Medium large transport on approach has TCASII RA. Responds with climb. Approach controller says no o...

Attributes
ACN	213056
Time
Date	199206
Day	Tue
Local Time Of Day	1801 To 2400
Place
Locale Reference	airport : ord
State Reference	IL
Altitude	msl bound lower : 5000 msl bound upper : 5200
Environment
Flight Conditions	IMC
Light	Dusk
Aircraft 1
Controlling Facilities	tracon : ord
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Flight Phase	descent : approach
Route In Use	enroute : on vectors
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 200 flight time total : 10000 flight time type : 5000
ASRS Report	213056
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp pilot : commercial pilot : instrument
Events
Anomaly	altitude deviation : excursion from assigned altitude non adherence : clearance other anomaly other
Independent Detector	other flight crewa
Resolutory Action	flight crew : returned to intended course or assigned course none taken : unable
Consequence	faa : reviewed incident with flight crew
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	other

Narrative:

While approaching ord there seemed to be a great deal of confusion during a reconfign of runways. As we were turned on the 22R ILS we commented that we saw traffic close to us 1-2 mi but were informed that no one was close to us. Some few seconds later, got a TCASII RA to 'climb' -- which we did -- to about 4200 MSL. Controller said 'there is no one near you -- maintain 5000. We encountered a wake that rolled us through 15 degree shortly after the RA. I cannot account for the wake other than the TCASII 'target' that was not seen on the ord radar. Flight forward visibility was about 1 mi.

Original NASA ASRS Text

Title: MLG ON APCH HAS TCASII RA. RESPONDS WITH CLB. APCH CTLR SAYS NO ONE NEAR YOU.

Narrative: WHILE APCHING ORD THERE SEEMED TO BE A GREAT DEAL OF CONFUSION DURING A RECONFIGN OF RWYS. AS WE WERE TURNED ON THE 22R ILS WE COMMENTED THAT WE SAW TFC CLOSE TO US 1-2 MI BUT WERE INFORMED THAT NO ONE WAS CLOSE TO US. SOME FEW SECONDS LATER, GOT A TCASII RA TO 'CLB' -- WHICH WE DID -- TO ABOUT 4200 MSL. CTLR SAID 'THERE IS NO ONE NEAR YOU -- MAINTAIN 5000. WE ENCOUNTERED A WAKE THAT ROLLED US THROUGH 15 DEG SHORTLY AFTER THE RA. I CANNOT ACCOUNT FOR THE WAKE OTHER THAN THE TCASII 'TARGET' THAT WAS NOT SEEN ON THE ORD RADAR. FLT FORWARD VISIBILITY WAS ABOUT 1 MI.

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.

Medium large transport on approach has TCASII RA. Responds with climb. Approach controller says no one near you.