Air carrier X same assigned altitude as air carrier Y received TCASII TA RA evasive action descend had less than standard separation with air carrier Y. System error.

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Attributes
ACN	214997
Time
Date	199207
Day	Wed
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : spr
State Reference	FO
Altitude	msl bound lower : 31000 msl bound upper : 31000
Environment
Flight Conditions	Mixed
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : lsag
Operator	common carrier : air carrier
Make Model Name	Widebody, Low Wing, 4 Turbojet Eng
Flight Phase	cruise other
Route In Use	enroute : on vectors
Flight Plan	IFR
Aircraft 2
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Flight Phase	cruise other
Route In Use	enroute : direct
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 200 flight time total : 18000 flight time type : 2000
ASRS Report	214997
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp
Events
Anomaly	altitude deviation : excursion from assigned altitude conflict : airborne less severe non adherence : required legal separation non adherence : clearance non adherence : published procedure
Independent Detector	aircraft equipment other aircraft equipment : unspecified
Resolutory Action	controller : issued new clearance flight crew : took evasive action
Consequence	Other
Miss Distance	horizontal : 12000 vertical : 1000
Supplementary
Primary Problem	ATC Human Performance
Air Traffic Incident	Operational Error

Narrative:

Air carrier X was assigned heading 305 degrees by geneva control for approximately 5 mins when TCASII signal 'traffic' was sounded. TCASII indicated traffic converging (same altitude) left to right, approximately 8-9 mi. Call to geneva control was made to inquire if they had traffic at our altitude. TCASII directed 'descend.' I advised copilot to descend while waiting for response from controller. Control said 'roger, turn right 30 degrees.' since target was going right to left, direction of turn was being challenged when air carrier Y was sighted above us at 1-2 O'clock. Returned to 31000 after clear of aircraft and advised controller. He acknowledged and advised new clearance direct dijon VOR. Crossing aircraft was an air carrier Y, medium large transport who made an inquiry to geneva control about our altitude. A factor that may have caused incident was controller being preoccupied with another aircraft who was trying to get a new airway clearance.

Original NASA ASRS Text

Title: ACR X SAME ASSIGNED ALT AS ACR Y RECEIVED TCASII TA RA EVASIVE ACTION DSND HAD LTSS WITH ACR Y. SYS ERROR.

Narrative: ACR X WAS ASSIGNED HDG 305 DEGS BY GENEVA CTL FOR APPROX 5 MINS WHEN TCASII SIGNAL 'TFC' WAS SOUNDED. TCASII INDICATED TFC CONVERGING (SAME ALT) L TO R, APPROX 8-9 MI. CALL TO GENEVA CTL WAS MADE TO INQUIRE IF THEY HAD TFC AT OUR ALT. TCASII DIRECTED 'DSND.' I ADVISED COPLT TO DSND WHILE WAITING FOR RESPONSE FROM CTLR. CTL SAID 'ROGER, TURN R 30 DEGS.' SINCE TARGET WAS GOING R TO L, DIRECTION OF TURN WAS BEING CHALLENGED WHEN ACR Y WAS SIGHTED ABOVE US AT 1-2 O'CLOCK. RETURNED TO 31000 AFTER CLR OF ACFT AND ADVISED CTLR. HE ACKNOWLEDGED AND ADVISED NEW CLRNC DIRECT DIJON VOR. XING ACFT WAS AN ACR Y, MLG WHO MADE AN INQUIRY TO GENEVA CTL ABOUT OUR ALT. A FACTOR THAT MAY HAVE CAUSED INCIDENT WAS CTLR BEING PREOCCUPIED WITH ANOTHER ACFT WHO WAS TRYING TO GET A NEW AIRWAY CLRNC.

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.