The aviation knowledge library
Clear, plain-English explanations of the aeronautical concepts you need to know — every page grounded in the official, public-domain FAA handbooks and cites its source. Pick your certificate below, or search any topic. Read to understand the why, then test yourself with free questions.
Browse by certificate
Choose the rating you’re studying for to see its topics, organized by subject.
General Aeronautical Knowledge
Core concepts every pilot shares — the foundations.
Private Pilot
Aerodynamics, airspace, weather, and the rules for your PPL written.
Sport Pilot
Light-sport rules, privileges, and the knowledge for the Sport written.
Instrument Rating
Approaches, holds, clearances, and IFR weather for the Instrument written.
Commercial Pilot
Commercial maneuvers, complex systems, and high-altitude operations.
Multi-Engine
Critical engine, Vmc, one-engine-inoperative performance, and multi-engine systems and procedures — the aerodynamics and decision-making of flying twins.
Airline Transport Pilot
Air-carrier operations, advanced aerodynamics, and ATP-level systems.
Fundamentals of Instructing (FOI)
The learning & teaching process, assessment, lesson plans, and risk-management instruction — the FOI knowledge test, grounded in the Aviation Instructor’s Handbook (FAA-H-8083-9).
Aircraft Dispatcher
Operational control, dispatch release, fuel & alternate planning, and the ADX knowledge areas — from the dispatcher’s seat.
Flight Engineer
Turbine and reciprocating powerplants, transport-aircraft systems, performance, and weight & balance — the FE knowledge tests, grounded in the FAA powerplant, airframe, and weight-and-balance handbooks.
Flight Instructor (CFI)
Teaching aerodynamics and flight maneuvers, common student errors, and how to deliver the flight lesson.
Part 107 (Drone)
Airspace, LAANC, Remote ID, and the rules for commercial drone ops.
AMT — General
Shared maintenance knowledge: math, physics, materials, and regulations.
AMT — Airframe
Structures, systems, and airframe inspection for the Airframe written.
AMT — Powerplant
Reciprocating and turbine engines, propellers, and powerplant systems.
Aviation Weather
A dedicated weather library mirroring the FAA Aviation Weather Handbook — atmosphere to thunderstorms, icing, turbulence, reports, and forecasts.
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Take a free practice test →Explanations are original summaries grounded in the public-domain FAA handbooks and cite their source. They are study aids, not a substitute for the official handbooks or regulations.