Aircraft on final approach are showing on radar as south of course.

Attributes
ACN	225921
Time
Date	199211
Day	Thu
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : ord
State Reference	IL
Environment
Flight Conditions	Mixed
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : ord
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Flight Phase	descent : approach
Route In Use	arrival other
Flight Plan	IFR
Person 1
Affiliation	government : faa
Function	controller : approach
Qualification	controller : radar
ASRS Report	225921
Events
Anomaly	other anomaly other
Independent Detector	other controllera
Resolutory Action	none taken : unable
Consequence	Other
Supplementary
Primary Problem	Navigational Facility
Air Traffic Incident	other
Situations
ATC Facility	other physical facility
Navigational Aid	Unspecified

Narrative:

I was working east arrival to runway 27R at ord. My traffic consistently showed south of the final and near the runway 27L final. I asked pilots on numerous occasions to verify being on the localizer. There was parallel traffic. I feel we should not be required to work traffic under these conditions. It creates undue stress and workload on the controllers. My suggestions for correcting this problem are as follows: 1) until the ASR-9 can be used for our simultaneous approachs, we should not run this confign (runway 27 simultaneous approachs). 2) only runway 27 stagger (parallel) ILS approachs with the ASR-9. (Flow traffic to accommodate.) in addition to the targets/map problem, the coasting was excessive. At times, data blocks dropped completely from the targets. This is unsafe. Solutions are: 1) not run the ASR-7 unless needed as an emergency back-up. 2) don't use the ASR-7 to run simultaneous approachs, so we can run more traffic with an older system, which has major coasting problems and does not show the targets on centerline on the map! Callback conversation with reporter revealed the following information: reporter claims that they found a problem with video map alignment. After they realigned it, aircraft were showing on course. 2 ucr's were filed on the same day on this problem. No response received from facility as of this date.

Original NASA ASRS Text

Title: ACFT ON FINAL APCH ARE SHOWING ON RADAR AS S OF COURSE.

Narrative: I WAS WORKING E ARR TO RWY 27R AT ORD. MY TFC CONSISTENTLY SHOWED S OF THE FINAL AND NEAR THE RWY 27L FINAL. I ASKED PLTS ON NUMEROUS OCCASIONS TO VERIFY BEING ON THE LOC. THERE WAS PARALLEL TFC. I FEEL WE SHOULD NOT BE REQUIRED TO WORK TFC UNDER THESE CONDITIONS. IT CREATES UNDUE STRESS AND WORKLOAD ON THE CTLRS. MY SUGGESTIONS FOR CORRECTING THIS PROBLEM ARE AS FOLLOWS: 1) UNTIL THE ASR-9 CAN BE USED FOR OUR SIMULTANEOUS APCHS, WE SHOULD NOT RUN THIS CONFIGN (RWY 27 SIMULTANEOUS APCHS). 2) ONLY RWY 27 STAGGER (PARALLEL) ILS APCHS WITH THE ASR-9. (FLOW TFC TO ACCOMMODATE.) IN ADDITION TO THE TARGETS/MAP PROBLEM, THE COASTING WAS EXCESSIVE. AT TIMES, DATA BLOCKS DROPPED COMPLETELY FROM THE TARGETS. THIS IS UNSAFE. SOLUTIONS ARE: 1) NOT RUN THE ASR-7 UNLESS NEEDED AS AN EMER BACK-UP. 2) DON'T USE THE ASR-7 TO RUN SIMULTANEOUS APCHS, SO WE CAN RUN MORE TFC WITH AN OLDER SYS, WHICH HAS MAJOR COASTING PROBLEMS AND DOES NOT SHOW THE TARGETS ON CTRLINE ON THE MAP! CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR CLAIMS THAT THEY FOUND A PROBLEM WITH VIDEO MAP ALIGNMENT. AFTER THEY REALIGNED IT, ACFT WERE SHOWING ON COURSE. 2 UCR'S WERE FILED ON THE SAME DAY ON THIS PROBLEM. NO RESPONSE RECEIVED FROM FACILITY AS OF THIS DATE.

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.