NMAC BTWN A GLIDER JUST N OF HIS GLIDERPORT AT AN ALT WHICH PLACED IT IN THE CLASS B AIRSPACE AND AN ARRIVING B737. THE GLIDER PLT TOOK EVASIVE ACTION TO AVOID A COLLISION.

Narrative

ON AUG/XD/97; I WAS PARTICIPATING IN A GLIDER COMPETITION BASED AT THE TSA GLIDERPORT S OF MIDLOTHIAN; TX. I WAS CLBING TO START ALT IN PREPARATION TO STARTING ON THE COMPETITION TASK FOR THAT DAY. THE STARTING LINE TO BE CROSSED TO BEGIN THE TASK WAS AN E-W LINE THROUGH THE CTR OF THE GLIDERPORT. THE INITIAL POINT FOR STARTING ASSIGNED WAS APPROX 1/2 MI N OF THE GLIDERPORT. AS I WAS CIRCLING TO CLB I SAW A B737 COMING DIRECTLY AT ME. THE JET WAS VERY CLOSE WHEN I FIRST SAW IT. I IMMEDIATELY DOVE TO THE S TO AVOID THE COLLISION. THE JET PASSED BEHIND (N) OF ME AT APPROX THE SAME ALT I WAS AT. ANOTHER GLIDER PLT IN THE SAME VICINITY; BUT SLIGHTLY LOWER; RPTED TO ME THAT THE B737 PASSED DIRECTLY OVER HIM AT THIS TIME ALSO. I ESTIMATE THE TIME FROM FIRST SEEING THE B737 TO IT PASSING BY ME WAS 2-3 SECONDS. SINCE I WAS NOT IN CLASS B AIRSPACE AND THIS COMMERCIAL JET WAS UNDER LCL AIRSPACE CTLR AUTH; THERE MUST HAVE BEEN A SERIOUS MISTAKE MADE BY THE LCL CTLR TO HAVE DIRECTED THIS HIGH SPD JET ACFT THROUGH A VICINITY THAT HAD 20-30 GLIDERS; SPIRALING UP TOWARDS THE CLOUDS. I ESTIMATE THIS JET CAME WITH 1/2 MI OF AT LEAST 15 GLIDERS WHICH ARE ESSENTIALLY STATIONARY OBJECTS CONSIDERING THE SPD DIFFERENCES BTWN THE ACFT TYPES. IT IS MY UNDERSTANDING THAT TSA OFFICIALS AND LCL PLTS BOTH TELEPHONED LCL ATC AUTHS AND CALLED ON ATC FREQ TO WARN OF THE OPS TO TAKE PLACE BUT THESE NOTIFICATIONS WERE NOT HEEDED. ANOTHER ACR JET PASSED THROUGH THE GLIDERPORT AREA AT 5000 FT EARLIER IN THE AFTERNOON PRIOR TO MY NMAC.