About PFactor

Who I am, and how I put this material together.

I'm Charath Ranganathan, a certificated flight instructor (CFII) in Southern California. I teach at AACIT, the Aero Association of California Institute of Technology, the Caltech/JPL flying club based at San Gabriel Valley Airport.

Everything on this site is free. My goal is simple: ground school material that is short enough to actually finish, honest about its sources, and useful whether you train with me or anywhere else.

How I build the material

Every lesson cites FAA primary sources: the Pilot's Handbook of Aeronautical Knowledge, the Airplane Flying Handbook, the Aviation Weather Handbook, the FAR/AIM, and the Airman Certification Standards.
I size each lesson to a single focused sitting and end it with a quiz, because retrieval is what builds retention.
Diagrams and photos show real airplanes, mostly the Cessna 172 you will likely train in.

Licensing

My original content is licensed under Creative Commons Attribution-NonCommercial-ShareAlike 4.0. Photos and drawings sourced from Wikimedia Commons are credited in place and carry their own licenses.

A necessary disclaimer This site supports ground study. It is not flight instruction, and nothing here overrides your instructor, the current FARs, or your airplane's POH.