Air carrier X TCASII RA with VFR aircraft in TCA. Standard separation existed. Evasive action taken.

Attributes
ACN	247009
Time
Date	199306
Day	Tue
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : ord
State Reference	IL
Altitude	msl bound lower : 6200 msl bound upper : 7000
Environment
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : ord
Operator	common carrier : air carrier
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Flight Phase	descent : approach
Flight Plan	IFR
Aircraft 2
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Flight Phase	cruise other
Route In Use	enroute : direct
Flight Plan	VFR
Person 1
Affiliation	government : faa
Function	controller : approach
Qualification	controller : radar
Experience	controller radar : 7
ASRS Report	247009
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Events
Anomaly	altitude deviation : excursion from assigned altitude conflict : airborne less severe non adherence : clearance
Independent Detector	aircraft equipment other aircraft equipment : unspecified
Resolutory Action	flight crew : took evasive action
Consequence	Other
Miss Distance	vertical : 800
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	other

Narrative:

Air carrier X advised the controller of an RA and advised that he was climbing. There was a VFR aircraft Y in area that showed 6200 ft. There was a clearance deviation by the TCASII aircraft of at least 300 ft. This appears to be a non valid RA because the VFR separation required by ATC is 500 ft vertical.

Original NASA ASRS Text

Title: ACR X TCASII RA WITH VFR ACFT IN TCA. STANDARD SEPARATION EXISTED. EVASIVE ACTION TAKEN.

Narrative: ACR X ADVISED THE CTLR OF AN RA AND ADVISED THAT HE WAS CLBING. THERE WAS A VFR ACFT Y IN AREA THAT SHOWED 6200 FT. THERE WAS A CLRNC DEV BY THE TCASII ACFT OF AT LEAST 300 FT. THIS APPEARS TO BE A NON VALID RA BECAUSE THE VFR SEPARATION REQUIRED BY ATC IS 500 FT VERT.

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.