Narrative:

Air carrier X en route J60 to mdw was given an incorrect frequency for the lorain sector. Aircraft issued 119.87 which was the ravenna sector stratified under the lorain sector at and below FL310. The aircraft came in conflict with an air carrier Y FL350 southbound en route to atl over the djb (dryer) VORTAC due to the incorrect frequency. The air carrier Y was NORDO. Callback conversation with reporter revealed the following information. Reporter stated that he was a supervisor who was working the sector at the time of the incident. He said that he had been on the sector for approximately 45 min when the incident occurred. He was working combined with an associate radar controller. As soon as air carrier X was changed to the next sector, he knew that he had given the wrong frequency. When the associate radar controller asked if he wanted him to try to get the aircraft back on frequency, the reporter told him no, that the aircraft would come back on his own. The reporter said that he did not know about the NORDO aircraft at that time. He has been pulled off control room floor and currently working staff duties until the investigation is completed. The reporter also mentioned that air carrier Y, the NORDO aircraft, had not talked to ATC since over northern canada. He was en route to atl. The aircraft came 300' vertical and 700' horizontal from one another. Supplemental information from acn 187551. En route from lga to mdw at 35000' we were given a routine radio frequency change from 120.2 to 119.87. We tried to check in on the new frequency several times but were blocked by other xmissions. The controller on this frequency was extremely busy. As I recall, he had to repeat instructions more than once to some aircraft and make more than one call to others to get them to respond. While waiting for a break to check-in, my first officer called out traffic to me at the 2 O'clock position. The traffic, a widebody transport, was in my blind spot (behind a windscreen post). When I saw the aircraft I watched for approximately 10 seconds and determined we were on a collision course. He looked like he might be above me, but definitely not by a safe margin. I initiated an immediate descent out of 35000'. I kept him in sight for awhileand felt comfortable that he wasn't descending and we would pass clear. An employee on board later told me he saw the traffic and felt me push-over. He watched the widebody transport go overhead approximately 1000' above. We had passed 34000' descending when we finally broke-in on the center frequency and reported we left 35000' to avoid a mid-air collision. The controller sounded surprised by our call. A moment later another controller instructed us to continue to 31000' and change to 133.52. I advised the next controller that we had to deviate to avoid a mid-air and requested a phone number to call. I was asked if we had any injuries and I responded no. I was also asked if we were monitoring djb voice. I told them no, I did not have radio failure and I was monitoring an assigned ATC frequency waiting for an opportunity to check in. After landing, I contacted a manager at cleveland center. I was told I was on the frequency assigned to me, but it was an incorrect frequency. It was for a lower cleveland sector 24 to 31000'. The widebody transport was also at 35000' heading south towards djb VOR and was being monitored as a 'radio out' aircraft. I was told they tried to contact me on several frequencys, including djb VOR voice. If any attempt to call me on 119.87 was made, it too must have been blocked. Had it not been for VMC and a very observant first officer, their would have been a mid-air collision. Having had 22 yrs of military formation flying experience, it did not take me long to decide we had a conflict. My concern was if the other aircraft saw us and also started a descent, I would then have had to do some severe maneuvering to avoid a collision. I believe better precautions with a NORDO aircraft should have been taken. I was told that the controller on 120.02 was not aware of the NORDO aircraft at the same altitude heading towards the same point so he could not have advised me prior to the handoff. It is not uncommon for a controller to give an improper frequency and quickly correct himself, or be corrected when you check in on the incorrect frequency. This happens on a daily basis. In this situation the controller on 119.87 was busy giving aircraft altand heading instructions which I consider more important that blocking his xmissions with a routine check in. If you get too insistent with a busy controller, you're usually told to 'stand-by'. Supplemental information from acn 187556. Center knew we were on a wrong frequency but not which one. Logged us NORDO(?). Center also had a widebody transport NORDO over djb same time and altitude as us. Controller apparently making attempts to locate us even transmitting on VOR voice track. I figure we missed by 800' vertical sep. He went directly over us. I'm sure we would have collided had I not seen this aircraft. Entirely too much radio traffic. Too many controller instructions had to be repeated, some 3 times. Supplemental information from acn 189213. This near miss occurred because air carrier Y captain didn't maintain a radio watch over the whole north hemisphere while on a london to atlanta flight and another aircraft was not retrieved from a wrong frequency by a supervisor working radar because of human error. To avoid the helplessness inherent in any lost communications situation ACARS needs to be mandated as TCAS has been. By the way, air carrier X had TCAS but it was OTS and air carrier Y didn't have TCAS. Air carrier Y never saw air carrier X.

Related reports:

Google
 

Original NASA ASRS Text

Title: ACR ISSUED WRONG FREQ TO NEXT SECTOR HAS CONFLICT WITH A NORDO ACR ON CONVERGING COURSE.

Narrative: ACR X ENRTE J60 TO MDW WAS GIVEN AN INCORRECT FREQ FOR THE LORAIN SECTOR. ACFT ISSUED 119.87 WHICH WAS THE RAVENNA SECTOR STRATIFIED UNDER THE LORAIN SECTOR AT AND BELOW FL310. THE ACFT CAME IN CONFLICT WITH AN ACR Y FL350 SBND ENRTE TO ATL OVER THE DJB (DRYER) VORTAC DUE TO THE INCORRECT FREQ. THE ACR Y WAS NORDO. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO. RPTR STATED THAT HE WAS A SUPVR WHO WAS WORKING THE SECTOR AT THE TIME OF THE INCIDENT. HE SAID THAT HE HAD BEEN ON THE SECTOR FOR APPROX 45 MIN WHEN THE INCIDENT OCCURRED. HE WAS WORKING COMBINED WITH AN ASSOCIATE RADAR CTLR. AS SOON AS ACR X WAS CHANGED TO THE NEXT SECTOR, HE KNEW THAT HE HAD GIVEN THE WRONG FREQ. WHEN THE ASSOCIATE RADAR CTLR ASKED IF HE WANTED HIM TO TRY TO GET THE ACFT BACK ON FREQ, THE RPTR TOLD HIM NO, THAT THE ACFT WOULD COME BACK ON HIS OWN. THE RPTR SAID THAT HE DID NOT KNOW ABOUT THE NORDO ACFT AT THAT TIME. HE HAS BEEN PULLED OFF CTL ROOM FLOOR AND CURRENTLY WORKING STAFF DUTIES UNTIL THE INVESTIGATION IS COMPLETED. THE RPTR ALSO MENTIONED THAT ACR Y, THE NORDO ACFT, HAD NOT TALKED TO ATC SINCE OVER NORTHERN CANADA. HE WAS ENRTE TO ATL. THE ACFT CAME 300' VERT AND 700' HORIZ FROM ONE ANOTHER. SUPPLEMENTAL INFO FROM ACN 187551. ENRTE FROM LGA TO MDW AT 35000' WE WERE GIVEN A ROUTINE RADIO FREQ CHANGE FROM 120.2 TO 119.87. WE TRIED TO CHK IN ON THE NEW FREQ SEVERAL TIMES BUT WERE BLOCKED BY OTHER XMISSIONS. THE CTLR ON THIS FREQ WAS EXTREMELY BUSY. AS I RECALL, HE HAD TO REPEAT INSTRUCTIONS MORE THAN ONCE TO SOME ACFT AND MAKE MORE THAN ONE CALL TO OTHERS TO GET THEM TO RESPOND. WHILE WAITING FOR A BREAK TO CHK-IN, MY F/O CALLED OUT TFC TO ME AT THE 2 O'CLOCK POS. THE TFC, A WDB, WAS IN MY BLIND SPOT (BEHIND A WINDSCREEN POST). WHEN I SAW THE ACFT I WATCHED FOR APPROX 10 SECS AND DETERMINED WE WERE ON A COLLISION COURSE. HE LOOKED LIKE HE MIGHT BE ABOVE ME, BUT DEFINITELY NOT BY A SAFE MARGIN. I INITIATED AN IMMEDIATE DSNT OUT OF 35000'. I KEPT HIM IN SIGHT FOR AWHILEAND FELT COMFORTABLE THAT HE WASN'T DSNDING AND WE WOULD PASS CLR. AN EMPLOYEE ON BOARD LATER TOLD ME HE SAW THE TFC AND FELT ME PUSH-OVER. HE WATCHED THE WDB GO OVERHEAD APPROX 1000' ABOVE. WE HAD PASSED 34000' DSNDING WHEN WE FINALLY BROKE-IN ON THE CTR FREQ AND RPTED WE L 35000' TO AVOID A MID-AIR COLLISION. THE CTLR SOUNDED SURPRISED BY OUR CALL. A MOMENT LATER ANOTHER CTLR INSTRUCTED US TO CONTINUE TO 31000' AND CHANGE TO 133.52. I ADVISED THE NEXT CTLR THAT WE HAD TO DEVIATE TO AVOID A MID-AIR AND REQUESTED A PHONE NUMBER TO CALL. I WAS ASKED IF WE HAD ANY INJURIES AND I RESPONDED NO. I WAS ALSO ASKED IF WE WERE MONITORING DJB VOICE. I TOLD THEM NO, I DID NOT HAVE RADIO FAILURE AND I WAS MONITORING AN ASSIGNED ATC FREQ WAITING FOR AN OPPORTUNITY TO CHK IN. AFTER LNDG, I CONTACTED A MGR AT CLEVELAND CTR. I WAS TOLD I WAS ON THE FREQ ASSIGNED TO ME, BUT IT WAS AN INCORRECT FREQ. IT WAS FOR A LOWER CLEVELAND SECTOR 24 TO 31000'. THE WDB WAS ALSO AT 35000' HDG S TOWARDS DJB VOR AND WAS BEING MONITORED AS A 'RADIO OUT' ACFT. I WAS TOLD THEY TRIED TO CONTACT ME ON SEVERAL FREQS, INCLUDING DJB VOR VOICE. IF ANY ATTEMPT TO CALL ME ON 119.87 WAS MADE, IT TOO MUST HAVE BEEN BLOCKED. HAD IT NOT BEEN FOR VMC AND A VERY OBSERVANT F/O, THEIR WOULD HAVE BEEN A MID-AIR COLLISION. HAVING HAD 22 YRS OF MIL FORMATION FLYING EXPERIENCE, IT DID NOT TAKE ME LONG TO DECIDE WE HAD A CONFLICT. MY CONCERN WAS IF THE OTHER ACFT SAW US AND ALSO STARTED A DSNT, I WOULD THEN HAVE HAD TO DO SOME SEVERE MANEUVERING TO AVOID A COLLISION. I BELIEVE BETTER PRECAUTIONS WITH A NORDO ACFT SHOULD HAVE BEEN TAKEN. I WAS TOLD THAT THE CTLR ON 120.02 WAS NOT AWARE OF THE NORDO ACFT AT THE SAME ALT HDG TOWARDS THE SAME POINT SO HE COULD NOT HAVE ADVISED ME PRIOR TO THE HDOF. IT IS NOT UNCOMMON FOR A CTLR TO GIVE AN IMPROPER FREQ AND QUICKLY CORRECT HIMSELF, OR BE CORRECTED WHEN YOU CHK IN ON THE INCORRECT FREQ. THIS HAPPENS ON A DAILY BASIS. IN THIS SITUATION THE CTLR ON 119.87 WAS BUSY GIVING ACFT ALTAND HDG INSTRUCTIONS WHICH I CONSIDER MORE IMPORTANT THAT BLOCKING HIS XMISSIONS WITH A ROUTINE CHK IN. IF YOU GET TOO INSISTENT WITH A BUSY CTLR, YOU'RE USUALLY TOLD TO 'STAND-BY'. SUPPLEMENTAL INFO FROM ACN 187556. CTR KNEW WE WERE ON A WRONG FREQ BUT NOT WHICH ONE. LOGGED US NORDO(?). CTR ALSO HAD A WDB NORDO OVER DJB SAME TIME AND ALT AS US. CTLR APPARENTLY MAKING ATTEMPTS TO LOCATE US EVEN XMITTING ON VOR VOICE TRACK. I FIGURE WE MISSED BY 800' VERT SEP. HE WENT DIRECTLY OVER US. I'M SURE WE WOULD HAVE COLLIDED HAD I NOT SEEN THIS ACFT. ENTIRELY TOO MUCH RADIO TFC. TOO MANY CTLR INSTRUCTIONS HAD TO BE REPEATED, SOME 3 TIMES. SUPPLEMENTAL INFO FROM ACN 189213. THIS NEAR MISS OCCURRED BECAUSE ACR Y CAPT DIDN'T MAINTAIN A RADIO WATCH OVER THE WHOLE N HEMISPHERE WHILE ON A LONDON TO ATLANTA FLT AND ANOTHER ACFT WAS NOT RETRIEVED FROM A WRONG FREQ BY A SUPERVISOR WORKING RADAR BECAUSE OF HUMAN ERROR. TO AVOID THE HELPLESSNESS INHERENT IN ANY LOST COMS SITUATION ACARS NEEDS TO BE MANDATED AS TCAS HAS BEEN. BY THE WAY, ACR X HAD TCAS BUT IT WAS OTS AND ACR Y DIDN'T HAVE TCAS. ACR Y NEVER SAW ACR X.

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.