Bartlett Robinson

as Dr. Orva

as Specialist #1

as Buck Slavin

as Benjamin Frank Mahoney, President Ryan Airlines Co.

as District Attorney Milton

as Munsey (uncredited)

as Captain

as Major Hiram Prescott

as Doctor (uncredited)

as General Timberidge

as Mr. Coleman

as Rhodes

as Sen. Black

as Professor

as Col. Bert Wayne

as Professor Victor Newcole

as Oscar the Butler

as Colonel #1 (archive footage)

as Larkin

as Dr. Wyndham