Narrative:

BE35 descending from 9000-5000 ft sebound V23. C210 level at 6000 ft, nwbound V23 in handoff status from another sector. This aircraft was in 'nats' status on my scope. ARTS IIIE does not display whether aircraft is VFR or IFR under these conditions. This is a typical scenario for this sector however 99.99% of these aircraft that go 'nats' are VFR at 4500 ft or below. The cessna was about to enter my airspace without a handoff. I called the other sector and advised them the cessna was in 'nats' status and that he was approved to enter (assuming that this aircraft was VFR). The bonanza was in handoff to this controller. The other controller answered with 'roger.' after the aircraft passed each other the computer 'saw' the cessna and gave me a firm data block. The other controller accepted the handoff on the bonanza. The bonanza pilot told me that he had seen the cessna go by.

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Original NASA ASRS Text

Title: SCT CTLR ASSUMES 'NATS (NON-ARTS TRACK STATUS)' ON ACFT DATA TAG IS A VFR ACFT, WHEN ACTUALLY IFR, AND IS INVOLVED IN OPERROR WITH ANOTHER OPPOSITE DIRECTION IFR ACFT.

Narrative: BE35 DSNDING FROM 9000-5000 FT SEBOUND V23. C210 LEVEL AT 6000 FT, NWBOUND V23 IN HDOF STATUS FROM ANOTHER SECTOR. THIS ACFT WAS IN 'NATS' STATUS ON MY SCOPE. ARTS IIIE DOES NOT DISPLAY WHETHER ACFT IS VFR OR IFR UNDER THESE CONDITIONS. THIS IS A TYPICAL SCENARIO FOR THIS SECTOR HOWEVER 99.99% OF THESE ACFT THAT GO 'NATS' ARE VFR AT 4500 FT OR BELOW. THE CESSNA WAS ABOUT TO ENTER MY AIRSPACE WITHOUT A HDOF. I CALLED THE OTHER SECTOR AND ADVISED THEM THE CESSNA WAS IN 'NATS' STATUS AND THAT HE WAS APPROVED TO ENTER (ASSUMING THAT THIS ACFT WAS VFR). THE BONANZA WAS IN HDOF TO THIS CTLR. THE OTHER CTLR ANSWERED WITH 'ROGER.' AFTER THE ACFT PASSED EACH OTHER THE COMPUTER 'SAW' THE CESSNA AND GAVE ME A FIRM DATA BLOCK. THE OTHER CTLR ACCEPTED THE HDOF ON THE BONANZA. THE BONANZA PLT TOLD ME THAT HE HAD SEEN THE CESSNA GO BY.

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.