B737 and unknown aircraft had less than legal separation.

Attributes
ACN	421477
Time
Date	199811
Day	Thu
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : fwa
State Reference	IN
Altitude	msl bound lower : 33000 msl bound upper : 33500
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	B737-300
Operating Under FAR Part	Part 121
Flight Phase	cruise other
Flight Plan	IFR
Aircraft 2
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Operating Under FAR Part	other : unkown
Flight Phase	cruise other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : flight engineer
Experience	flight time last 90 days : 200 flight time total : 14000 flight time type : 3000
ASRS Report	421477
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : commercial
Events
Anomaly	conflict : airborne less severe non adherence : required legal separation
Independent Detector	aircraft equipment other aircraft equipment : unspecified other flight crewa
Consequence	Other
Miss Distance	horizontal : 30000 vertical : 500
Supplementary
Air Traffic Incident	Intra Facility Coordination Failure other

Narrative:

While en route from ewr to sjc we had been at a cruise altitude of FL310 with a request in to the center for FL350. They were unable to give us FL350 at the time of the request due to conflicting traffic. 5 mins or so after the request for FL350, center told us to climb to FL330. We did so after acknowledging the altitude change. During climb, for 2-3 mins, center came back with a clearance to turn left 30 degrees. At the same moment, we noticed an aircraft pop up in our TCASII that was at our 1 O'clock position, 5 mi and +500 ft above us. We received a TCASII advisory ('traffic, traffic'). We made the heading adjustment, had a visual on the traffic and continued the climb. ATC then gave us a frequency change. The next controller gave us FL350 and cleared us back on course. Nothing was said about the situation and the flight continued normally from there on. I suspect that at the time of the altitude change, that we were at the edge of a controller's area. He gave us the altitude change unaware of conflicting traffic in the opposite direction. Once it became apparent of a conflict we were given the heading change. I suspect poor communication between sector controllers resulted in the conflict.

Original NASA ASRS Text

Title: B737 AND UNKNOWN ACFT HAD LESS THAN LEGAL SEPARATION.

Narrative: WHILE ENRTE FROM EWR TO SJC WE HAD BEEN AT A CRUISE ALT OF FL310 WITH A REQUEST IN TO THE CTR FOR FL350. THEY WERE UNABLE TO GIVE US FL350 AT THE TIME OF THE REQUEST DUE TO CONFLICTING TFC. 5 MINS OR SO AFTER THE REQUEST FOR FL350, CTR TOLD US TO CLB TO FL330. WE DID SO AFTER ACKNOWLEDGING THE ALT CHANGE. DURING CLB, FOR 2-3 MINS, CTR CAME BACK WITH A CLRNC TO TURN L 30 DEGS. AT THE SAME MOMENT, WE NOTICED AN ACFT POP UP IN OUR TCASII THAT WAS AT OUR 1 O'CLOCK POS, 5 MI AND +500 FT ABOVE US. WE RECEIVED A TCASII ADVISORY ('TFC, TFC'). WE MADE THE HDG ADJUSTMENT, HAD A VISUAL ON THE TFC AND CONTINUED THE CLB. ATC THEN GAVE US A FREQ CHANGE. THE NEXT CTLR GAVE US FL350 AND CLRED US BACK ON COURSE. NOTHING WAS SAID ABOUT THE SIT AND THE FLT CONTINUED NORMALLY FROM THERE ON. I SUSPECT THAT AT THE TIME OF THE ALT CHANGE, THAT WE WERE AT THE EDGE OF A CTLR'S AREA. HE GAVE US THE ALT CHANGE UNAWARE OF CONFLICTING TFC IN THE OPPOSITE DIRECTION. ONCE IT BECAME APPARENT OF A CONFLICT WE WERE GIVEN THE HDG CHANGE. I SUSPECT POOR COM BTWN SECTOR CTLRS RESULTED IN THE CONFLICT.

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.