Report of radar antenna stopping and then started turning very slowly.

Attributes
ACN	396230
Time
Date	199803
Day	Wed
Local Time Of Day	1801 To 2400
Place
Locale Reference	atc facility : mci
State Reference	MO
Environment
Flight Conditions	VMC
Light	Night
Person 1
Affiliation	government : faa
Function	controller : approach
Qualification	controller : radar
Experience	controller radar : 13
ASRS Report	396230
Events
Anomaly	other anomaly other
Independent Detector	other controllera
Resolutory Action	none taken : detected after the fact
Consequence	Other
Supplementary
Primary Problem	Navigational Facility
Air Traffic Incident	other
Situations
ATC Facility	other physical facility

Narrative:

The radar antenna stopped and then started moving very, very slow. Approximately 8 aircraft in the kansas city area at the time. All departures and arrs stopped for about 10 mins. Cenrap (backup system) was brought up and we resumed operations with twice the standard separation. Airways facilities believe that both of the breakers blew at the radar site. The WX was good once again. I hope I am not here when this happens in bad WX. Trust me it will happen again. Callback conversation with reporter revealed the following information: reporter alleges there is a design flaw with the antenna system. Reporter stated the reason the antenna stopped was that the WX had been real cold and the heater to warm the antenna equipment failed. Reporter indicated there is no warning alarm when the heater fails. Reporter also alleged that the antenna failed recently and was caused by moisture in the cable affecting the antenna operations.

Original NASA ASRS Text

Title: RPT OF RADAR ANTENNA STOPPING AND THEN STARTED TURNING VERY SLOWLY.

Narrative: THE RADAR ANTENNA STOPPED AND THEN STARTED MOVING VERY, VERY SLOW. APPROX 8 ACFT IN THE KANSAS CITY AREA AT THE TIME. ALL DEPS AND ARRS STOPPED FOR ABOUT 10 MINS. CENRAP (BACKUP SYS) WAS BROUGHT UP AND WE RESUMED OPS WITH TWICE THE STANDARD SEPARATION. AIRWAYS FACILITIES BELIEVE THAT BOTH OF THE BREAKERS BLEW AT THE RADAR SITE. THE WX WAS GOOD ONCE AGAIN. I HOPE I AM NOT HERE WHEN THIS HAPPENS IN BAD WX. TRUST ME IT WILL HAPPEN AGAIN. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR ALLEGES THERE IS A DESIGN FLAW WITH THE ANTENNA SYS. RPTR STATED THE REASON THE ANTENNA STOPPED WAS THAT THE WX HAD BEEN REAL COLD AND THE HEATER TO WARM THE ANTENNA EQUIP FAILED. RPTR INDICATED THERE IS NO WARNING ALARM WHEN THE HEATER FAILS. RPTR ALSO ALLEGED THAT THE ANTENNA FAILED RECENTLY AND WAS CAUSED BY MOISTURE IN THE CABLE AFFECTING THE ANTENNA OPS.

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.