Narrative:

We were flying an light transport on a cargo flight. I was the PNF (captain). It had become very foggy at slc that evening. Apparently runway 34L was in the clear. Runway 34R was in the fog. The visibility reported to us was 3/8 mi at time of takeoff. In my opinion it was considerably lower. As we approached runway 34R I called the tower ready for takeoff. Tower called us back and cleared us for takeoff. We completed the runway items portion of the before takeoff checklist and turning onto 34R. Just as we attempted to line up with the runway I noticed a white light peering out of the mist. The white light was moving toward us. My copilot (the PF) turned the aircraft left so as to miss the other aircraft. The other aircraft came into view, a commuter mdt. We reported to the tower that we were unable to takeoff with an mdt in the way. The tower directed us off the runway. We exited the runway to the left (west) side. The controller apologized and told us we would be next for takeoff. We never heard the controller put the light transport into position and hold. One idea is that the light transport was on the other tower frequency. In low visibility situations I make sure everything is correct before taxiing for takeoff. I was not speeding. Taking the runway under these conditions it would not have been prudent to go fast through the checklist and taxiing onto the runway. My heads-up copilot kept us from possibly hitting the commuter mdt. One last thing, the airliners were lined up on 32 for takeoff. I came up from the GA ramp and entered the runway from the east side on intersection K1.

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Original NASA ASRS Text

Title: CLOSE PROX ON THE GND AT SLC. 2 ACFT CLRED ONTO THE SAME RWY FROM OPPOSITE SIDES IN THE FOG AT NIGHT.

Narrative: WE WERE FLYING AN LTT ON A CARGO FLT. I WAS THE PNF (CAPT). IT HAD BECOME VERY FOGGY AT SLC THAT EVENING. APPARENTLY RWY 34L WAS IN THE CLR. RWY 34R WAS IN THE FOG. THE VISIBILITY RPTED TO US WAS 3/8 MI AT TIME OF TKOF. IN MY OPINION IT WAS CONSIDERABLY LOWER. AS WE APCHED RWY 34R I CALLED THE TWR READY FOR TKOF. TWR CALLED US BACK AND CLRED US FOR TKOF. WE COMPLETED THE RWY ITEMS PORTION OF THE BEFORE TKOF CHKLIST AND TURNING ONTO 34R. JUST AS WE ATTEMPTED TO LINE UP WITH THE RWY I NOTICED A WHITE LIGHT PEERING OUT OF THE MIST. THE WHITE LIGHT WAS MOVING TOWARD US. MY COPLT (THE PF) TURNED THE ACFT L SO AS TO MISS THE OTHER ACFT. THE OTHER ACFT CAME INTO VIEW, A COMMUTER MDT. WE RPTED TO THE TWR THAT WE WERE UNABLE TO TKOF WITH AN MDT IN THE WAY. THE TWR DIRECTED US OFF THE RWY. WE EXITED THE RWY TO THE L (W) SIDE. THE CTLR APOLOGIZED AND TOLD US WE WOULD BE NEXT FOR TKOF. WE NEVER HEARD THE CTLR PUT THE LTT INTO POS AND HOLD. ONE IDEA IS THAT THE LTT WAS ON THE OTHER TWR FREQ. IN LOW VISIBILITY SITUATIONS I MAKE SURE EVERYTHING IS CORRECT BEFORE TAXIING FOR TKOF. I WAS NOT SPDING. TAKING THE RWY UNDER THESE CONDITIONS IT WOULD NOT HAVE BEEN PRUDENT TO GO FAST THROUGH THE CHKLIST AND TAXIING ONTO THE RWY. MY HEADS-UP COPLT KEPT US FROM POSSIBLY HITTING THE COMMUTER MDT. ONE LAST THING, THE AIRLINERS WERE LINED UP ON 32 FOR TKOF. I CAME UP FROM THE GA RAMP AND ENTERED THE RWY FROM THE E SIDE ON INTXN K1.

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.