Terrifying footage captures the moment a plane's engine violently shakes while in mid-air.
Passengers on board United Airlines flight 293 from Denver to Orlando on Sunday may have feared the worst upon seeing the problem with the plane's left-side wing engine.
While thousands of feet in the air, the engine could be seen rapidly bouncing up and down.
One passenger filmed the frightening incident on their mobile phone.
Passengers shared messages they received from United Airlines after the plane returned to Denver.
The first message read: “We know returning to the airport wasn’t part of your plans today, so we greatly appreciate you hanging in there!
"Our maintenance team needs to address a technical issue with an engine on your plane before we depart again. We’re doing our best to get you on your way as soon as possible.”
A second message said: "Our maintenance team needs more time than we thought to finish their work. To get you on your way, we assigned your flight a new plane arriving shortly from Los Angeles. Once we've finished getting the cabin ready, we'll begin boarding at Gate B47.
"Delays are very frustrating, and we greatly appreciate your patience!"
United Airlines described the engine problem as a "mechanical issue".
"United flight 293 from Denver to Orlando returned to the airport due to a mechanical issue with one of the engines," a spokesman for the company told Mail Online.
The company added passengers on board the flight disembarked the plane at Denver and then boarded another plane.
No injuries were reported.
