Narrative:

It was XA20 pm, jan/wed/99. I was flying for a local company. I was 7 mi northwest of dekalb-peachtree airport following highway 400 (I-19) sbound, on the east side of the highway. I listened to the current ATIS-oscar (which was missing the current altimeter setting). They were using split frequencys, traffic inbound from the west contact tower 127.2, traffic inbound from the east contact tower on 120.9. I contacted tower on 127.2 and they cleared me to transition at 2900 ft MSL. I proceeded to transition sbound, about 3 mi into their airspace, they advised me of a king air departing on a westerly heading at 11 O'clock position and 2 mi which I saw, and other traffic inbound for landing a twin cessna at 12:30 O'clock position and 1 mi (the visibility was very poor to the west due to the sun setting) I did not see the traffic. The twin cessna was talking to tower on 120.9, according to the ATIS he should have been on 127.2, I continued to look for traffic. Tower then gave me a traffic alert, 'aircraft X traffic in your immediate vicinity at your 3 O'clock position.' I then lifted my right wing in a climbing left turn to get a better look out the right side of the aircraft and saw the twin cessna as he was in a descending left turn at 50 ft below me. Just as the twin cessna flew under me tower advised me that he had me in sight.

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Original NASA ASRS Text

Title: PLT IN SMA ACFT W OF PDK ARPT HAS NMAC WITH TWIN CESSNA INBOUND FROM THE W LNDG AT PDK.

Narrative: IT WAS XA20 PM, JAN/WED/99. I WAS FLYING FOR A LCL COMPANY. I WAS 7 MI NW OF DEKALB-PEACHTREE ARPT FOLLOWING HWY 400 (I-19) SBOUND, ON THE E SIDE OF THE HWY. I LISTENED TO THE CURRENT ATIS-OSCAR (WHICH WAS MISSING THE CURRENT ALTIMETER SETTING). THEY WERE USING SPLIT FREQS, TFC INBOUND FROM THE W CONTACT TWR 127.2, TFC INBOUND FROM THE E CONTACT TWR ON 120.9. I CONTACTED TWR ON 127.2 AND THEY CLRED ME TO TRANSITION AT 2900 FT MSL. I PROCEEDED TO TRANSITION SBOUND, ABOUT 3 MI INTO THEIR AIRSPACE, THEY ADVISED ME OF A KING AIR DEPARTING ON A WESTERLY HEADING AT 11 O'CLOCK POS AND 2 MI WHICH I SAW, AND OTHER TFC INBOUND FOR LNDG A TWIN CESSNA AT 12:30 O'CLOCK POS AND 1 MI (THE VISIBILITY WAS VERY POOR TO THE W DUE TO THE SUN SETTING) I DID NOT SEE THE TFC. THE TWIN CESSNA WAS TALKING TO TWR ON 120.9, ACCORDING TO THE ATIS HE SHOULD HAVE BEEN ON 127.2, I CONTINUED TO LOOK FOR TFC. TWR THEN GAVE ME A TFC ALERT, 'ACFT X TFC IN YOUR IMMEDIATE VICINITY AT YOUR 3 O'CLOCK POS.' I THEN LIFTED MY R WING IN A CLBING L TURN TO GET A BETTER LOOK OUT THE R SIDE OF THE ACFT AND SAW THE TWIN CESSNA AS HE WAS IN A DSNDING L TURN AT 50 FT BELOW ME. JUST AS THE TWIN CESSNA FLEW UNDER ME TWR ADVISED ME THAT HE HAD ME IN SIGHT.

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.