On March 23, 1995, at 1600 hours Pacific standard time, the pilot of a Piper PA-38-112, N23680, experienced a hard landing on runway 29L at Torrance, California. The aircraft, operated by South Bay Aviation in Torrance, was substantially damaged and the pilot was not injured. Visual meteorological conditions existed at the time. The winds were from 250 degrees at 18 knots. The pilot was on a local pleasure flight and had departed the Torrance airport about 35 minutes earlier. The pilot indicated in his report that he was making a full flap landing to runway 29L at an indicated airspeed of 65 knots. When directly over the runway threshold at a low altitude, the pilot experienced a sudden downdraft and the aircraft landed hard on the main landing gear with the tail hitting the runway. The pilot was able to clear the runway and taxi to the ramp area. The pilot reported no mechanical problems with the aircraft prior to the landing.