Theo Oberon
From Battlestar Wiki, the free, open content Battlestar Galactica encyclopedia and episode guide
Dash is the callsign of a pilot who was assigned to Galactica.
Dash's Viper was seen in the hangar when Captain Lee Adama and Billy Keikeya were waiting for Laura Roslin to appear for the escape (Resistance).
Dash was killed sometime prior to the destruction of Scar and mentioned by Captain Kara Thrace during a speech about dead Galactica pilots. (Scar)