Definition
The speed at which an aircraft can be safely taxied on the ground while remaining under full positive control of the pilot, allowing the airplane to be stopped promptly with normal use of the brakes. There is no fixed numerical value; it varies with surface conditions, aircraft type, congestion, and proximity to obstacles, but is generally a slow walking-to-jogging pace in congested ramp areas and slightly faster on open taxiways.
Plain English
A taxi pace slow enough that the pilot stays in complete control and can stop the airplane quickly without slamming on the brakes.
Context Anchor
You will see this after landing, when the airplane has slowed down and is leaving the runway or moving toward parking.
Derivation
“Taxi” in aviation comes from the idea of a taxi-cab moving under its own power along the ground. An airplane “taxies” when it moves on the ground under its own power instead of flying. “Normal” here means usual and appropriate for the situation, not a single exact speed.
Why Pilots Care
Keeps the airplane under positive control on the ground and reduces the chance of runway incursions, taxiway excursions, or collisions with other traffic or objects.
Intuition Check
Do not read “normal” as a fixed number that is the same for every airplane or airport. Here, “normal taxi speed” means a safe ground speed for the airplane, surface, traffic, and turning situation.
Example Sentence 1
After clearing the runway, the pilot reduced power and maintained a normal taxi speed while heading to the parking ramp.
Example Sentence 2
The instructor reminded the student to hold normal taxi speed on the ramp so the airplane could be stopped quickly if another aircraft appeared.