Narrative:

Both pilots arrived at the aircraft 35-40 mins before departure time. Preflight checks and checklists were run, and I inserted the flight plan into the FMS. I left the cockpit to brief the flight attendants, use the head, get a cup of coffee, and look for the pre departure clearance. Upon my return, the automated weight and balance paperwork arrived and there was a significant discrepancy in the planned and actual weight and I busied myself into investigating that. While the first officer made his radio calls, I talked to the ground crew. Pushback was made, and taxi clearance was obtained. There was a frequency problem on ground control and initial contact was difficult. Taxi was normal and all checklists were read. Before takeoff checklist was read and a normal takeoff was made. Upon reaching 1000 ft (clean-up altitude) the first officer suddenly announced to me that he had forgotten to get a clearance from clearance delivery. There was no pre departure clearance. He asked the departure controller the transponder code and he fired it right back with no hesitation, indicating that he might have known of the first officer's oversight. We asked for route verification with center and they read back our route as filed indicating that 'someone' opened our flight plan. Any time there has been a question or discrepancy in a flight plan, ground control has brought it to my attention. Why not this time. I don't know. Even though it is my responsibility, it is not my duty as PIC to obtain an IFR clearance, and not a function that I normally monitor (I will in the future). The probable cause to this, I think, was my assumption that the first officer got a clearance while I was absent from the cockpit, and his failure to do so, due to a long gap between trips.

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Original NASA ASRS Text

Title: ACR MLG DEPARTS WITHOUT HAVING RECEIVED ITS ATC CLRNC FROM CLRNC DELIVERY.

Narrative: BOTH PLTS ARRIVED AT THE ACFT 35-40 MINS BEFORE DEP TIME. PREFLT CHKS AND CHKLISTS WERE RUN, AND I INSERTED THE FLT PLAN INTO THE FMS. I LEFT THE COCKPIT TO BRIEF THE FLT ATTENDANTS, USE THE HEAD, GET A CUP OF COFFEE, AND LOOK FOR THE PDC. UPON MY RETURN, THE AUTOMATED WT AND BAL PAPERWORK ARRIVED AND THERE WAS A SIGNIFICANT DISCREPANCY IN THE PLANNED AND ACTUAL WT AND I BUSIED MYSELF INTO INVESTIGATING THAT. WHILE THE FO MADE HIS RADIO CALLS, I TALKED TO THE GND CREW. PUSHBACK WAS MADE, AND TAXI CLRNC WAS OBTAINED. THERE WAS A FREQ PROB ON GND CTL AND INITIAL CONTACT WAS DIFFICULT. TAXI WAS NORMAL AND ALL CHKLISTS WERE READ. BEFORE TKOF CHKLIST WAS READ AND A NORMAL TKOF WAS MADE. UPON REACHING 1000 FT (CLEAN-UP ALT) THE FO SUDDENLY ANNOUNCED TO ME THAT HE HAD FORGOTTEN TO GET A CLRNC FROM CLRNC DELIVERY. THERE WAS NO PDC. HE ASKED THE DEP CTLR THE XPONDER CODE AND HE FIRED IT RIGHT BACK WITH NO HESITATION, INDICATING THAT HE MIGHT HAVE KNOWN OF THE FO'S OVERSIGHT. WE ASKED FOR RTE VERIFICATION WITH CTR AND THEY READ BACK OUR RTE AS FILED INDICATING THAT 'SOMEONE' OPENED OUR FLT PLAN. ANY TIME THERE HAS BEEN A QUESTION OR DISCREPANCY IN A FLT PLAN, GND CTL HAS BROUGHT IT TO MY ATTN. WHY NOT THIS TIME. I DON'T KNOW. EVEN THOUGH IT IS MY RESPONSIBILITY, IT IS NOT MY DUTY AS PIC TO OBTAIN AN IFR CLRNC, AND NOT A FUNCTION THAT I NORMALLY MONITOR (I WILL IN THE FUTURE). THE PROBABLE CAUSE TO THIS, I THINK, WAS MY ASSUMPTION THAT THE FO GOT A CLRNC WHILE I WAS ABSENT FROM THE COCKPIT, AND HIS FAILURE TO DO SO, DUE TO A LONG GAP BTWN TRIPS.

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.