(CNN) A United flight made an emergency landing in Honolulu on Tuesday after a piece of the cover came off the plane's right engine, United spokesman Charles Hobart said.

"Scariest flight of my life," passenger Maria Falaschi‏ tweeted.

The incident occurred less than an hour before United Airlines flight 1175 was set to land in Honolulu. The plane was flying over the Pacific Ocean from San Francisco.

Passenger Erik Haddad recorded video of the engine as the plane flew over the Pacific.

"That looks bad, plane and simple," he wrote on Twitter describing the sight of pieces of metal missing from the front of the engine cowling.

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