Definition
A stainless steel tube installed in the engine nacelle of certain reciprocating-engine aircraft that uses the velocity of exhaust gases to draw cooling air through the engine compartment. The fast-moving exhaust passes through the tube and creates a low-pressure area that pulls air across the cylinders, increasing cooling airflow without relying solely on ram air from forward motion.
Plain English
A metal tube that uses the fast flow of engine exhaust to suck extra cooling air past the engine, helping it stay cool — especially when the aircraft is moving slowly or sitting on the ground.
Context Anchor
Seen in aircraft powerplant maintenance, especially when discussing exhaust systems and engine cooling airflow.
Derivation
From the Latin 'augmentare,' meaning 'to increase' or 'to make larger.' The tube augments — increases — the flow of cooling air beyond what ram air alone would provide.
Why Pilots Care
Augmentor tubes keep cylinder temperatures within limits during low-airspeed operations like climbs and ground runs. A damaged or cracked augmentor tube can reduce cooling airflow and lead to overheating or, in some installations, allow exhaust gas into the cabin heating system.
Analogy
Think of a kitchen range hood: as fast-moving air rushes through the duct, it pulls smoke and steam up with it. The augmentor tube does the same thing — exhaust rushing through the tube pulls cooling air along with it.
Grounding Statement
Picture hot exhaust rushing through a tube and pulling nearby air along with it, helping carry heat away from the engine area.
Intuition Check
An augmentor tube does not add power to the engine. It “augments” the airflow used for cooling.
Example Sentence 1
During the 100-hour inspection, the technician checked the augmentor tubes for cracks and corrosion before signing off the engine.
Example Sentence 2
Proper operation of the augmentor tube kept cylinder head temperatures within limits during the long climb.