Definition
The position of the landing gear at a given moment of flight — either extended (down and locked) or retracted (up and stowed). On performance charts, gear configuration is one of the variables that affects stall speed, drag, and overall aircraft performance.
Plain English
Whether the landing gear is down or up. The chart treats these as two different conditions because the airplane behaves differently in each.
Context Anchor
Seen in aircraft performance charts when choosing the correct stall speed information for the way the airplane is actually set up.
Derivation
‘Configuration’ comes from the Latin configurare, meaning ‘to shape together.’ In aviation, it refers to how the airplane is currently ‘shaped’ — gear down or up, flaps in or out — because each shape produces different aerodynamic behaviour.
Why Pilots Care
Alters stall speed and drag, which must be accounted for in performance calculations to maintain safe margins during takeoff, approach, and landing.
Intuition Check
Do not read gear configuration as the airplane’s general equipment setup. In this context, gear means landing gear, and configuration means its position or condition for the chart.
Example Sentence 1
The stall speed chart shows two values for each bank angle — one for the gear-down configuration and one for the gear-up configuration.
Example Sentence 2
Lowering the gear changes the configuration and increases stall speed due to added drag.