Definition
The high-velocity exhaust stream of hot gases discharged rearward from a jet engine during operation, capable of producing strong, turbulent winds behind the aircraft that can damage equipment, upset other aircraft, and injure people on the ground.
Plain English
The powerful blast of air shooting out the back of a jet engine. Even at low power settings it can knock people over, flip light aircraft, and toss loose objects across a ramp.
Context Anchor
You will see this term in airport ground operations, ramp safety, taxi instructions, and warnings about staying clear behind jet aircraft.
Derivation
‘Jet’ comes from the French jeter, meaning ‘to throw,’ and ‘blast’ comes from Old English blǣst, meaning ‘a strong gust of wind.’ Together the term literally means ‘a thrown gust’ — which is exactly what a jet engine produces out the back.
Why Pilots Care
Jet blast can damage nearby aircraft, ground equipment, and injure personnel, requiring strict distance buffers on airports.
Grounding Statement
Picture standing behind a large jet as the engines power up: the air behind it can become a forceful, hot wind strong enough to move unsecured objects.
Intuition Check
Jet blast does not mean an explosion. Here, “blast” means a powerful rush of exhaust air coming from a running jet engine.
Example Sentence 1
Ground control instructed the Cessna to hold short of the taxiway intersection until the departing 737 was clear, to avoid jet blast.
Example Sentence 2
Ground handlers positioned themselves forward of the wing to stay outside the zone affected by jet blast during engine run-up.