Narrative:

Following normal VFR pre-establish departure, I took off from north las vegas airport and climb to 4000 ft right turn direct to B of a building (VFR check pt). At B of a building the departure call for left turn direct las vegas mc carran airport runway 19 E25 threshold. Clearing my left turn I saw a white piper light white twin, navajo or cheyenne, just next to me. 'Xyz' I could see the number as he was parked next to me on the ramp and that was the approximately distance he was at. I knew from his ATC communication that he was suppose to follow me. I took smooth evasive action to the right and after in-flight collision wasn't a concern anymore I call las vegas approach and ask them 'las approach wasn't xyz suppose to follow me and maintain visual separation?' 'that's affirmative why?' (me) 'he almost touched my wing.' (las) 'xyz don't pass this 402 you are suppose to maintain visual separation and follow him.' (xyz) 'yes sir I had the traffic in front of him in sight and thought it was the traffic I was supposed to follow.' (las) 'xyz make a 360 degree left turn and remain behind aircraft.' this is a mistake that can happen to everybody, specially when you think you have traffic in sight and it's not the case. To prevent that: make sure the traffic you see is the one the controller is speaking about. Confirm position, heading, altitude, maneuver of the traffic that you see with ATC. Always look outside and scan for other traffic would probably have prevented this near air miss. Be aware at all times with ATC communications of the pilots in front of you and the ones behind specially in VFR operation like ours, flying the same departures, arrival rtes and en route over the grand canyon. If you made a mistake be humble and don't find excuses.

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Original NASA ASRS Text

Title: ATX COMMUTER OFF VGT VFR CLBING TO 4000 FT. L TURN TO PROCEED DIRECT LAS, SAW TFC ON THE L WITHIN 10 FT VERT AND 50 FT HORIZ, CLOSE ENOUGH TO READ THE ACFT NUMBER EASILY. ACFT HAD BEEN PARKED NEXT TO RPTR AT VGT. CLRNC HAD BEEN TO FOLLOW ATX BUT THE PIPER TWIN NAVAJO HAD IDENTED ANOTHER ACFT AS HIS TFC. DEP CTLR HAD HIM MAKE A 360 DEG TURN AND FOLLOW THE RPTR.

Narrative: FOLLOWING NORMAL VFR PRE-ESTABLISH DEP, I TOOK OFF FROM NORTH LAS VEGAS ARPT AND CLB TO 4000 FT R TURN DIRECT TO B OF A BUILDING (VFR CHK PT). AT B OF A BUILDING THE DEP CALL FOR L TURN DIRECT LAS VEGAS MC CARRAN ARPT RWY 19 E25 THRESHOLD. CLRING MY L TURN I SAW A WHITE PIPER LIGHT WHITE TWIN, NAVAJO OR CHEYENNE, JUST NEXT TO ME. 'XYZ' I COULD SEE THE NUMBER AS HE WAS PARKED NEXT TO ME ON THE RAMP AND THAT WAS THE APPROX DISTANCE HE WAS AT. I KNEW FROM HIS ATC COM THAT HE WAS SUPPOSE TO FOLLOW ME. I TOOK SMOOTH EVASIVE ACTION TO THE R AND AFTER INFLT COLLISION WASN'T A CONCERN ANYMORE I CALL LAS VEGAS APCH AND ASK THEM 'LAS APCH WASN'T XYZ SUPPOSE TO FOLLOW ME AND MAINTAIN VISUAL SEPARATION?' 'THAT'S AFFIRMATIVE WHY?' (ME) 'HE ALMOST TOUCHED MY WING.' (LAS) 'XYZ DON'T PASS THIS 402 YOU ARE SUPPOSE TO MAINTAIN VISUAL SEPARATION AND FOLLOW HIM.' (XYZ) 'YES SIR I HAD THE TFC IN FRONT OF HIM IN SIGHT AND THOUGHT IT WAS THE TFC I WAS SUPPOSED TO FOLLOW.' (LAS) 'XYZ MAKE A 360 DEG L TURN AND REMAIN BEHIND ACFT.' THIS IS A MISTAKE THAT CAN HAPPEN TO EVERYBODY, SPECIALLY WHEN YOU THINK YOU HAVE TFC IN SIGHT AND IT'S NOT THE CASE. TO PREVENT THAT: MAKE SURE THE TFC YOU SEE IS THE ONE THE CTLR IS SPEAKING ABOUT. CONFIRM POS, HDG, ALT, MANEUVER OF THE TFC THAT YOU SEE WITH ATC. ALWAYS LOOK OUTSIDE AND SCAN FOR OTHER TFC WOULD PROBABLY HAVE PREVENTED THIS NEAR AIR MISS. BE AWARE AT ALL TIMES WITH ATC COMS OF THE PLTS IN FRONT OF YOU AND THE ONES BEHIND SPECIALLY IN VFR OP LIKE OURS, FLYING THE SAME DEPS, ARR RTES AND ENRTE OVER THE GRAND CANYON. IF YOU MADE A MISTAKE BE HUMBLE AND DON'T FIND EXCUSES.

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.