Rick Hendrick, owner of Hendrick Motorsports, yesterday said he sustained four broken ribs, a broken clavicle and a concussion when his seat broke loose during a runway-departure accident on October 31. According to the NTSB, the Gulfstream G150 went off the end of the runway at Key West International Airport on landing, collapsing the nose landing gear and causing airframe structural damage. Nine others aboard, including two pilots, suffered minor cuts and bruises. An NTSB investigation is ongoing.