THE AIRPLANE WAS RETURNING FOR LANDING FROM A LOCAL NIGHT FLIGHT. THE PILOT WAS ADVISED SOME RUNWAY LIGHTS WERE INOPERATIVE AND CAR LIGHTS WOULD BE USED TO ILLUMINATE THE RUNWAY. THE PILOT HAD DIFFICULTY FINDING THE AIRPORT. HE ABORTED HIS FIRST APPROACH, BECAUSE IT DID NOT LOOK RIGHT. ON HIS SECOND APPROACH HE SAID, 'EVERYTHING LOOKED GOOD, I FLARED, AND THEN THE PLANE SUDDENLY HIT THE RUNWAY HARD. I TOOK OFF AGAIN AND MADE ANOTHER ATTEMPT...I MADE MY APPROACH, LANDED ON THE RUNWAY A GOOD DISTANCE DOWN THE RUNWAY AND PROCEEDED TO DIRECT THE AIRCRAFT TO THE GRASS.' AN EXAMINATION OF THE AIRPLANE BY THE FAA REVEALED BUCKLING OF THE FIREWALL. THE PILOT HAD A TOTAL OF 103 FLIGHT HOURS WITH 7 HOURS IN THIS MODEL. HE HAD A TOTAL OF 4 HOURS NIGHT TIME. HE HAD FLOWN 2 HOURS IN THE LAST 90 DAYS AND 1 HOUR IN THE LAST 30 DAYS.