Operational error occurred when ZDV controller failed to provide separation between a B757 and a B747 opposite direction at FL390.

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Attributes
ACN	469667
Time
Date	200004
Day	Tue
Local Time Of Day	0001 To 0600
Place
State Reference	NE
Altitude	msl single value : 39000
Environment
Flight Conditions	VMC
Light	Night
Aircraft 1
Controlling Facilities	artcc : zdv.artcc
Operator	common carrier : air carrier
Make Model Name	B757 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Navigation In Use	other
Flight Phase	cruise : level
Route In Use	enroute airway : j84.airway
Flight Plan	IFR
Aircraft 2
Controlling Facilities	artcc : zdv.artcc
Operator	common carrier : air carrier
Make Model Name	B747 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Flight Phase	cruise : level
Route In Use	enroute airway : j84.airway
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : multi engine pilot : instrument pilot : flight engineer pilot : commercial pilot : atp
Experience	flight time last 90 days : 125 flight time total : 20000 flight time type : 200
ASRS Report	469667
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp pilot : multi engine pilot : flight engineer
Experience	flight time last 90 days : 150 flight time total : 6000 flight time type : 180
ASRS Report	469669
Events
Anomaly	conflict : airborne critical non adherence : published procedure
Independent Detector	aircraft equipment : tcas other flight crewa other flight crewb
Resolutory Action	controller : issued new clearance
Miss Distance	horizontal : 3000 vertical : 1800
Supplementary
Problem Areas	ATC Human Performance Flight Crew Human Performance
Primary Problem	ATC Human Performance
Air Traffic Incident	Operational Error

Narrative:

ZDV on frequency 127.02 failed to give air carrier Y and air carrier X each other's traffic. Air carrier X had been level at FL390 eastbound for about 1 1/2 hours to accommodate a smooth ride. Air carrier Y was level at FL390 wbound. TCASII gave air carrier X a TA then an RA to descend. Air carrier Y was at 12 O'clock and 8-10 mi at our time of initial descent. Air carrier Y was told to immediately climb to FL410. As captain, I immediately hit vertical speed while on autoplt and descended to FL370 at 2000 FPM. I also turned on all landing lights to help air carrier Y spot us. We could not or did not see air carrier Y until he went slightly left over the top of air carrier X. An air safety report was filed with company upon landing in pit. Air carrier Y questioned the controller and somewhat blocked air carrier X's attempt to contact the controller to advise her of our immediate descent to FL370. We were then given a frequency change after a brief apology from the controller.

Original NASA ASRS Text

Title: OPERROR OCCURRED WHEN ZDV CTLR FAILED TO PROVIDE SEPARATION BTWN A B757 AND A B747 OPPOSITE DIRECTION AT FL390.

Narrative: ZDV ON FREQ 127.02 FAILED TO GIVE ACR Y AND ACR X EACH OTHER'S TFC. ACR X HAD BEEN LEVEL AT FL390 EBOUND FOR ABOUT 1 1/2 HRS TO ACCOMMODATE A SMOOTH RIDE. ACR Y WAS LEVEL AT FL390 WBOUND. TCASII GAVE ACR X A TA THEN AN RA TO DSND. ACR Y WAS AT 12 O'CLOCK AND 8-10 MI AT OUR TIME OF INITIAL DSCNT. ACR Y WAS TOLD TO IMMEDIATELY CLB TO FL410. AS CAPT, I IMMEDIATELY HIT VERT SPD WHILE ON AUTOPLT AND DSNDED TO FL370 AT 2000 FPM. I ALSO TURNED ON ALL LNDG LIGHTS TO HELP ACR Y SPOT US. WE COULD NOT OR DID NOT SEE ACR Y UNTIL HE WENT SLIGHTLY L OVER THE TOP OF ACR X. AN AIR SAFETY RPT WAS FILED WITH COMPANY UPON LNDG IN PIT. ACR Y QUESTIONED THE CTLR AND SOMEWHAT BLOCKED ACR X'S ATTEMPT TO CONTACT THE CTLR TO ADVISE HER OF OUR IMMEDIATE DSCNT TO FL370. WE WERE THEN GIVEN A FREQ CHANGE AFTER A BRIEF APOLOGY FROM THE CTLR.

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.