Controller report of air carrier query reference traffic shown on TCASII. False target.

Attributes
ACN	214847
Time
Date	199206
Day	Wed
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : roa
State Reference	VA
Altitude	msl bound lower : 3200 msl bound upper : 3800
Environment
Flight Conditions	Marginal
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : roa
Operator	common carrier : air taxi
Make Model Name	Small Transport, Low Wing, 2 Turboprop Eng
Flight Phase	descent : approach
Flight Plan	VFR
Person 1
Affiliation	company : air taxi
Function	controller : approach
Qualification	controller : radar
ASRS Report	214847
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Events
Anomaly	other anomaly other
Independent Detector	other flight crewa
Resolutory Action	other
Consequence	Other
Supplementary
Primary Problem	Aircraft
Air Traffic Incident	other

Narrative:

Aircraft (an small transport) asked me (east radar controller) if I saw the traffic at 2.3 mi ahead at 3200 ft with code XXXX. I observed no traffic in the reported position, but that traffic was observed at the pilot's 6 O'clock position at FL180, 20 mi. Erroneous TCASII assumed.

Original NASA ASRS Text

Title: CTLR RPT OF ACR QUERY REF TFC SHOWN ON TCASII. FALSE TARGET.

Narrative: ACFT (AN SMT) ASKED ME (E RADAR CTLR) IF I SAW THE TFC AT 2.3 MI AHEAD AT 3200 FT WITH CODE XXXX. I OBSERVED NO TFC IN THE RPTED POS, BUT THAT TFC WAS OBSERVED AT THE PLT'S 6 O'CLOCK POS AT FL180, 20 MI. ERRONEOUS TCASII ASSUMED.

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.