Definition
The disturbed, accelerated mass of air pushed rearward by a turning propeller. This airflow is faster, more turbulent, and rotates in a corkscrew pattern around the fuselage, striking the tail surfaces and other parts of the airframe behind the propeller.
Plain English
The fast, swirling stream of air thrown backward by the spinning propeller. It hits the back of the airplane and affects how the tail surfaces respond.
Context Anchor
In an elevator trim stall discussion, propwash matters when power is added and the stronger airflow over the tail can make the nose rise more strongly.
Derivation
A simple compound of 'prop' (propeller) and 'wash' (a disturbed flow of water or air left behind by something moving through it, as in the wake of a boat). The term captures the idea of a trailing, churned-up flow.
Why Pilots Care
Propwash supplies airflow over the horizontal stabilizer and elevator at low airspeeds; its sudden reduction can cause loss of pitch control and an uncommanded nose-up pitch.
Analogy
Think of standing behind a strong fan. The air behind it is not calm; it is a fast, uneven stream. Propwash is that same idea, produced by the airplane’s propeller.
Intuition Check
Propwash does not mean dirt, water, or exhaust from the propeller. It means the moving air pushed backward by the spinning propeller.
Example Sentence 1
When full power was applied for the go-around, the propwash over the elevator increased the pitch-up tendency, requiring firm forward pressure on the yoke.
Example Sentence 2
Full power increases propwash over the tail, helping the pilot maintain elevator authority at very low airspeeds.