Definition
An engine arrangement in which a multi-bladed fan is enclosed inside a cylindrical duct or shroud and driven by a piston engine, turbine, or electric motor to produce thrust. The duct surrounds the fan tips, shaping the airflow through the fan and improving thrust efficiency compared to an open propeller of similar diameter.
Plain English
A propeller-like fan placed inside a tube. The tube channels the air through the fan, producing thrust more efficiently and safely than a regular open propeller.
Context Anchor
Seen in discussions of aircraft propulsion, especially aircraft that use an enclosed fan instead of an open propeller.
Derivation
‘Ducted’ comes from the Latin ductus, meaning ‘a leading’ or ‘channel’ — so a duct is something that guides flow. ‘Fan’ refers to the multi-bladed rotor inside. Together: a fan that pushes air through a guiding channel.
Why Pilots Care
Can deliver higher efficiency and lower noise than open propellers in certain speed ranges and aircraft designs.
Intuition Check
Do not assume a ducted-fan engine is automatically a jet engine. The key idea is the enclosed fan: spinning blades inside a duct produce thrust by pushing air rearward.
Example Sentence 1
The light sport aircraft used a ducted-fan engine, which made it noticeably quieter on the ramp than the propeller-driven trainers parked beside it.
Example Sentence 2
Preflight inspection included checking the duct around the fan for any signs of damage or debris.