ATC equipment problem radar ASR-9 mode south failed.

Attributes
ACN	311766
Time
Date	199507
Day	Fri
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : iad
State Reference	VA
Environment
Flight Conditions	VMC
Light	Daylight
Person 1
Affiliation	government : faa
Function	other personnel other
Qualification	controller : radar
Experience	controller non radar : 2 controller radar : 11
ASRS Report	311766
Events
Anomaly	other anomaly other
Resolutory Action	other
Consequence	faa : investigated
Supplementary
Primary Problem	Navigational Facility
Air Traffic Incident	other
Situations
Navigational Aid	Unspecified

Narrative:

ASR-9, mode south: we have been experiencing 'coasting' since implementation of mode south a few months ago. This time data tags dropped off, lost all transponder targets. Brought up cenrap 'plus' -- lost all targets -- went to cenrap. Problem is supposedly under investigation, but ATC is out of the loop. Callback conversation with reporter revealed the following information: reporter stated the incident was investigated by FAA maintenance and was found to be caused by the failure of 2 modum's in the mode south system. These were replaced and the reporter knowledge there has not been another ASR-9 mode south failure.

Original NASA ASRS Text

Title: ATC EQUIP PROB RADAR ASR-9 MODE S FAILED.

Narrative: ASR-9, MODE S: WE HAVE BEEN EXPERIENCING 'COASTING' SINCE IMPLEMENTATION OF MODE S A FEW MONTHS AGO. THIS TIME DATA TAGS DROPPED OFF, LOST ALL XPONDER TARGETS. BROUGHT UP CENRAP 'PLUS' -- LOST ALL TARGETS -- WENT TO CENRAP. PROB IS SUPPOSEDLY UNDER INVESTIGATION, BUT ATC IS OUT OF THE LOOP. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR STATED THE INCIDENT WAS INVESTIGATED BY FAA MAINT AND WAS FOUND TO BE CAUSED BY THE FAILURE OF 2 MODUM'S IN THE MODE S SYS. THESE WERE REPLACED AND THE RPTR KNOWLEDGE THERE HAS NOT BEEN ANOTHER ASR-9 MODE S FAILURE.

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.