# Trajectories

Trajectories in AEIC are defined as the operation profile of the aircraft starting at $914\,\text{m}$
($3000\,\text{ft}$) above the departure airport and ending $914\,\text{m}$ above the arrival airport. All
operations below $914\,\text{m}$ relative to the departure/arrival airport is classified as LTO
operations and are represented using ICAO Annex 16 Volume II time-in-modes. AEIC assumes that
a negligible amount of fuel is burned during these operations.

AEIC currently only supports a trajectory simulation method which is very similar to the
legacy ([AEIC v2](<https://zenodo.org/records/6461767>)) trajectory model. In the future,
support for additional trajectory models will be added. Possible additions include more
dynamics-driven non-trapezoidal trajectories, trajectories closer to real flight tracks
based on [ADS-B](<https://www.adsbexchange.com/>) data, and optimized (horzontal, vertical,
speed) trajectories.

```{eval-rst}
.. toctree::
   :maxdepth: 1

   trajectory_data.md
   trajectory_builders.md
   trajectory_stores.md
```