Definition
A condition in which the airplane's engine has stopped producing usable power and cannot be restored to operation in flight, requiring the pilot to glide the airplane to a forced landing.
Plain English
The engine has fully quit and will not restart, so the airplane has to be flown down to a landing without power.
Context Anchor
Encountered in emergency procedures and night flying training, especially when discussing what to do if the engine quits after dark.
Derivation
Complete means total or whole. Failure means something has stopped doing its required job. Together, the phrase means the engine has totally stopped doing its job of providing power for flight.
Why Pilots Care
Requires immediate transition to a glide, precise airspeed control, and selection of a landing site without the option of go-around or powered maneuvering.
Grounding Statement
The key idea is simple: the airplane can still be controlled, but the engine is no longer helping it stay in the air.
Intuition Check
Do not confuse a complete engine failure with rough running or reduced power. Complete means no usable engine power, not just poor engine performance.
Example Sentence 1
After a complete engine failure on the climb-out, the pilot lowered the nose to maintain best glide speed and turned toward the lighted area off the departure end of the runway.
Example Sentence 2
At night the pilot used cockpit instruments to confirm the complete engine failure before turning toward the nearest lighted runway.