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PATRICK SWAYZE, who is currently undergoing treatment for pancreatic cancer, is spending a lot of time doing one of the things he loves best -- flying.

According to OK!, the 'Dirty Dancing' star and his wife of 33 years, LISA NIEMI, have taken to the air quite a bit lately -- and not just for the trips to and from Stanford University Medical Center where he is being treated.

The magazine reports, for instance, that in just one day last week the couple made their way to various locales throughout California and Nevada for over 11 hours in their 11-seat Beechcraft Super King Air 200.

"Patrick and Lisa share two great passions: planes and horses," a source tells OK!. "And being able to do what they love most -- and do it together -- is helping them to remain as optimistic as possible."