Narrative:

We departed dtw for bos without obtaining a predep IFR clearance on ACARS. The flight was delayed and the clearance was not obtained in the normal sequence of predep events since the delay time was not known. When we were finally released to depart, the clearance was overlooked. Receiving the clearance over ACARS is a relatively passive activity as compared to receiving and copying it over the radio. I think this has had the effect of making it easier to forget. We realized shortly after takeoff that we hadn't obtained a clearance when the copilot noticed that there was no code set in the transponder. Evidently the clearance had been issued since the controllers knew of it, we had failed to pick it up.

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Original NASA ASRS Text

Title: FLC FAILED TO RECEIVE ATC CLRNC ON ACARS AND DIDN'T RECEIVE IFR CLRNC UNTIL AIRBORNE.

Narrative: WE DEPARTED DTW FOR BOS WITHOUT OBTAINING A PREDEP IFR CLRNC ON ACARS. THE FLT WAS DELAYED AND THE CLRNC WAS NOT OBTAINED IN THE NORMAL SEQUENCE OF PREDEP EVENTS SINCE THE DELAY TIME WAS NOT KNOWN. WHEN WE WERE FINALLY RELEASED TO DEPART, THE CLRNC WAS OVERLOOKED. RECEIVING THE CLRNC OVER ACARS IS A RELATIVELY PASSIVE ACTIVITY AS COMPARED TO RECEIVING AND COPYING IT OVER THE RADIO. I THINK THIS HAS HAD THE EFFECT OF MAKING IT EASIER TO FORGET. WE REALIZED SHORTLY AFTER TKOF THAT WE HADN'T OBTAINED A CLRNC WHEN THE COPLT NOTICED THAT THERE WAS NO CODE SET IN THE XPONDER. EVIDENTLY THE CLRNC HAD BEEN ISSUED SINCE THE CTLRS KNEW OF IT, WE HAD FAILED TO PICK IT UP.

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.