Definition
A helicopter autorotation begun at an altitude at or below 25 feet above the ground (AGL). It is a power-off descent and landing maneuver initiated so close to the surface that there is no time or altitude available to establish a steady autorotational descent before touchdown.
Plain English
An emergency landing technique used when a helicopter loses engine power very close to the ground, so the pilot has only seconds and almost no height to work with before touching down.
Context Anchor
Seen in helicopter training, emergency landing practice, and air traffic discussions involving helicopter operations near an airport or landing area.
Derivation
‘Autorotation’ comes from Greek ‘auto-’ (self) and Latin ‘rotare’ (to turn) — the rotor turns itself, driven by air flowing up through the disc rather than by engine power. ‘Low level’ simply specifies that the maneuver begins very near the ground.
Why Pilots Care
Helicopter pilots must master this to survive sudden engine failure when already near the ground, where there is no time to gain speed or altitude before touchdown.
Intuition Check
Low level does not mean easy or basic here. It means the autorotation begins at a low height above the ground.
Example Sentence 1
When the engine quit during a hover taxi at 15 feet, the instructor demonstrated a low level autorotation, cushioning the landing with collective.
Example Sentence 2
After the engine quit on short final, the pilot entered a low level autorotation and touched down safely on the runway numbers.