Narrative:

I am a controller at ZAU and filed an unsatisfactory condition report on 9/sun/89. I am forwarding a copy of this report. The fwa sector had a system error involving cpr X and air carrier X. The controller was very busy with 14 aircraft on the frequency. The error occurred because air carrier X took a clearance that was intended for cpr X. Our quality assurance office determined the cpr X and air carrier X were similar call signs and that the controller should have used the company name before and after the flight # when issuing his clrncs. This, I think, is a rather simplistic answer. The controller was busy and to issue clrncs to all similar call signs during such a rush would make busy periods at ZAU almost unworkable. Management should also have a responsibility to eliminate such situations from occurring, and flow control should see to it that a sector never gets so busy that using the company name before and after the flight # causes any disruptions in our service. Blaming the entire situation on the controller who did not say 'air carrier X air carrier' and 'cpr X cpr' will not solve the problem. The pilot who misread the clearance should share part of the responsibility, and so should the people who are in charge of the area and do nothing when similar call sign situations are brought to their attention. The reason I brought this situation to your attention is that I worked the rush at the plant sector. During that period, I worked 5 aircraft which could be interpreted as having similar call signs: air carrier, air carrier, air carrier, air carrier and air carrier. I had to emphasize the #'south, speak slowly and use the company name before and after each # numerous times. This is a confusing situation which should be eliminated. We usually report the situation to the supervisor in charge and he fills out the necessary papers to see if the call signs could be changed. But some time ago, we had a similar problem with air carrier X, different company X and different company X being on the frequency during the plant afternoon rush. We complained and filled out the necessary papers for yrs before the call signs were finally changed. I think that it is time to speed that process just a little, so that we can avoid the confusion that occurred between air carrier X and cpr X.

Related reports:

Google
 

Original NASA ASRS Text

Title: SIMILAR ACFT CALL SIGNS AND NUMBERS.

Narrative: I AM A CTLR AT ZAU AND FILED AN UNSATISFACTORY CONDITION RPT ON 9/SUN/89. I AM FORWARDING A COPY OF THIS RPT. THE FWA SECTOR HAD A SYS ERROR INVOLVING CPR X AND ACR X. THE CTLR WAS VERY BUSY WITH 14 ACFT ON THE FREQ. THE ERROR OCCURRED BECAUSE ACR X TOOK A CLRNC THAT WAS INTENDED FOR CPR X. OUR QUALITY ASSURANCE OFFICE DETERMINED THE CPR X AND ACR X WERE SIMILAR CALL SIGNS AND THAT THE CTLR SHOULD HAVE USED THE COMPANY NAME BEFORE AND AFTER THE FLT # WHEN ISSUING HIS CLRNCS. THIS, I THINK, IS A RATHER SIMPLISTIC ANSWER. THE CTLR WAS BUSY AND TO ISSUE CLRNCS TO ALL SIMILAR CALL SIGNS DURING SUCH A RUSH WOULD MAKE BUSY PERIODS AT ZAU ALMOST UNWORKABLE. MGMNT SHOULD ALSO HAVE A RESPONSIBILITY TO ELIMINATE SUCH SITUATIONS FROM OCCURRING, AND FLOW CTL SHOULD SEE TO IT THAT A SECTOR NEVER GETS SO BUSY THAT USING THE COMPANY NAME BEFORE AND AFTER THE FLT # CAUSES ANY DISRUPTIONS IN OUR SVC. BLAMING THE ENTIRE SITUATION ON THE CTLR WHO DID NOT SAY 'ACR X ACR' AND 'CPR X CPR' WILL NOT SOLVE THE PROB. THE PLT WHO MISREAD THE CLRNC SHOULD SHARE PART OF THE RESPONSIBILITY, AND SO SHOULD THE PEOPLE WHO ARE IN CHARGE OF THE AREA AND DO NOTHING WHEN SIMILAR CALL SIGN SITUATIONS ARE BROUGHT TO THEIR ATTN. THE REASON I BROUGHT THIS SITUATION TO YOUR ATTN IS THAT I WORKED THE RUSH AT THE PLANT SECTOR. DURING THAT PERIOD, I WORKED 5 ACFT WHICH COULD BE INTERPRETED AS HAVING SIMILAR CALL SIGNS: ACR, ACR, ACR, ACR AND ACR. I HAD TO EMPHASIZE THE #'S, SPEAK SLOWLY AND USE THE COMPANY NAME BEFORE AND AFTER EACH # NUMEROUS TIMES. THIS IS A CONFUSING SITUATION WHICH SHOULD BE ELIMINATED. WE USUALLY RPT THE SITUATION TO THE SUPVR IN CHARGE AND HE FILLS OUT THE NECESSARY PAPERS TO SEE IF THE CALL SIGNS COULD BE CHANGED. BUT SOME TIME AGO, WE HAD A SIMILAR PROB WITH ACR X, DIFFERENT COMPANY X AND DIFFERENT COMPANY X BEING ON THE FREQ DURING THE PLANT AFTERNOON RUSH. WE COMPLAINED AND FILLED OUT THE NECESSARY PAPERS FOR YRS BEFORE THE CALL SIGNS WERE FINALLY CHANGED. I THINK THAT IT IS TIME TO SPD THAT PROCESS JUST A LITTLE, SO THAT WE CAN AVOID THE CONFUSION THAT OCCURRED BTWN ACR X AND CPR X.

Data retrieved from NASA's ASRS site as of August 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.