Harrison began flight training in the 1960's at Wild Rose Airport in Wild Rose, Wisconsin flying in a TriPacer, but at $11 an hour he was unable to continue the training.
His interest returned in the mid-1990's when he bought a used Gulfstream II and asked one of his pilots, Terry Bender, to give him flying lessons. They started out flying a Cessna 182 out of Jackson, Wyoming. He later switched to Teterboro, New Jersey flying a Cessna 20.

He is the owner of the following aircraft: a De Havilland Canada DHC-2 Beaver (N28S), an Aviat Husky A-1B, a Cessna Citation CJ3, a Beech Bonanza B36T3, a Cessna 208 B Grand Caravan, a 1929 Waco Taperwing and a Bell 407 helicopter.

On several occasions he has personally provided emergency helicopter services at the behest of Jackson Hole authorities, in one instance rescuing a hiker overcome by dehydration.

He is the current Honorary Chairman of the Experimental Aircraft Association's Young Eagles program, dedicated to give children a chance to fly in a general aviation airplane for free.