Definition
A graph showing how much power the engine and propeller can deliver to the airplane across its range of airspeeds in level flight. The curve typically rises from low airspeeds, peaks, and then varies depending on engine and propeller characteristics. It is plotted alongside the power required curve to show where excess power exists for climbing, accelerating, or maneuvering.
Plain English
A line on a chart that shows how much power the engine can produce at each airspeed. Comparing it to how much power the airplane needs at that airspeed tells you whether you have spare power to climb or accelerate.
Context Anchor
Seen in airplane performance discussions, especially when learning how pitch, power, airspeed, and climb performance relate to each other.
Derivation
“Curve” comes from the Latin idea of something bent or curved. In aviation performance, it often means a line on a graph, even if part of the line looks fairly straight. Here, the curve shows how available power changes as airspeed changes.
Why Pilots Care
It shows how much excess power exists for climbs and sets the upper limit for level flight speed when compared against the power required curve.
Grounding Statement
At each airspeed, the curve answers: “How much usable power can this airplane give me right now?”
Intuition Check
Do not read “power available” as simply “where the throttle is set.” It means the usable power the airplane can actually turn into flight at a given airspeed.
Example Sentence 1
At the airplane's absolute ceiling, the power available curve just touches the power required curve, leaving no excess power to climb.
Example Sentence 2
At higher airspeeds the power available curve declines because the propeller converts engine output less efficiently.