Plain English Meaning

Something is blocking or partly blocking the air that needs to flow through the engine area, so less air gets through than should.

Full Definition

Any blockage, narrowing, or obstruction in the path of air moving through the engine compartment, induction system, or cooling passages that reduces the volume of air able to pass through. In the context of the engine compartment, common causes include debris, bird or insect nests, deformed cowling baffles, blocked air filters, or contamination of the induction inlet.

Context Anchor

Seen during preflight, engine inspection, and discussions of engine cooling and cowling design.

Why Pilots Care

Unresolved airflow restriction raises cylinder head and oil , risking engine damage or in- shutdown.