DENVER (CBS4) – Engine failure on a commercial aircraft is not common, but it also isn’t unheard of. United Airlines flight 328 suffered some kind of problem on Saturday as it left Denver for Honolulu.

The flight had to return to Denver International Airport.

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(credit: CBS)

Even though the images taken by passenger are shocking, Kevin Kuhlmann the Associate Chair of the Aviation and Aerospace Science Department at Metro State University Denver says dual engine airplanes are able to fly for a long time with only one engine.

“That’s got to be the case because it’s not uncommon for an engine to either fail or there is something going on where you shut the engine down, precautionary just in case,” he said.

BROOMFIELD, CO – FEBRUARY 20: A large piece of what appears to the outside of an airplane engine sets in the median along Sheridan Blvd near E. 13th Ave February 20, 2021. A United 777 airplane had an engine fail above and scattered parts over the entire nearby neighborhood and Broomfield Commons Park. (Photo by Andy Cross/MediaNews Group/The Denver Post via Getty Images)”n”n

Kuhlmann says airline pilots and crew members are ready for all sorts of inflight emergencies – even losing an engine.

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“The pilots are very well trained for it and know how to deal with it.”

He does admit there have been incidents in the past that sound similar to Saturday’s events, like in February of 2018 when United Airlines flight 1175, a Boeing 777, which left San Francisco for Honolulu. The engine caught fire and started spewing debris about 36 minutes from the Honolulu airport.

BROOMFIELD, CO – FEBRUARY 20: A piece of airplane engine debris at Broomfield Commons Park February 20, 2021. A United 777 airplane had an engine fail above and scattered parts over the entire nearby neighborhood and Broomfield Commons Park. (Photo by Andy Cross/MediaNews Group/The Denver Post via Getty Images)

“Over the last two or three years there have been some incidents,” he said.

He cautions against jumping to any conclusions about the integrity of the aircraft in Denver’s incident or its engines.

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“We don’t know yet. It’s too early,” Kuhlmann said. “They haven’t looked at all the possibilities. This could be mechanical in which there was a structural failure or there could be an external factor such as a bird strike or foreign object damage.”

Michael Abeyta