ATC radar equipment problem radar ARTS mode C unreliable.

Attributes
ACN	250973
Time
Date	199309
Day	Fri
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : lft
State Reference	LA
Person 1
Affiliation	government : faa
Function	controller : approach
Qualification	controller : radar
Experience	controller radar : 7
ASRS Report	250973
Person 2
Affiliation	government : faa
Function	controller : approach
Qualification	controller : radar
Experience	controller military : 4 controller radar : 11
ASRS Report	250974
Events
Anomaly	other anomaly other
Independent Detector	other controllera
Resolutory Action	none taken : unable
Consequence	faa : investigated
Supplementary
Primary Problem	Navigational Facility
Air Traffic Incident	other
Situations
Navigational Aid	Unspecified

Narrative:

The mode C at lft has been showing 'XXX' very frequently instead of an altitude readout. This situation has been occurring for about 6 months. Within the last 2 weeks the mode C had been erroneous as well as the 'XXX's.' the erroneous altitude reports or no readout at all has caused several sits that could have resulted in a near miss or a collision. No one seems to know why the readouts are a problem. It has yet to be determined whether the problem lies in the hardware or software. The southwest regional office has become aware of the problem and ordered the facility to inhibit the mode C readout. This situation is also unacceptable. The workload has increased threefold. More time is spent coordinating than viewing the traffic. This situation needs to be corrected as soon as possible. Callback conversation with reporter revealed the following information: planning and procedures specialist was contacted about mode C problem. He stated the mode C was taken OTS before a facility evaluation. ARTS mode C was returned to service in 30 days. Reason for mode C unreliability was not determined. FAA maintenance changed some components and the mode C worked correctly.

Original NASA ASRS Text

Title: ATC RADAR EQUIP PROB RADAR ARTS MODE C UNRELIABLE.

Narrative: THE MODE C AT LFT HAS BEEN SHOWING 'XXX' VERY FREQUENTLY INSTEAD OF AN ALT READOUT. THIS SIT HAS BEEN OCCURRING FOR ABOUT 6 MONTHS. WITHIN THE LAST 2 WKS THE MODE C HAD BEEN ERRONEOUS AS WELL AS THE 'XXX'S.' THE ERRONEOUS ALT RPTS OR NO READOUT AT ALL HAS CAUSED SEVERAL SITS THAT COULD HAVE RESULTED IN A NEAR MISS OR A COLLISION. NO ONE SEEMS TO KNOW WHY THE READOUTS ARE A PROB. IT HAS YET TO BE DETERMINED WHETHER THE PROB LIES IN THE HARDWARE OR SOFTWARE. THE SW REGIONAL OFFICE HAS BECOME AWARE OF THE PROB AND ORDERED THE FACILITY TO INHIBIT THE MODE C READOUT. THIS SIT IS ALSO UNACCEPTABLE. THE WORKLOAD HAS INCREASED THREEFOLD. MORE TIME IS SPENT COORDINATING THAN VIEWING THE TFC. THIS SIT NEEDS TO BE CORRECTED ASAP. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: PLANNING AND PROCS SPECIALIST WAS CONTACTED ABOUT MODE C PROB. HE STATED THE MODE C WAS TAKEN OTS BEFORE A FACILITY EVALUATION. ARTS MODE C WAS RETURNED TO SVC IN 30 DAYS. REASON FOR MODE C UNRELIABILITY WAS NOT DETERMINED. FAA MAINT CHANGED SOME COMPONENTS AND THE MODE C WORKED CORRECTLY.

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.