver
- 2 Levels of Alerts
- TA : Traffic Advisory - ‘traffic, traffic’
- RA : Resolution Advisories - ‘climb’, ‘descend’, etc.
- Algorithm Data Inputs
- intruder range, altitude, bearing
- ownship range, altitude, bearing
- Operating Parameters
- aircraft protected volume varies with speed
- threat based on time (tau), not distance
EXTENDING EID TO IMPROVE
AIR TRAFFIC COLLISION SYSTEMS
- The EID framework is very flexible in its application
- In this study, EID highlights aircraft flight dynamics and the threat environment in which a collision occurs, all of which interact with components of the automated warning system.
- Although the system of focus is TCAS, the flexibility of EID and WDA allows this model to be adapted to any automated collision warning system being developed for aviation. The TCAS entity can be replaced with ADS-B and other systems to produce new system interactions and information requirements for exploring EID-enhancements
- Experimental results will indicate if EID-enhanced displays improve pilot reaction time and conformance to TCAS alerts
- Results comparison between time-scaled and distance-scaled displays will provide additional information on their effects on pilot collision detection performance
- Burns, C.M., Bryant, D.J., & Chalmers, B.A. (2000). A work domain model to support shipboard command and control. Proceedings of IEEE Transactions on Systems, Man and Cybernetics. 2228 – 2233.
- Dinadis N., & Vicente, K.J. (1999). Designing functional visualizations for aircraft systems status displays. International Journal of Aviation Psychology. Vol. 9 (3), 241-269.
- FAA (2000). Introduction to TCAS II Version 7. U.S. Dept. of Transport. Federal Aviation Administration. Nov. 2000.
- Rasmussen, J. (1985). The role of hierarchical knowledge representation in decision-making and system management. IEEE Transactions on Systems, Man and Cybernetics, 15(2), 234-243.
- Vicente, K.J. & Rasmussen, J. (1992). Ecological interface design: Theoretical foundations. IEEE Transactions on Systems, Man and Cybernetics, 22(4): 589-606
- Centre for Research in Earth & Space Technology
- Sion Jennings, NRC Flight Research Lab