Narrative:

I was working the radar position R-48 georgetown at ZJX. I received the handoff on A330 (aircraft #1) from ZDC R-09 and they checked on the frequency at FL400 while still in ZDC airspace (about 20 mi from my boundary). I had switched B737 (aircraft #2) at FL390 to ZDC R-09 a few mins before; and after B737 crossed the center boundary into ZDC airspace; I noticed that his altitude was showing FL393. This can be a common occurrence as we sometimes get bad radar hits and the next update will show them level. The next update; however; showed the altitude as FL395. I called sector 09 on the landline asking what was the B737 doing since he had traffic head-on at FL400 and 8 mi. I received no response from the sector. I hung up the landline and told A330 to turn right heading 270 degrees as I observed that B737 was now showing level at FL400. He responded that he had a TCAS alert and was descending. I called to sector 09 to tell them that A330 was now descending due to TCAS. Again; I received no response. As the aircraft passed; I showed that B737 was now back level at FL390. I don't know if separation was lost or how close the aircraft were; but the targets did pass within 1 mi of each other. I never did get any responses from the ZDC sector 09; so I do not know what happened with the B737 -- whether he had any TCAS alerts or if the controller had climbed or descended him. I called A330 after the incident and apologized; saying that I wasn't talking to the other pilot so I don't know what he was doing. He responded that he wanted the call sign of the other aircraft because he needed to file a TCAS report. I told him it was B737 that was on ZDC frequency. I don't know what the cause of this incident was whether it was controller or pilot error or both since I never could talk to the controller via the landline. When I later called the sector; a different controller answered and didn't know what had happened. Possible contributing factors could be that there was lots of WX in the area. Most aircraft were deviating around storms and buildups in the area near the incident. I was very busy at the time as I'm sure the ZDC controller was as well due to all the tx deviations. Once a pilot says they are responding to their TCAS; the controller can't do anything but watch as the TCAS is supposed to separate the aircraft and you may give instructions contrary to TCAS on one of the aircraft and things could be even worse. Therefore; I don't know that there was anything I could have done differently as I tried to turn the A330 as soon as I saw that the aircraft were coming closer to each other. Supplemental information from acn 667537: B737 checked on to the frequency at FL390 requesting FL410. B737 request for an altitude change was acknowledged. Upon entering ZDC's airspace; B737 was issued a climb clearance to FL410. The conflict alert activated as B737 was observed at FL399 climbing to FL410. I issued an immediate descent to FL380; then I called jacksonville center to advise them that B737 was descending. A330 was observed climbing to FL405. Subsequently B737 reported leaving FL390 for FL380.

Google
 

Original NASA ASRS Text

Title: BOTH ZJX AND ZDC CTLRS CHRONICLE EVENTS LEADING UP TO OPERROR AT FL400 IN CLOSE PROX OF COMMON AIRSPACE BOUNDARY.

Narrative: I WAS WORKING THE RADAR POS R-48 GEORGETOWN AT ZJX. I RECEIVED THE HDOF ON A330 (ACFT #1) FROM ZDC R-09 AND THEY CHKED ON THE FREQ AT FL400 WHILE STILL IN ZDC AIRSPACE (ABOUT 20 MI FROM MY BOUNDARY). I HAD SWITCHED B737 (ACFT #2) AT FL390 TO ZDC R-09 A FEW MINS BEFORE; AND AFTER B737 CROSSED THE CTR BOUNDARY INTO ZDC AIRSPACE; I NOTICED THAT HIS ALT WAS SHOWING FL393. THIS CAN BE A COMMON OCCURRENCE AS WE SOMETIMES GET BAD RADAR HITS AND THE NEXT UPDATE WILL SHOW THEM LEVEL. THE NEXT UPDATE; HOWEVER; SHOWED THE ALT AS FL395. I CALLED SECTOR 09 ON THE LANDLINE ASKING WHAT WAS THE B737 DOING SINCE HE HAD TFC HEAD-ON AT FL400 AND 8 MI. I RECEIVED NO RESPONSE FROM THE SECTOR. I HUNG UP THE LANDLINE AND TOLD A330 TO TURN R HDG 270 DEGS AS I OBSERVED THAT B737 WAS NOW SHOWING LEVEL AT FL400. HE RESPONDED THAT HE HAD A TCAS ALERT AND WAS DSNDING. I CALLED TO SECTOR 09 TO TELL THEM THAT A330 WAS NOW DSNDING DUE TO TCAS. AGAIN; I RECEIVED NO RESPONSE. AS THE ACFT PASSED; I SHOWED THAT B737 WAS NOW BACK LEVEL AT FL390. I DON'T KNOW IF SEPARATION WAS LOST OR HOW CLOSE THE ACFT WERE; BUT THE TARGETS DID PASS WITHIN 1 MI OF EACH OTHER. I NEVER DID GET ANY RESPONSES FROM THE ZDC SECTOR 09; SO I DO NOT KNOW WHAT HAPPENED WITH THE B737 -- WHETHER HE HAD ANY TCAS ALERTS OR IF THE CTLR HAD CLBED OR DSNDED HIM. I CALLED A330 AFTER THE INCIDENT AND APOLOGIZED; SAYING THAT I WASN'T TALKING TO THE OTHER PLT SO I DON'T KNOW WHAT HE WAS DOING. HE RESPONDED THAT HE WANTED THE CALL SIGN OF THE OTHER ACFT BECAUSE HE NEEDED TO FILE A TCAS RPT. I TOLD HIM IT WAS B737 THAT WAS ON ZDC FREQ. I DON'T KNOW WHAT THE CAUSE OF THIS INCIDENT WAS WHETHER IT WAS CTLR OR PLT ERROR OR BOTH SINCE I NEVER COULD TALK TO THE CTLR VIA THE LANDLINE. WHEN I LATER CALLED THE SECTOR; A DIFFERENT CTLR ANSWERED AND DIDN'T KNOW WHAT HAD HAPPENED. POSSIBLE CONTRIBUTING FACTORS COULD BE THAT THERE WAS LOTS OF WX IN THE AREA. MOST ACFT WERE DEVIATING AROUND STORMS AND BUILDUPS IN THE AREA NEAR THE INCIDENT. I WAS VERY BUSY AT THE TIME AS I'M SURE THE ZDC CTLR WAS AS WELL DUE TO ALL THE TX DEVIATIONS. ONCE A PLT SAYS THEY ARE RESPONDING TO THEIR TCAS; THE CTLR CAN'T DO ANYTHING BUT WATCH AS THE TCAS IS SUPPOSED TO SEPARATE THE ACFT AND YOU MAY GIVE INSTRUCTIONS CONTRARY TO TCAS ON ONE OF THE ACFT AND THINGS COULD BE EVEN WORSE. THEREFORE; I DON'T KNOW THAT THERE WAS ANYTHING I COULD HAVE DONE DIFFERENTLY AS I TRIED TO TURN THE A330 AS SOON AS I SAW THAT THE ACFT WERE COMING CLOSER TO EACH OTHER. SUPPLEMENTAL INFO FROM ACN 667537: B737 CHKED ON TO THE FREQ AT FL390 REQUESTING FL410. B737 REQUEST FOR AN ALT CHANGE WAS ACKNOWLEDGED. UPON ENTERING ZDC'S AIRSPACE; B737 WAS ISSUED A CLB CLRNC TO FL410. THE CONFLICT ALERT ACTIVATED AS B737 WAS OBSERVED AT FL399 CLBING TO FL410. I ISSUED AN IMMEDIATE DSCNT TO FL380; THEN I CALLED JACKSONVILLE CTR TO ADVISE THEM THAT B737 WAS DESCENDING. A330 WAS OBSERVED CLBING TO FL405. SUBSEQUENTLY B737 REPORTED LEAVING FL390 FOR FL380.

Data retrieved from NASA's ASRS site as of January 2009 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.