Definition
VXSE is the airspeed that produces the greatest gain in altitude per unit of horizontal distance traveled in a multi-engine airplane operating with one engine inoperative. It is published in the Pilot's Operating Handbook and is used when maximum altitude gain over the shortest ground distance is needed after an engine failure, such as clearing an obstacle on departure.
Plain English
The speed that gives you the steepest possible climb after one engine has quit on a twin. You trade forward speed for height gained over a short distance — useful when something is in the way ahead.
Context Anchor
Seen in multiengine airplane performance information and engine-out climb discussions.
Derivation
V is the standard aviation symbol for a velocity (speed). X comes from the existing single-engine term VX, the best angle-of-climb speed. SE stands for single-engine, meaning only one engine is producing thrust. Together: the VX speed when flying single-engine.
Why Pilots Care
It provides the steepest possible climb path to clear obstacles when an engine fails after takeoff.
Intuition Check
Best angle does not mean the fastest climb over time. It means the most height gained for the distance traveled across the ground.
Example Sentence 1
After losing the right engine just past the runway end, the pilot pitched for VXSE to clear the tree line ahead before transitioning to VYSE.
Example Sentence 2
The instructor had the student demonstrate a VXSE climb during the multi-engine checkride prep.