Definition
A type of thrust reverser used on turbofan engines that redirects fan air forward through a set of curved vanes (the cascade) when activated. Sliding sleeves on the engine nacelle move aft to expose the cascade vanes and block the normal rearward fan airflow, turning that airflow forward to produce reverse thrust. Cascade reversers act on the bypass (fan) air only, not the hot core exhaust.
Plain English
A reverse-thrust system that, when switched on after landing, slides part of the engine cover backwards and sends the engine's fan air forward through curved vanes. Pushing air forward slows the airplane down.
Context Anchor
Seen in jet airplane systems discussions, especially when learning how thrust reversers help slow the airplane during landing rollout.
Derivation
Cascade' comes from the Italian 'cascata,' meaning a small waterfall — a series of steps that redirects flowing water. The vanes in a cascade reverser similarly redirect flowing air through a series of curved guides, turning it from rearward to forward.
Why Pilots Care
Shortens landing distance and reduces brake wear, especially useful on wet or slippery runways.
Analogy
Think of placing angled louvers in front of a fan so the air no longer blows straight back. The air is turned and sent in a different direction, which changes the force the fan produces.
Intuition Check
A cascade reverser is not a system that reverses the engine’s rotation. It redirects airflow so the engine’s push helps slow the airplane.
Example Sentence 1
After touchdown, the captain selected reverse and the cascade reversers deployed, sending fan air forward to help slow the aircraft.
Example Sentence 2
On a short wet runway the pilot relied on the cascade reversers to help stop within the available distance.