ACR-MLG STARTED AND ABORTED TKOF WITH ANOTHER ACFT ON RWY. ARR MADE GO AROUND.

Narrative

ON TAXIOUT THE RWY 36R WE WERE CLRED FOR TKOF. OBSERVING A COMMUTER ON A 2 MI FINAL; WE ROLLED ONTO THE RWY. THIS IS WHEN WE OBSERVED SMA Y SINGLE ON THE RWY IN POS ABOUT 2000' DOWN THE RWY. WE ABORTED THE TKOF AND CONTINUED THE ROLL TOWARD THE BYPASS/TURNOFF; ANTICIPATING A REQUEST BY THE TWR TO CLR THE RWY KNOWING THAT BOTH ACFT COULD NOT BE AIRBORNE IN TIME. THE TWR HAD BOTH OF US CLR THE RWY AND THE COMMUTER TO GO AROUND. WE HAD ACKNOWLEDGED THE TKOF CLRNC; BUT 2 OF US ENDED UP ON THE RWY AT ONCE. USING MULTIPLE DEP POINTS ON A SINGLE RWY FROM DIFFERENT RAMPS CAN LEAD TO A SITUATION LIKE THIS. SOME SORT OF BACKUP CONFIRMATION OF A TKOF CLRNC OR AN ATIS NOTIFICATION OF MULTIPLE DEP POINTS COULD HELP IN THIS SITUATION. SOME RWYS DO NOT HAVE A CLR VIEW OF ALL ENTRY POINTS DUE TO SLOPE OR TERRAIN. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING: A FEW DAYS AFTER THIS INCIDENT RPTR WAS CONTACTED BY TELEPHONE BY HIS CHIEF PLT. HE WAS INFORMED THAT ENFORCEMENT ACTION WAS BEING CONTEMPLATED BECAUSE THE TWR CLAIMED HE HAD TAXIED ONTO THE RWY AND STARTED TKOF W/O CLRNC. THEY CLAIMED THAT TKOF CLRNC WAS FOR ANOTHER ACFT. RPTR STATED THAT HE AND HIS F/O HAD HEARD 'CLRED FOR IMMEDIATE TKOF;' AND HAD STARTED A ROLLING TKOF. THEY SAW THE SMA ON THE RWY AT D2 AND IMMEDIATELY ABORTED THEIR TKOF. RPTR NOW SPECULATES THAT THEY DID TKOF WITH CLRNC THAT WAS MEANT FOR THE SMA THAT WAS ALREADY ON THE RWY AT THE INTXN. TWR WAS HAVING DIFFICULTY COMMUNICATING WITH THE SMA ON THE RWY. PLACE OF OCCURRENCE WAS LEARNED DURING CALLBACK.