N2318T

According to the pilot/owner of the Piper PA28-140, he completed a left base turn to final for landing on Runway 17. He reduced power, "attempted to flare," and the airplane landed "very" hard. He stated that the airplane "appeared to be porpoising" and bounced hard two more times before it slid to a halt. The pilot reported that there were no mechanical deficiencies with the airplane. He concluded, "My best guess is that my speed was too high and I was trying to land by instinct rather than watching the airspeed."The pilot reported that the winds were from 180 degrees at 4 knots.