Definition
The highest stall speed, in the landing configuration with power off, that an aircraft is permitted to have to qualify within a given certification category. For Light-Sport Aircraft, this limit is 45 knots calibrated airspeed (CAS) at the maximum certificated takeoff weight and most critical center of gravity.
Plain English
It is the slowest flying speed an aircraft is allowed to have before the wing stops producing lift, set as a ceiling by the rules. If the airplane stalls at a speed faster than this limit, it does not qualify for that category.
Context Anchor
Seen in light-sport aircraft rules, aircraft specifications, and discussions of whether an airplane qualifies as a light-sport aircraft.
Derivation
“Maximum” comes from a Latin word meaning “greatest.” “Stall” originally meant a stop or standstill; in aviation, it means the wing has reached the point where it can no longer make enough lift for steady flight. Together, “maximum stall speed” points to the greatest allowed speed at which that stall point may occur.
Why Pilots Care
Determines whether an aircraft qualifies in a regulatory category and directly affects low-speed handling during training and operations.
Grounding Statement
Picture slowing the airplane for landing: the maximum stall speed limit controls how fast the airplane is allowed to be going when it reaches the edge of a stall.
Intuition Check
Maximum stall speed does not mean the airplane’s top speed. It means the highest allowed speed at which the airplane can stall under the specified conditions.
Example Sentence 1
To be certificated as a Light-Sport Aircraft, the airplane's maximum stall speed must not exceed 45 knots CAS in the landing configuration with power off.
Example Sentence 2
The pilot reviewed the maximum stall speed before planning a short-field landing in the training aircraft.