Narrative:

I was working sck tower, all positions combined at the flight data position. I had 3 aircraft on approach when the small aircraft X requested a clearance to taxi and pick up an IFR for an approach at sck, then IFR to fat. An small aircraft reported missed at the same time small aircraft X was making his request. I told the small aircraft to contact departure and then advised small aircraft X I had his clearance. I issued the clearance for the sck airport and told him to expect clearance for fat on the downwind. In issuing the clearance I gave a wrong initial heading of 200 degree instead of 050 degree. The pilot read it back and I missed it on the readback as I was typing in the aircraft number and type into the ARTS system. Small aircraft X took off and turned to a heading of 200 which brought him back over the airport. Small aircraft Y was climbing out on runway heading and they were less than 500 ft altitude apart and less than 1/2 mi. They were both IMC. Small aircraft X was turned away by the approach controller. One of the contributing factors is that when local is combined at ground, the ground frequency is extremely weak. This plus the diversion of computer entries and listening only to what I wanted to hear could have developed into disaster. Possible solutions: have maintenance increase ground control volume, write clearance on blank strip even when working alone as memory jogger.

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Original NASA ASRS Text

Title: SMA X ISSUED WRONG VECTOR HDG AFTER DEP HAD LTSS FROM SMA Y. SYS ERROR.

Narrative: I WAS WORKING SCK TWR, ALL POSITIONS COMBINED AT THE FLT DATA POS. I HAD 3 ACFT ON APCH WHEN THE SMA X REQUESTED A CLRNC TO TAXI AND PICK UP AN IFR FOR AN APCH AT SCK, THEN IFR TO FAT. AN SMA RPTED MISSED AT THE SAME TIME SMA X WAS MAKING HIS REQUEST. I TOLD THE SMA TO CONTACT DEP AND THEN ADVISED SMA X I HAD HIS CLRNC. I ISSUED THE CLRNC FOR THE SCK ARPT AND Told HIM TO EXPECT CLRNC FOR FAT ON THE DOWNWIND. IN ISSUING THE CLRNC I GAVE A WRONG INITIAL HDG OF 200 DEG INSTEAD OF 050 DEG. THE PLT READ IT BACK AND I MISSED IT ON THE READBACK AS I WAS TYPING IN THE ACFT NUMBER AND TYPE INTO THE ARTS SYS. SMA X TOOK OFF AND TURNED TO A HDG OF 200 WHICH BROUGHT HIM BACK OVER THE ARPT. SMA Y WAS CLBING OUT ON RWY HDG AND THEY WERE LESS THAN 500 FT ALT APART AND LESS THAN 1/2 MI. THEY WERE BOTH IMC. SMA X WAS TURNED AWAY BY THE APCH CTLR. ONE OF THE CONTRIBUTING FACTORS IS THAT WHEN LCL IS COMBINED AT GND, THE GND FREQ IS EXTREMELY WEAK. THIS PLUS THE DIVERSION OF COMPUTER ENTRIES AND LISTENING ONLY TO WHAT I WANTED TO HEAR COULD HAVE DEVELOPED INTO DISASTER. POSSIBLE SOLUTIONS: HAVE MAINT INCREASE GND CTL VOLUME, WRITE CLRNC ON BLANK STRIP EVEN WHEN WORKING ALONE AS MEMORY JOGGER.

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.