Narrative:

We were an XX00 pm departure from ord and the airport was extremely busy. The tower controller was working takeoffs using frequency 132.7 which was not published on the airport plate. There was quite a bit of static on the radios. The plane ahead of us was cleared for takeoff and it came in statically and when the crew asked for a clarification, the controller came back in a very sharp tone to listen up and cleared for takeoff. Next we were cleared into position and hold. Our call sign was air carrier X, dxy. We sat on the runway for about 2 mins and then thought we heard air carrier X, dxy cleared for takeoff. Once again, like the previous aircraft, there was static on the radios. I questioned the takeoff clearance due to the static on the first reception and the controller replied affirmative cleared for an immediate takeoff, I will give you a turn in the air. I then replied air carrier X, dxy rolling. As soon as we were airborne, tower called us and said air carrier X, dxy what are you doing? I never cleared you for takeoff, I cleared air carrier Y, fxy for takeoff, you never had a takeoff clearance. He then left us on runway heading and sent us to departure control. I never thought something like this could ever happen to me. I have read about this happening and have always thought that it was due to inattn by the pilots and a lack of professionalism. But now I believe that, due to the intense situation and some shortcuts in radio xmissions, that this is a very easy occurrence. Some of the factors involved in this situation was first, the tower controller was working a split frequency and was working 2 runways -- 32L and 32R. The 2 frequencys were 132.7 for 32L and 126.9 for 32R. We did not know he was working 2 runways and could not hear any replies on 126.9. We discovered this when the captain talked to mr X, the tower supervisor. We believe that, due to the rushed situation in trying to get air carrier Y to takeoff, the controller dropped the prefix (air carrier Y) and the suffix (heavy) and just transmitted fxy. When I questioned the takeoff clearance, mr X said both us and air carrier Y questioned it at the same time with the same verbiage. The controller heard what he needed to hear and then cleared fxy for an immediate takeoff. Some of the problems we the 1)static on the radios, 2) they were close to putting another controller on to handle the other runway, but delayed waiting until it got a little busier. 3) we did not know another similar sounding call sign was being used on the airport or that the tower controller was working 2 runways. 4) next, the stressful tone of the controller and the problem with the previous aircraft that took off from 32L put us in a hurry state of mind. 5) next, the controller, either due to the static or being under a lot of pressure, started to take shortcuts in the call sign because we never heard him use air carrier Y fxy heavy cleared for takeoff, either the air carrier Y or heavy would have flagged us that he had not cleared us for takeoff. Another air carrier X aircraft behind us for takeoff on 32L. After we were airborne and the tower said he did not clear us for takeoff, the other air carrier aircraft said that, yes, he did clear us, air carrier X, dxy, for takeoff. Therefore, he had heard the same clearance we heard. I accept 1/2 the responsibility for this occurrence because I normally am very specific in acknowledging clrncs using our full call sign and clearance. In this occurrence, I thought a conflict was about to occur due to the transmission of 'cleared for an immediate' takeoff that to expedite, I shortened my reply to X, dxy rolling instead of air carrier X dxy cleared for takeoff from 32L. The best lesson learned is never get caught up in go, go state of mind and always situation back and take your time to be sure you hear what you are supposed to hear.

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Original NASA ASRS Text

Title: UNAUTHORIZED TKOF RWY OP RESULTS IN UNAUTHORIZED UNCOORD PENETRATION OF AIRSPACE. PROX OF ATA TCA.

Narrative: WE WERE AN XX00 PM DEP FROM ORD AND THE ARPT WAS EXTREMELY BUSY. THE TWR CTLR WAS WORKING TKOFS USING FREQ 132.7 WHICH WAS NOT PUBLISHED ON THE ARPT PLATE. THERE WAS QUITE A BIT OF STATIC ON THE RADIOS. THE PLANE AHEAD OF US WAS CLRED FOR TKOF AND IT CAME IN STATICALLY AND WHEN THE CREW ASKED FOR A CLARIFICATION, THE CTLR CAME BACK IN A VERY SHARP TONE TO LISTEN UP AND CLRED FOR TKOF. NEXT WE WERE CLRED INTO POS AND HOLD. OUR CALL SIGN WAS ACR X, DXY. WE SAT ON THE RWY FOR ABOUT 2 MINS AND THEN THOUGHT WE HEARD ACR X, DXY CLRED FOR TKOF. ONCE AGAIN, LIKE THE PREVIOUS ACFT, THERE WAS STATIC ON THE RADIOS. I QUESTIONED THE TKOF CLRNC DUE TO THE STATIC ON THE FIRST RECEPTION AND THE CTLR REPLIED AFFIRMATIVE CLRED FOR AN IMMEDIATE TKOF, I WILL GIVE YOU A TURN IN THE AIR. I THEN REPLIED ACR X, DXY ROLLING. AS SOON AS WE WERE AIRBORNE, TWR CALLED US AND SAID ACR X, DXY WHAT ARE YOU DOING? I NEVER CLRED YOU FOR TKOF, I CLRED ACR Y, FXY FOR TKOF, YOU NEVER HAD A TKOF CLRNC. HE THEN LEFT US ON RWY HDG AND SENT US TO DEP CTL. I NEVER THOUGHT SOMETHING LIKE THIS COULD EVER HAPPEN TO ME. I HAVE READ ABOUT THIS HAPPENING AND HAVE ALWAYS THOUGHT THAT IT WAS DUE TO INATTN BY THE PLTS AND A LACK OF PROFESSIONALISM. BUT NOW I BELIEVE THAT, DUE TO THE INTENSE SITUATION AND SOME SHORTCUTS IN RADIO XMISSIONS, THAT THIS IS A VERY EASY OCCURRENCE. SOME OF THE FACTORS INVOLVED IN THIS SITUATION WAS FIRST, THE TWR CTLR WAS WORKING A SPLIT FREQ AND WAS WORKING 2 RWYS -- 32L AND 32R. THE 2 FREQS WERE 132.7 FOR 32L AND 126.9 FOR 32R. WE DID NOT KNOW HE WAS WORKING 2 RWYS AND COULD NOT HEAR ANY REPLIES ON 126.9. WE DISCOVERED THIS WHEN THE CAPT TALKED TO MR X, THE TWR SUPVR. WE BELIEVE THAT, DUE TO THE RUSHED SITUATION IN TRYING TO GET ACR Y TO TKOF, THE CTLR DROPPED THE PREFIX (ACR Y) AND THE SUFFIX (HVY) AND JUST XMITTED FXY. WHEN I QUESTIONED THE TKOF CLRNC, MR X SAID BOTH US AND ACR Y QUESTIONED IT AT THE SAME TIME WITH THE SAME VERBIAGE. THE CTLR HEARD WHAT HE NEEDED TO HEAR AND THEN CLRED FXY FOR AN IMMEDIATE TKOF. SOME OF THE PROBLEMS WE THE 1)STATIC ON THE RADIOS, 2) THEY WERE CLOSE TO PUTTING ANOTHER CTLR ON TO HANDLE THE OTHER RWY, BUT DELAYED WAITING UNTIL IT GOT A LITTLE BUSIER. 3) WE DID NOT KNOW ANOTHER SIMILAR SOUNDING CALL SIGN WAS BEING USED ON THE ARPT OR THAT THE TWR CTLR WAS WORKING 2 RWYS. 4) NEXT, THE STRESSFUL TONE OF THE CTLR AND THE PROBLEM WITH THE PREVIOUS ACFT THAT TOOK OFF FROM 32L PUT US IN A HURRY STATE OF MIND. 5) NEXT, THE CTLR, EITHER DUE TO THE STATIC OR BEING UNDER A LOT OF PRESSURE, STARTED TO TAKE SHORTCUTS IN THE CALL SIGN BECAUSE WE NEVER HEARD HIM USE ACR Y FXY HVY CLRED FOR TKOF, EITHER THE ACR Y OR HVY WOULD HAVE FLAGGED US THAT HE HAD NOT CLRED US FOR TKOF. ANOTHER ACR X ACFT BEHIND US FOR TKOF ON 32L. AFTER WE WERE AIRBORNE AND THE TWR SAID HE DID NOT CLR US FOR TKOF, THE OTHER ACR ACFT SAID THAT, YES, HE DID CLR US, ACR X, DXY, FOR TKOF. THEREFORE, HE HAD HEARD THE SAME CLRNC WE HEARD. I ACCEPT 1/2 THE RESPONSIBILITY FOR THIS OCCURRENCE BECAUSE I NORMALLY AM VERY SPECIFIC IN ACKNOWLEDGING CLRNCS USING OUR FULL CALL SIGN AND CLRNC. IN THIS OCCURRENCE, I THOUGHT A CONFLICT WAS ABOUT TO OCCUR DUE TO THE XMISSION OF 'CLRED FOR AN IMMEDIATE' TKOF THAT TO EXPEDITE, I SHORTENED MY REPLY TO X, DXY ROLLING INSTEAD OF ACR X DXY CLRED FOR TKOF FROM 32L. THE BEST LESSON LEARNED IS NEVER GET CAUGHT UP IN GO, GO STATE OF MIND AND ALWAYS SIT BACK AND TAKE YOUR TIME TO BE SURE YOU HEAR WHAT YOU ARE SUPPOSED TO HEAR.

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.