Narrative:

VFR night flight. I was trying to establish contact with approach for radar services, unsuccessfully. After completing checks, we began our descent. My copilot was distracted by a passenger. While he tended to the passenger, I decided to level off and try to contact TRACON for RA's. I inadvertently chose 7500 ft MSL to level off. This was an improper altitude for direction of flight of southwest. As I established contact with TRACON, ATC advised me of radar contact and opposite direction traffic, at our altitude, within a couple of mi. By this time the passenger were again seated and my copilot had returned his attention to our cockpit duties. As the traffic was pointed out I visually acquired the traffic and continued our descent. We passed within several hundred ft of the other VFR traffic. We were finishing up a 14 hour duty day. I believe that contributed to my inadvertently picking the wrong altitude. Receiving RA's sooner may have prevented the situation from arising. It was a particularly clear evening. This may have given us a false sense of security.

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Original NASA ASRS Text

Title: CAPT OF AN ATX SMT TURBOPROP LEVELED OFF AT AN INAPPROPRIATE ALT DURING A VFR DSCNT CAUSING AN NMAC WITH ANOTHER ACFT COMING FROM THE OPPOSITE DIRECTION. APCH CTLR ALERTED HIM TO THE ERROR AFTER THE CAPT CONTACTED APCH FOR RA'S.

Narrative: VFR NIGHT FLT. I WAS TRYING TO ESTABLISH CONTACT WITH APCH FOR RADAR SVCS, UNSUCCESSFULLY. AFTER COMPLETING CHKS, WE BEGAN OUR DSCNT. MY COPLT WAS DISTRACTED BY A PAX. WHILE HE TENDED TO THE PAX, I DECIDED TO LEVEL OFF AND TRY TO CONTACT TRACON FOR RA'S. I INADVERTENTLY CHOSE 7500 FT MSL TO LEVEL OFF. THIS WAS AN IMPROPER ALT FOR DIRECTION OF FLT OF SW. AS I ESTABLISHED CONTACT WITH TRACON, ATC ADVISED ME OF RADAR CONTACT AND OPPOSITE DIRECTION TFC, AT OUR ALT, WITHIN A COUPLE OF MI. BY THIS TIME THE PAX WERE AGAIN SEATED AND MY COPLT HAD RETURNED HIS ATTN TO OUR COCKPIT DUTIES. AS THE TFC WAS POINTED OUT I VISUALLY ACQUIRED THE TFC AND CONTINUED OUR DSCNT. WE PASSED WITHIN SEVERAL HUNDRED FT OF THE OTHER VFR TFC. WE WERE FINISHING UP A 14 HR DUTY DAY. I BELIEVE THAT CONTRIBUTED TO MY INADVERTENTLY PICKING THE WRONG ALT. RECEIVING RA'S SOONER MAY HAVE PREVENTED THE SIT FROM ARISING. IT WAS A PARTICULARLY CLR EVENING. THIS MAY HAVE GIVEN US A FALSE SENSE OF SECURITY.

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.