Plain English Meaning
The official rulebook that says exactly what a student has to know, manage, and be able to do in the airplane to pass their written test and checkride for a given certificate or rating.
Full Definition
An FAA-published document that defines the knowledge, risk management, and flight proficiency standards an applicant must meet to earn a specific pilot certificate or rating. The ACS integrates the aeronautical knowledge tested on the written exam with the skills tested on the practical (checkride) and the risk management judgment expected of a competent pilot.
Context Anchor
Pilots and instructors use the ACS during training, lesson planning, and for an FAA .