Definition
A short, controlled firing of a rocket or spacecraft engine to change the vehicle's velocity, orbit, or trajectory. The duration and direction of a burn determine how much the vehicle's path is altered.
Plain English
A planned, timed engine firing used to push a rocket or spacecraft into a new path or speed.
Context Anchor
You will see this term in flight planning, fuel calculations, performance discussions, and conversations about engine operation.
Derivation
From the Old English 'beornan,' meaning to be on fire. In rocketry the word kept its sense of fuel combustion but became a countable event — 'a burn' — referring to one specific firing of the engine rather than continuous combustion.
Why Pilots Care
Knowing the burn rate lets the pilot calculate range, endurance, and required fuel reserves for safe flight completion.
Intuition Check
Do not assume burn always means an unwanted fire or damage. In fuel planning, burn means the normal use of fuel by the engine.
Example Sentence 1
Mission control scheduled a thirty-second burn to raise the spacecraft into its target orbit.
Example Sentence 2
Higher power settings raised the burn and shortened the time the aircraft could stay airborne.