joseflys.com is a collection of aviation calculators that run entirely in the browser. Everything works offline as a PWA.

I know most pilots use ForeFlight, SkyDemon, or similar apps, and I'm not trying to compete with those. This started as a learning project to really understand the math behind flight planning, and I figured others might find it useful too.

Some things you can do:

- Wind correction: Calculate heading and ground speed given wind. Useful for understanding the wind triangle.

- Flight planning: Build multi-leg flight plans with fuel calculations, ETAs, waypoints, and climb/descent performance. Export to PDF or Excel.

- TAS/ISA calculators: Convert between indicated and true airspeed, calculate density altitude.

- Takeoff and V-stall: Performance calculators for go/no-go decisions and understanding stall margins.

- LNAV Segments: An educational tool showing how FMS systems approximate great circle routes with constant-heading segments.

Tech: Next.js, TypeScript, GeographicLib for WGS-84 geodesic calculations, World Magnetic Model for magnetic variation. All calculations happen client-side.

The geodesic precision was an interesting challenge. Haversine isn't accurate enough for real navigation, especially at high latitudes or long distances.

It's open source: https://github.com/jfromaniello/joseflys

Happy to answer questions!