Narrative:

Just after takeoff at ord both pilots heard and acknowledged a frequency change to departure control. Departure control reported radar contact then told us to return to tower frequency. Tower told us to turn to a 180 degree heading and then switched us back to departure control. Evidently I switched to departure early. Departure control said there was no conflict, but was not sure if there was a problem with tower. This is additional information to previous report. The tower controller was working 2 runways 22L and 27L. I probably heard him switch the runway 22L traffic to departure and assumed it was our flight departing runway 27L.

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Original NASA ASRS Text

Title: AN ACR B757 FLC CHANGED TO DEP CTL FREQ BEFORE THEY SHOULD HAVE. THE DEP CTLR SENT THEM BACK TO THE TWR FREQ.

Narrative: JUST AFTER TKOF AT ORD BOTH PLTS HEARD AND ACKNOWLEDGED A FREQ CHANGE TO DEP CTL. DEP CTL RPTED RADAR CONTACT THEN TOLD US TO RETURN TO TWR FREQ. TWR TOLD US TO TURN TO A 180 DEG HDG AND THEN SWITCHED US BACK TO DEP CTL. EVIDENTLY I SWITCHED TO DEP EARLY. DEP CTL SAID THERE WAS NO CONFLICT, BUT WAS NOT SURE IF THERE WAS A PROB WITH TWR. THIS IS ADDITIONAL INFO TO PREVIOUS RPT. THE TWR CTLR WAS WORKING 2 RWYS 22L AND 27L. I PROBABLY HEARD HIM SWITCH THE RWY 22L TFC TO DEP AND ASSUMED IT WAS OUR FLT DEPARTING RWY 27L.

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.