Jack Bauer, with the help of Aaron Pierce, knocked out Wolffson's co-pilot John Carruth and posed as a replacement. Once in the air, Bauer threatened Wolffson with a pistol, and the pilot quickly gave into Bauer's demands. Bauer knocked out President Logan's Secret Service escorts with a taser, and upon the chopper's landing, did the same to Wolffson.
Background information and notes
Wolffson's first name, Bryce, is visible on the flight detail that was provided to Jack by Mike Novick.
In a deleted scene from Day 5, the character is called Allan Wolffson. A file is pulled which mentions several facts about him, among them: he was born in Louden, North Dakota on July 19, 1969 and graduated with a high school degree and Bachelor of Science. He spoke English, Spanish and Russian. He was assigned to Fort Gentile before being promoted to Secret Service detail.
In the script for the episode, his first name is also given as "Allan".