Dr. Kevin Klauer was the passenger who caught the whole thing on video and told CNN that what began as a silly sight quickly took a turn for the worse when it looked like it could be unsafe. The airport worker was not yet identified by Tuesday morning.
The catering cart spun in circles until an airport worker quickly intervened, using a piece of heavy equipment to stop the cart.
According to Envoy Air, which is a subsidiary of American Airlines, the cart was parked by a Embraer 140 aircraft for loading beverages onto an outbound flight when a case of water slipped on the gas pedal and sent the cart spinning in reverse.
Witnesses in the doctor's clip could be heard gasping and exclaiming in fright as they watched the scene unfold.
Insane event at ORD. Heads up safety move by a ramp worker!
"There you go!" a fan cried in the background.
In a statement released after the incident, American Airlines officials said they were investigating the mishap.
An employee was injured in the incident. The airline said preliminary reports indicated that the accelerator got stuck and caused the cart to lose control.
American Airlines added that "We appreciate the quick action of our team member who stopped the vehicle". "Safety is our top priority and we are working with our partners to investigate the incident".
His heroics were even enough to land on President Donald Trump's radar.