A Surprise in Texas, the documentary about the quadrennial Van Cliburn piano competition named for Fort Worth’s celebrated gay musician, will air on KERA 13 Wed., Sept. 1. The film, which made the rounds of film festivals earlier this year, including the Dallas International Film Fest, profiles the historic naming of two gold medalists in 2009 — one the youngest ever, one the first blind winner. It will air at 7 p.m. and immediately again at 8:30 p.m.