Estimated time of arrival explained

The estimated time of arrival (ETA) is the time when a ship, vehicle, aircraft, cargo, person, or emergency service is expected to arrive at a certain place.^{[1] [2] [3]}

Overview

One of the more common uses of the phrase is in public transportation where the movements of trains, buses, airplanes and the like can be used to generate estimated times of arrival depending on either a static timetable or through measurements on traffic intensity. In this respect, the phrase or its abbreviation is often paired with its complement, estimated time of departure (ETD), to indicate the expected start time of a particular journey. This information is often conveyed to a passenger information system as part of the core functionality of intelligent transportation systems.

For example, a certain flight may have a calculated ETA based on the speed by which it has covered the distance traveled so far. The remaining distance is divided by the speed previously measured to roughly estimate the arrival time. This particular method does not take into account any unexpected events (such as new wind directions) which may occur on the way to the flight's destination.

ETA is also used metaphorically in situations where nothing actually moves physically, as in describing the time estimated for a certain task to complete (e.g. work undertaken by an individual; a computation undertaken by a computer program; or a process undertaken by an organization). The associated term is "estimated time of accomplishment", which may be a backronym.

Applications

Accurate and timely estimations of times of arrival are important in several application areas:

• In air traffic control arrival sequencing and scheduling, where scheduling aircraft arrival according to the first-come-first-served order of ETA at the runway minimizes delays.^{[4] [5]}
• In airport gate assignment methods, to optimize gate utilization.^[6]
• In elevator control, to minimize the average waiting time or journey time of passengers^{[7] [8]} (destination dispatch).

Notes and References

1. Book: Wragg, David W. . A Dictionary of Aviation . 9780850451634 . first . Osprey . 1973 . 121.
2. Book: Cameron, M. . Brown, A. . Intelligent transportation system Mayday becomes a reality . Aerospace and Electronics (NAECON 1995) . May 1995 . 1 . 340–347 . IEEE.
3. Propp, Douglas A. . Rosenberg, Craig A. . A comparison of prehospital expected time of arrival and actual time of arrival to an emergency department . . July 1991 . 9 . 4 . 301–303 . 10.1016/0735-6757(91)90045-L. 2053997 .
4. Fast-time study of airline-influenced arrival sequencing and scheduling . Carr, Gregory C. . Erzberger, Heinz . Neuman, Frank . Journal of Guidance, Control, and Dynamics . 23 . 3 . 526–531 . June 2000. 10.2514/2.4559 . 2000JGCD...23..526C .
5. Book: AIAA Guidance, Navigation, and Control 2006 . Target tracking and Estimated Time of Arrival (ETA) Prediction for Arrival Aircraft . Roy, Kaushik . Levy, Benjamin . Tomlin, Claire J. . . AIAA2006-6324 . August 2006.
6. Airport Gate Scheduling with Time Windows . Lim, A. . Rodrigues, B. . Zhu, Y. . Artificial Intelligence Review . 24 . 1 . 2005 . 5–31 . 10.1007/s10462-004-7190-4. 19496597 .
7. Book: Xiong, Bo . Luh, Peter B. . Chang, Shi Chung . Group Elevator Scheduling with Advanced Traffic Information for Normal Operations and Coordinated Emergency Evacuation . Robotics and Automation (ICRA 2005) . April 2005 . . 1419–1424.
8. Book: Estimated Time of Arrival (ETA) Based Elevator Group Control Algorithm with More Accurate Estimation . Rong, Aiying . Hakonen, Henri . Lahdelma, Risto . December 2003 . July 11, 2012 . Turku Centre for Computer Scienceo . 952-12-1289-6.