Air carrier using improper phraseology of call sign creates confusion due similar call signs.

Attributes
ACN	205219
Time
Date	199203
Day	Thu
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : ord
State Reference	IL
Altitude	agl bound lower : 0 agl bound upper : 0
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	Large Transport, Low Wing, 3 Turbojet Eng
Flight Phase	ground other : taxi
Flight Plan	IFR
Aircraft 2
Operator	common carrier : air carrier
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Flight Phase	ground other : taxi
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp pilot : cfi pilot : commercial pilot : instrument
Experience	flight time last 90 days : 100 flight time total : 7000 flight time type : 3600
ASRS Report	205219
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : instrument pilot : commercial pilot : atp
Events
Anomaly	non adherence : clearance non adherence : published procedure other anomaly other
Independent Detector	other flight crewa
Resolutory Action	other
Consequence	faa : reviewed incident with flight crew Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

I was the captain on flight aircraft ord-hdn. On taxi out ord metering 121.67 told us to switch to 126.9. I told my copilot who was handling the radio this was extremely unusual. I told him to verify the frequency which he did and he asked for taxi instructions. The tower 126.9 told us to 'go to T1.' so I did. As I was taxiing toward T1 I heard another air carrier on frequency which was ffi at that time I realized that tower thought he was talking to ffi but he was talking to us and we responded as affi up to that point. At that time my copilot said his call sign as a-f-fi and told our location T1. Tower 126.9 told us all to 'stop' so he could sort it out. He told us that he was just about to clear us for takeoff (and we were still on the inner taxiway). We switched back to ground on 121.67 and hence got a chewing out. I believe the ground controller on 121.67 was handling 2 frequencys (the other being 121.75) and thought we were ffi calling him on 121.75. Thus the confusion. My copilot verified all taxiing instructions with a full readback, however ord tower did not realize the problem until we used the call sign properly as a-f-fi rather affi.

Original NASA ASRS Text

Title: ACR USING IMPROPER PHRASEOLOGY OF CALL SIGN CREATES CONFUSION DUE SIMILAR CALL SIGNS.

Narrative: I WAS THE CAPT ON FLT ACFT ORD-HDN. ON TAXI OUT ORD METERING 121.67 TOLD US TO SWITCH TO 126.9. I TOLD MY COPLT WHO WAS HANDLING THE RADIO THIS WAS EXTREMELY UNUSUAL. I TOLD HIM TO VERIFY THE FREQ WHICH HE DID AND HE ASKED FOR TAXI INSTRUCTIONS. THE TWR 126.9 TOLD US TO 'GO TO T1.' SO I DID. AS I WAS TAXIING TOWARD T1 I HEARD ANOTHER ACR ON FREQ WHICH WAS FFI AT THAT TIME I REALIZED THAT TWR THOUGHT HE WAS TALKING TO FFI BUT HE WAS TALKING TO US AND WE RESPONDED AS AFFI UP TO THAT POINT. AT THAT TIME MY COPLT SAID HIS CALL SIGN AS A-F-FI AND TOLD OUR LOCATION T1. TWR 126.9 TOLD US ALL TO 'STOP' SO HE COULD SORT IT OUT. HE TOLD US THAT HE WAS JUST ABOUT TO CLR US FOR TKOF (AND WE WERE STILL ON THE INNER TAXIWAY). WE SWITCHED BACK TO GND ON 121.67 AND HENCE GOT A CHEWING OUT. I BELIEVE THE GND CTLR ON 121.67 WAS HANDLING 2 FREQS (THE OTHER BEING 121.75) AND THOUGHT WE WERE FFI CALLING HIM ON 121.75. THUS THE CONFUSION. MY COPLT VERIFIED ALL TAXIING INSTRUCTIONS WITH A FULL READBACK, HOWEVER ORD TWR DID NOT REALIZE THE PROBLEM UNTIL WE USED THE CALL SIGN PROPERLY AS A-F-FI RATHER AFFI.

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.