Definition
A metal duct inside a fixed-shaft turboprop engine that channels the hot, expanding gases from the combustion chamber into the turbine section. It shapes and directs the gas flow so it enters the turbine blades at the correct angle, while also shielding surrounding engine structure from combustion heat.
Plain English
A heat-resistant tube that guides the burning gases out of the combustion area and into the spinning turbine blades, while protecting the engine parts around it from the intense heat.
Context Anchor
Seen in turboprop engine descriptions, especially when identifying the main parts of a fixed-shaft turboprop engine.
Derivation
‘Transition’ comes from the Latin transire, meaning ‘to go across.’ ‘Liner’ refers to an inner sleeve that lines a passage. Together: the inner sleeve that the gases cross through on their way from the combustor to the turbine.
Why Pilots Care
It maintains smooth gas flow to protect turbine blades from thermal stress and ensures efficient conversion of combustion energy into propeller power.
Analogy
Think of it like a heat-resistant funnel inside the engine. It does not make the heat, but it guides the hot flow where it needs to go.
Intuition Check
Do not think of a transition liner as cabin lining or simple padding. In this engine context, it is a hot-gas guide inside the engine.
Example Sentence 1
In a fixed-shaft turboprop, hot gases leave the combustion chamber and pass through the transition liner before reaching the turbine.
Example Sentence 2
The fixed-shaft design routes all gases through the transition liner before they reach the turbine.