Air carrier X TCASII RA from ghost target.

Attributes
ACN	247008
Time
Date	199306
Day	Mon
Local Time Of Day	0001 To 0600
Place
Locale Reference	atc facility : ord
State Reference	IL
Altitude	msl bound lower : 6800 msl bound upper : 6800
Environment
Light	Dawn
Aircraft 1
Controlling Facilities	tracon : ord
Operator	common carrier : air carrier
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Flight Phase	descent : approach
Route In Use	enroute : on vectors
Flight Plan	IFR
Person 1
Affiliation	government : faa
Function	controller : approach
Qualification	controller : radar
Experience	controller radar : 10
ASRS Report	247008
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Events
Anomaly	altitude deviation : overshoot non adherence : clearance
Independent Detector	aircraft equipment other aircraft equipment : unspecified
Resolutory Action	none taken : detected after the fact
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

Air carrier X was cleared to 4000 ft. The pilot advised ATC he was responding to a TCASII RA and was climbing. There was no, repeat no, aircraft known or unknown within 4 mi in any direction. The pilot advised he showed traffic 200 ft below. There was a clearance deviation by the TCASII aircraft of at least 700 ft. Communication did not take place until after the TCASII maneuver.

Original NASA ASRS Text

Title: ACR X TCASII RA FROM GHOST TARGET.

Narrative: ACR X WAS CLRED TO 4000 FT. THE PLT ADVISED ATC HE WAS RESPONDING TO A TCASII RA AND WAS CLBING. THERE WAS NO, REPEAT NO, ACFT KNOWN OR UNKNOWN WITHIN 4 MI IN ANY DIRECTION. THE PLT ADVISED HE SHOWED TFC 200 FT BELOW. THERE WAS A CLRNC DEV BY THE TCASII ACFT OF AT LEAST 700 FT. COM DID NOT TAKE PLACE UNTIL AFTER THE TCASII MANEUVER.

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.