The story
XCFinder was born in 2021 from a simple observation as an amateur paraglider pilot: I had a hard time quickly finding the “classic” routes for a bivouac flight between Chamonix and Gréolières. Of course there’s the excellent thermal.kk7.ch, but (in my opinion) it contains too much information to build a concrete itinerary. I needed to visualize real tracks, ideally in my category. XCFinder therefore displays all tracks at the same time from a takeoff or a French department, with all the necessary filters (or almost!).
In summer 2025, I picked the project back up and completely rebuilt the site: I wanted to analyze flights in more detail. Extracting the prospecting, transition, cruising and thermalling phases makes the flight dynamics obvious at a glance. That’s done with a fairly simple algorithm that I’ll describe below.
I also sometimes replay my flights in 3D on the now-defunct ayvri and, more recently, sportstracklive.com. But I was looking for a camera movement much closer to a chase cam. I wanted to avoid having to manually rotate the camera every time the pilot changed heading…
How does it work?
Tracks
Tracks (.igc) and raw flight data come from two sources.
- Flights uploaded directly on the site
- and flights coming from the FFVL. For performance reasons I filter out French league flights under 50 km.
Flight phases
A flight is mainly made of 4 phases: prospecting, thermalling, transition and cruising. In the computation, I split and classify the flight every 30 seconds. A segment is considered “circling” if the turn rate is at least 6°/s. Then:
- If “circling”:
- If the average vario is positive (> +0.1 m/s): thermal.
- Otherwise: prospecting (you turn but you don’t climb).
- If “straight” and fast enough (> 15 km/h):
- If the vario is clearly negative (< −1 m/s): transition (crossing sinking air).
- Otherwise: cruise (straight glide, low sink or level, advancing on a “working” line).
- Otherwise: prospecting (default when it doesn’t clearly match the other cases).
Post-processing: a “thermal” segment that’s too short (< 30 s) is reclassified as prospecting.
It’s somewhat subjective, but a flight can be considered “efficient” (or simply more precise) when glide phases (transition + cruising) and thermals connect quickly—i.e. when prospecting is minimal. Highlighting this helps put the raw average-speed number into context.
Weather
All data comes from open-meteo.com. These are observed values. Wind is provided at 10 m and 100 m above ground (AGL), temperature at 2 m. Cloud cover is given in %, by layer (low L, mid M, high H). This helps provide context for the flight.
GPS navigation
Most vario/GPS devices offer a navigation mode that lets you follow a route planned in advance using software like SeeYou / FlyXC. This can be useful for target distances, but also to reproduce dream flights :)
Navigation mode lets you extract a track’s turnpoints in two clicks and export them in a format compatible with your device. Handy. Disclaimer: this is an aid for responsible pilots and it does not take the original flight conditions into account at all ;)
Who am I?
My name is Sébastien Picot. I’ve been paragliding for 15 years youtube.com/@sebap_xc and I’m also a web engineer capsule5.com. This project brings together two passions, and I’d be happy if this app proves useful to as many people as possible. We learn from the best—this is also the site’s motto—and I’d like to highlight its educational purpose above all.
Thanks…
To everyone who took the time to read this, and to everyone who helps and supports the existence and sharing of this site—thank you!
Fly safe & happy XC
