Narrative:

Beautiful sunny VFR. One cessna in downwind 'cleared touch and go' cessna #2 calls ready same runway, 'cleared for takeoff.' commander XXX calls ready at crossing runway. Realizing another IFR inbound was getting close and not wanting to delay the departure, I scanned both runways and cleared the commander for takeoff. The shades were drawn down. Atm and ground controller converging. I noticed cessna #2 climbing out of the ground clutter through the darken shades. Aircraft #2 was instructed to turn sbound as commander was beginning takeoff roll. Both aircraft flew parallel courses. Factors involved was extraneous conversations. The shades being drawn to cut the glare and heat. The departing cessna was observed by the dark shades and tree line. But the biggest factor, I forgot aircraft #2. I'm xx yrs old supervisor well acclimated and current at my supervisory position and time on position. I forgot just for a moment. My scanning through shade failed to allow me to see cessna. I'll never work with shade blocking my 'clear' view of runway again. Those who are rethinking changing ATC retirement age from 56 to 62 had better stop and rethink. I've seen many, many cases of these short term memory loss, never of any serious consequences, but only time will tell. Those who think otherwise are deceiving themselves and playing with others' lives.

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Original NASA ASRS Text

Title: TVC CTLR EXPERIENCED OPERROR WHEN ISSUING TKOF CLRNC TO ACFT DEPARTING FROM XING RWYS.

Narrative: BEAUTIFUL SUNNY VFR. ONE CESSNA IN DOWNWIND 'CLRED TOUCH AND GO' CESSNA #2 CALLS READY SAME RWY, 'CLRED FOR TKOF.' COMMANDER XXX CALLS READY AT XING RWY. REALIZING ANOTHER IFR INBOUND WAS GETTING CLOSE AND NOT WANTING TO DELAY THE DEP, I SCANNED BOTH RWYS AND CLRED THE COMMANDER FOR TKOF. THE SHADES WERE DRAWN DOWN. ATM AND GND CTLR CONVERGING. I NOTICED CESSNA #2 CLBING OUT OF THE GND CLUTTER THROUGH THE DARKEN SHADES. ACFT #2 WAS INSTRUCTED TO TURN SBOUND AS COMMANDER WAS BEGINNING TKOF ROLL. BOTH ACFT FLEW PARALLEL COURSES. FACTORS INVOLVED WAS EXTRANEOUS CONVERSATIONS. THE SHADES BEING DRAWN TO CUT THE GLARE AND HEAT. THE DEPARTING CESSNA WAS OBSERVED BY THE DARK SHADES AND TREE LINE. BUT THE BIGGEST FACTOR, I FORGOT ACFT #2. I'M XX YRS OLD SUPVR WELL ACCLIMATED AND CURRENT AT MY SUPERVISORY POS AND TIME ON POS. I FORGOT JUST FOR A MOMENT. MY SCANNING THROUGH SHADE FAILED TO ALLOW ME TO SEE CESSNA. I'LL NEVER WORK WITH SHADE BLOCKING MY 'CLR' VIEW OF RWY AGAIN. THOSE WHO ARE RETHINKING CHANGING ATC RETIREMENT AGE FROM 56 TO 62 HAD BETTER STOP AND RETHINK. I'VE SEEN MANY, MANY CASES OF THESE SHORT TERM MEMORY LOSS, NEVER OF ANY SERIOUS CONSEQUENCES, BUT ONLY TIME WILL TELL. THOSE WHO THINK OTHERWISE ARE DECEIVING THEMSELVES AND PLAYING WITH OTHERS' LIVES.

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.