The airplane was destroyed following an inflight fire and subsequent emergency landing at approximately 1455 Central time. The Private pilot, the sole occupant, sustained minor injuries; visual conditions prevailed for the local flight. Shortly after takeoff, the pilot heard a poof come from behind the instrument panel, smelled an odor consistent with an electrical fire, and observed dark gray smoke and flames around his feet. The pilot turned off the master switch; no change was noted. The pilot performed an emergency landing to a cotton field. Shortly after touchdown the airplane nosed over and came to rest in an inverted position.