Narrative:

The captain was taxiing the aircraft (appropriately, scanning outside the cockpit to ensure safety). At the direction of ground control, I contacted what I had thought was ramp control on xyz.12. I did not realize it at the time, but I had inadvertently dialed on xyz.23 (air carrier a operations). I reported, 'ramp control, this is air carrier A1 on taxiway F5 for gate X.' a voice replied, 'roger, you're cleared in to the gate.' thinking that we had received ramp control clearance, we proceeded to the gate. We observed an air carrier B757 parked on gate X+4 or X+5. His anti-collision lights were not illuminated. As we passed behind his tail, I observed 'wing walker' personnel begin to assemble at his wingtips in preparation for push back. In addition, we observed a company B737-200, which had completed push back off of gate X-2. His towbar had been disconnected, and he had commenced taxi, sbound, away from us. There was no other traffic, and in both cases, there was no conflict or interference of any kind. After we had parked and shut down, a voice on the radio (air carrier a operations) contacted us and stated, 'ramp control wants you to call them.' puzzled at first, I then realized my frequency error! The ramp controller sounded very annoyed and informed me that we had 'nearly caused an accident.' I briefly apologized, admitted my error, and explained what had happened. However, puzzled and concerned about her remark, I politely requested that she amplify it. She replied, in effect, that she had to 'stop the B757's push' in order to 'avoid a conflict.' rather than sound unprofessional and get into an argument on the radio, I again apologized. I then, with the captain's concurrence, proceeded with him to operations, obtained the phone number for ramp control and called. I spoke directly to the ramp controller involved. She said that she understood and thanked me for calling. In response to a query from me, she pleasantly remarked that there was 'no problem.' contributing factors: 1) fatigue. Third day of 4-DAY trip, last leg, up since early morning. 2) complacency on my part. I'd been to atl, and I am familiar with local procedures. 3) operations frequency was more prominently displayed in much darker numerals on the airport/ramp diagram than the ramp control frequency. It was also on the ACARS screen with the gate assignment. 4) operations didn't notice that I had contacted them, initially, as 'ramp control.' the error was all mine, though! Corrective action/recommendations: although safety was not an issue here, fatigue is an insidious thing. A pilot must really pay attention to detail and make sure you're on the current frequency -- especially when you are tired!

Related reports:

Google
 

Original NASA ASRS Text

Title: MLG ACFT TAXIING TO GATE, FLC CONTACTED WHAT THEY THOUGHT WAS RAMP CTLR, BUT WERE ON THE WRONG FREQ AND CALLED THEIR COMPANY OPS INSTEAD, WHO TOLD THEM THEY WERE CLRED TO THE GATE. AS THEY APCHED THE GATE AREA THERE WERE EVIDENT COORD PROBS BTWN ACFT PUSHING BACK, TAXIING, ETC. RPTR'S COMPANY REQUESTED THEY CALL WHEN THEY PARKED AND ADVISED THEM THAT THEY HAD NOT RECEIVED CLRNC FROM RAMP CTL. RPTR REALIZED THE ERROR IN USING THE INCORRECT FREQ FOR RAMP CTL.

Narrative: THE CAPT WAS TAXIING THE ACFT (APPROPRIATELY, SCANNING OUTSIDE THE COCKPIT TO ENSURE SAFETY). AT THE DIRECTION OF GND CTL, I CONTACTED WHAT I HAD THOUGHT WAS RAMP CTL ON XYZ.12. I DID NOT REALIZE IT AT THE TIME, BUT I HAD INADVERTENTLY DIALED ON XYZ.23 (ACR A OPS). I RPTED, 'RAMP CTL, THIS IS ACR A1 ON TXWY F5 FOR GATE X.' A VOICE REPLIED, 'ROGER, YOU'RE CLRED IN TO THE GATE.' THINKING THAT WE HAD RECEIVED RAMP CTL CLRNC, WE PROCEEDED TO THE GATE. WE OBSERVED AN ACR B757 PARKED ON GATE X+4 OR X+5. HIS ANTI-COLLISION LIGHTS WERE NOT ILLUMINATED. AS WE PASSED BEHIND HIS TAIL, I OBSERVED 'WING WALKER' PERSONNEL BEGIN TO ASSEMBLE AT HIS WINGTIPS IN PREPARATION FOR PUSH BACK. IN ADDITION, WE OBSERVED A COMPANY B737-200, WHICH HAD COMPLETED PUSH BACK OFF OF GATE X-2. HIS TOWBAR HAD BEEN DISCONNECTED, AND HE HAD COMMENCED TAXI, SBOUND, AWAY FROM US. THERE WAS NO OTHER TFC, AND IN BOTH CASES, THERE WAS NO CONFLICT OR INTERFERENCE OF ANY KIND. AFTER WE HAD PARKED AND SHUT DOWN, A VOICE ON THE RADIO (ACR A OPS) CONTACTED US AND STATED, 'RAMP CTL WANTS YOU TO CALL THEM.' PUZZLED AT FIRST, I THEN REALIZED MY FREQ ERROR! THE RAMP CTLR SOUNDED VERY ANNOYED AND INFORMED ME THAT WE HAD 'NEARLY CAUSED AN ACCIDENT.' I BRIEFLY APOLOGIZED, ADMITTED MY ERROR, AND EXPLAINED WHAT HAD HAPPENED. HOWEVER, PUZZLED AND CONCERNED ABOUT HER REMARK, I POLITELY REQUESTED THAT SHE AMPLIFY IT. SHE REPLIED, IN EFFECT, THAT SHE HAD TO 'STOP THE B757'S PUSH' IN ORDER TO 'AVOID A CONFLICT.' RATHER THAN SOUND UNPROFESSIONAL AND GET INTO AN ARGUMENT ON THE RADIO, I AGAIN APOLOGIZED. I THEN, WITH THE CAPT'S CONCURRENCE, PROCEEDED WITH HIM TO OPS, OBTAINED THE PHONE NUMBER FOR RAMP CTL AND CALLED. I SPOKE DIRECTLY TO THE RAMP CTLR INVOLVED. SHE SAID THAT SHE UNDERSTOOD AND THANKED ME FOR CALLING. IN RESPONSE TO A QUERY FROM ME, SHE PLEASANTLY REMARKED THAT THERE WAS 'NO PROB.' CONTRIBUTING FACTORS: 1) FATIGUE. THIRD DAY OF 4-DAY TRIP, LAST LEG, UP SINCE EARLY MORNING. 2) COMPLACENCY ON MY PART. I'D BEEN TO ATL, AND I AM FAMILIAR WITH LCL PROCS. 3) OPS FREQ WAS MORE PROMINENTLY DISPLAYED IN MUCH DARKER NUMERALS ON THE ARPT/RAMP DIAGRAM THAN THE RAMP CTL FREQ. IT WAS ALSO ON THE ACARS SCREEN WITH THE GATE ASSIGNMENT. 4) OPS DIDN'T NOTICE THAT I HAD CONTACTED THEM, INITIALLY, AS 'RAMP CTL.' THE ERROR WAS ALL MINE, THOUGH! CORRECTIVE ACTION/RECOMMENDATIONS: ALTHOUGH SAFETY WAS NOT AN ISSUE HERE, FATIGUE IS AN INSIDIOUS THING. A PLT MUST REALLY PAY ATTN TO DETAIL AND MAKE SURE YOU'RE ON THE CURRENT FREQ -- ESPECIALLY WHEN YOU ARE TIRED!

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.