Narrative:

I had just relieved the previous controller about 1 min earlier and was trying to establish vertical separation between a previous air carrier departure and a VFR cessna overflt before switching the air carrier over to departure. I was also trying to turn up the radar scope's map and alpha numeric brightness which was very low when aircraft X called ready to go. I scanned the runway, but apparently not far enough on final. I cleared aircraft X for takeoff and resumed adjusting the scope when a short time later aircraft Y, a lear on final and cleared to land by previous controller, asked what aircraft X was doing. I looked up and saw the lear on short final with aircraft X past the hold line with his nose over the runway edge. I told the lear to go around. The lear did not respond and continued to land. The lear apparently thought that aircraft X was at fault and said he caused a runway incursion. It was my fault. Had I set up the scope prior to taking the position, or simply told aircraft X to hold short while I was busy with the departing traffic and VFR traffic, and taken an extra moment to fully settle in to the position, this incident would not have occurred. Aircraft X saw the lear on short final and stopped, but since he was past the hold line, an incident occurred. I've heard that the first few mins and last few mins on position are when most incidents happen in ATC, and now I know from experience. Be extra vigilant when taking the position and don't let the fact that there is very little traffic lull you into letting your guard down.

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Original NASA ASRS Text

Title: LCL CTLR HAD JUST ASSUMED THE POS, WAS DISTR WITH OTHER DUTIES. CLRED ACFT X FOR TKOF. FORGOT ABOUT ACFT Y WHO WAS ON APCH. ACFT Y LANDED LONG OVER ACFT X.

Narrative: I HAD JUST RELIEVED THE PREVIOUS CTLR ABOUT 1 MIN EARLIER AND WAS TRYING TO ESTABLISH VERT SEPARATION BTWN A PREVIOUS ACR DEP AND A VFR CESSNA OVERFLT BEFORE SWITCHING THE ACR OVER TO DEP. I WAS ALSO TRYING TO TURN UP THE RADAR SCOPE'S MAP AND ALPHA NUMERIC BRIGHTNESS WHICH WAS VERY LOW WHEN ACFT X CALLED READY TO GO. I SCANNED THE RWY, BUT APPARENTLY NOT FAR ENOUGH ON FINAL. I CLRED ACFT X FOR TKOF AND RESUMED ADJUSTING THE SCOPE WHEN A SHORT TIME LATER ACFT Y, A LEAR ON FINAL AND CLRED TO LAND BY PREVIOUS CTLR, ASKED WHAT ACFT X WAS DOING. I LOOKED UP AND SAW THE LEAR ON SHORT FINAL WITH ACFT X PAST THE HOLD LINE WITH HIS NOSE OVER THE RWY EDGE. I TOLD THE LEAR TO GO AROUND. THE LEAR DID NOT RESPOND AND CONTINUED TO LAND. THE LEAR APPARENTLY THOUGHT THAT ACFT X WAS AT FAULT AND SAID HE CAUSED A RWY INCURSION. IT WAS MY FAULT. HAD I SET UP THE SCOPE PRIOR TO TAKING THE POS, OR SIMPLY TOLD ACFT X TO HOLD SHORT WHILE I WAS BUSY WITH THE DEPARTING TFC AND VFR TFC, AND TAKEN AN EXTRA MOMENT TO FULLY SETTLE IN TO THE POS, THIS INCIDENT WOULD NOT HAVE OCCURRED. ACFT X SAW THE LEAR ON SHORT FINAL AND STOPPED, BUT SINCE HE WAS PAST THE HOLD LINE, AN INCIDENT OCCURRED. I'VE HEARD THAT THE FIRST FEW MINS AND LAST FEW MINS ON POS ARE WHEN MOST INCIDENTS HAPPEN IN ATC, AND NOW I KNOW FROM EXPERIENCE. BE EXTRA VIGILANT WHEN TAKING THE POS AND DON'T LET THE FACT THAT THERE IS VERY LITTLE TFC LULL YOU INTO LETTING YOUR GUARD DOWN.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.