ATC equipment problem radar failure. Air carrier X had less than standard separation from cpr Y. Sys...

Attributes
ACN	162109
Time
Date	199011
Day	Wed
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : day
State Reference	OH
Altitude	msl bound lower : 7800 msl bound upper : 8000
Environment
Flight Conditions	VMC
Light	Dusk
Aircraft 1
Controlling Facilities	tracon : day
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Navigation In Use	Other
Flight Phase	cruise other
Route In Use	enroute : on vectors
Flight Plan	IFR
Aircraft 2
Operator	general aviation : corporate
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Flight Phase	cruise other descent other
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 : 50 flight time total : 12000 flight time type : 50
ASRS Report	162109
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp
Experience	flight time last 90 days : 180 flight time total : 10000 flight time type : 2000
ASRS Report	162570
Events
Anomaly	conflict : airborne less severe non adherence : published procedure non adherence : required legal separation other anomaly other
Independent Detector	other flight crewa
Resolutory Action	flight crew : took evasive action
Consequence	Other
Miss Distance	horizontal : 4000 vertical : 200
Supplementary
Primary Problem	Navigational Facility
Air Traffic Incident	Operational Error

Narrative:

Air carrier X was on approach into dayton airport at 8000' when approach control said they were experiencing radar problems. We were heading southbound and given a left turn to 050 degree. On that heading, we were given a further left turn ot a heading of 150 degree. Passing through 240 degree heading we saw a cpr Y jet at our altitude heading right to left (approximately 3/4 of a mi in front of us). We rolled out on our present heading. Cpr Y also saw us and made a descent. We passed above and behind the jet. Approach control apologized to all aircraft involved in the area and said they had experienced a complete radar failure for about 5 mins. Radar came back and rest of approach was normal. Supplemental information from acn 162570. It might have been helpful if approach control had made it clear right away that they had a complete radar outage. In VMC everyone would have been extra vigilant. In IMC conditions there would have been the possibility of a midair in this particular incident.

Original NASA ASRS Text

Title: ATC EQUIPMENT PROBLEM RADAR FAILURE. ACR X HAD LESS THAN STANDARD SEPARATION FROM CPR Y. SYSTEM ERROR.

Narrative: ACR X WAS ON APCH INTO DAYTON ARPT AT 8000' WHEN APCH CTL SAID THEY WERE EXPERIENCING RADAR PROBS. WE WERE HDG SBND AND GIVEN A L TURN TO 050 DEG. ON THAT HDG, WE WERE GIVEN A FURTHER L TURN OT A HDG OF 150 DEG. PASSING THROUGH 240 DEG HDG WE SAW A CPR Y JET AT OUR ALT HDG R TO L (APPROX 3/4 OF A MI IN FRONT OF US). WE ROLLED OUT ON OUR PRESENT HDG. CPR Y ALSO SAW US AND MADE A DSNT. WE PASSED ABOVE AND BEHIND THE JET. APCH CTL APOLOGIZED TO ALL ACFT INVOLVED IN THE AREA AND SAID THEY HAD EXPERIENCED A COMPLETE RADAR FAILURE FOR ABOUT 5 MINS. RADAR CAME BACK AND REST OF APCH WAS NORMAL. SUPPLEMENTAL INFO FROM ACN 162570. IT MIGHT HAVE BEEN HELPFUL IF APCH CTL HAD MADE IT CLR R AWAY THAT THEY HAD A COMPLETE RADAR OUTAGE. IN VMC EVERYONE WOULD HAVE BEEN EXTRA VIGILANT. IN IMC CONDITIONS THERE WOULD HAVE BEEN THE POSSIBILITY OF A MIDAIR IN THIS PARTICULAR INCIDENT.

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.

ATC equipment problem radar failure. Air carrier X had less than standard separation from cpr Y. System error.