TKOF WITH NOSE TOW BAR STILL ATTACHED.

Narrative

ACFT WAS PARKED INSIDE HANGAR OVERNIGHT AT A LARGE NATL FBO. I ORDERED THE ACFT TO BE PULLED OUT OF THE HANGAR AND READIED FOR FLT AT APPROX XA00 LCL TIME. PLANE WAS PULLED OUT AND HAD COFFEE AND ICE PUT IN; AND WAS PRESUMED READY TO FLY. PLANE WAS PLACED AT FAR SIDE OF RAMP WHERE THERE WAS NO LIGHT FROM THE BLDG. I ARRIVED AT ARPT; WALKED AROUND ACFT; REMOVED ENG PLUGS; REMOVED CHOCK FROM MAIN GEAR OF ACFT; LOCKED THE NOSE BAGGAGE COMPARTMENTS AND NEVER SAW THE TOW BAR WHICH WAS PAINTED DARK BLUE AND BLENDED INTO THE DARK RAMP. I TAXIED OUT AND NEVER FELT OR HEARD THE TOW BAR ON THE NOSE GEAR UNTIL LIFT OFF; WHEN I HEARD A LOUD THUMP AND FELT A SHUDDER. I PRESUMED THAT I HAD BLOWN A NOSE TIRE ON LIFT OFF AND RETURNED IMMEDIATELY TO A LNDG. UPON T/D THE ACFT IMMEDIATELY VEERED SHARPLY TO THE RIGHT AND I USED FULL DIFFERENTIAL BRAKING TO KEEP THE ACFT STRAIGHT ON THE RWY. UPON SHUTDOWN; I DISCOVERED THAT THE TOW BAR WAS STILL ATTACHED TO THE NOSE GEAR. DAMAGE CONSISTED ONLY OF 6 BROKEN SHEAR BOLTS IN THE NOSE STEERING COLLAR. IT COULD HAVE BEEN WORSE.