Junzi Sun, Ph.D.

Open-source projects (selected) View more on GitHub

Active OpenAP: Open Aircraft Performance Model
OpenAP is a fully open-source aircraft performance and emission model, covering kinematic properties, thrust, drag, and fuel flow rates, all built on open data. The repository provides the OpenAP databases together with a Python implementation for aircraft performance computations.
Active OpenAP.top: Open Flight Trajectory Optimizer
An open-source flight trajectory optimizer based on direct collocation. It accounts for meteorological conditions, handles individual or combined flight phases, and supports conventional fuel and cost-index objectives as well as climate-based objectives using global warming or temperature potentials.
Active fastmeteo: A super fast library to obtain meteorological data for flights
A Python package that retrieves meteorological data for flight trajectories. It uses Analysis-Ready, Cloud Optimized (ARCO) ERA5 data from Google Public Datasets (derived from Copernicus ERA5), and returns wind, temperature, humidity, and other parameters. Works in both local and client-server modes, with customizable features and pressure levels.
Active pyModeS: An Open-source Python Mode-S Decoder
pyModeS is a Python library for decoding and encoding Mode S (including ADS-B) messages. It is an open-source project that receives great support and contributions from the aviation community. This Python package can be imported into an existing Python project, and it is also used as a standalone tool to view and save live traffic data.
Active Contrail-Net: Neural networks models for contrail detection and segmentation
An open-source contrail segmentation model in PyTorch. It uses augmented transfer learning, applying image augmentations to a pre-trained ResUNet so the model can be fine-tuned with only a handful of labelled satellite images. A new loss function, SR Loss, further improves detection by exploiting contrail information in Hough space.
Active Meteo-Particle model Python library
A Python library for wind field estimation using the Meteo-Particle model. Indirect wind and temperature measurements are derived from ADS-B and Mode S data and then assimilated into continuous wind and temperature fields, handling the sparse and uneven distribution typical of aircraft-based measurements.
Active The 1090 Megahertz Riddle: A Guide to Decoding Mode S and ADS-B Signals
An open-access book for researchers, engineers, and students on decoding ADS-B and common Mode S messages. The first part covers the background (primary and secondary radar, Mode A/C, Mode S, ADS-B) and the hardware and software needed to receive the signals. The 17 core chapters then walk through each message type in detail, with Python examples throughout.

Projects that are no longer updated

2015 - 2018 World Aircraft Database
Construct a database to search for aircraft IDs (such as ICAO address, and registrations) and related information. It is built in Python / Flask and with data from Flight Radar 24.
2015 - 2019 Flight data processor
A python library to process and analyze ADS-B flight data. It can reconstruct flight trajectories from ADS-B data and identify flight phases.


© Copyright 2026 Junzi Sun