Definition
The airspeed that produces the greatest gain in altitude per unit of horizontal distance traveled. At this speed, the airplane climbs most steeply, clearing obstacles in the shortest ground distance after takeoff.
Plain English
The speed that gets you the most height for the least distance forward. You use it when something is in the way and you need to climb steeply to get over it.
Context Anchor
You will see this term in takeoff performance, short-field takeoffs, obstacle clearance, and airplane manual speed charts.
Derivation
The phrase describes itself: the angle of climb is the angle between the flight path and the ground. 'Best' here means steepest. The speed labeled VX is the one that produces that steepest angle.
Why Pilots Care
Choosing this speed ensures the airplane clears obstacles on departure; using a higher speed flattens the climb path and may cause contact with terrain or wires.
Intuition Check
Do not read “best angle” as “the highest nose-up attitude.” Here, it means the steepest climb path over the ground: the most height gained in the least forward distance.
Example Sentence 1
After takeoff from the short field, the pilot held VX until clear of the trees at the end of the runway.
Example Sentence 2
Once clear of obstacles the pilot accelerated from best angle of climb speed to best rate of climb speed for a more efficient ascent.