Narrative:

On the ground at unv (state college, PA), the first officer obtained our clearance from center while I monitored unicom. He briefed the clearance as follows for departure: 'runway heading, 4000 ft.' we departed and continued climb up to 9000 ft on runway heading of 240 degrees. During the climb we made radio contact with center on 2-3 occasions. Each time, I ended my response with 'runway heading' (to bring to center's attention that we were on runway heading still). At approximately 5 mins after takeoff, center advised that we were to proceed direct to hyper intersection and that we were never cleared to fly runway heading. Hence, our route of flight took us into another sector's airspace. The misunderstanding of the initial clearance by the first officer was the beginning of the problem. The subsequent 2 or 3 radio xmissions with center after departure compounded the problem. Center was working at least 2 frequencys and had difficulty affirming our response that we were climbing to 9000 ft, due to frequency congestion. After every response, I ended them with 'runway heading' (in order to state our flight track and reconfirm our clearance). Without hearing a corrective clearance from center, we continued on runway heading. As captain, I could have been more assertive with center regarding our clearance of runway heading. The clearance relayed to me from the first officer seemed a little out of the ordinary, however, over the sequence of events that transpired, there was no reason to question it.

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Original NASA ASRS Text

Title: A JS41 CREW MISINTERPED DEP CLRNC AND MAINTAINED RWY HDG.

Narrative: ON THE GND AT UNV (STATE COLLEGE, PA), THE FO OBTAINED OUR CLRNC FROM CTR WHILE I MONITORED UNICOM. HE BRIEFED THE CLRNC AS FOLLOWS FOR DEP: 'RWY HDG, 4000 FT.' WE DEPARTED AND CONTINUED CLB UP TO 9000 FT ON RWY HDG OF 240 DEGS. DURING THE CLB WE MADE RADIO CONTACT WITH CTR ON 2-3 OCCASIONS. EACH TIME, I ENDED MY RESPONSE WITH 'RWY HDG' (TO BRING TO CTR'S ATTN THAT WE WERE ON RWY HDG STILL). AT APPROX 5 MINS AFTER TKOF, CTR ADVISED THAT WE WERE TO PROCEED DIRECT TO HYPER INTXN AND THAT WE WERE NEVER CLRED TO FLY RWY HDG. HENCE, OUR RTE OF FLT TOOK US INTO ANOTHER SECTOR'S AIRSPACE. THE MISUNDERSTANDING OF THE INITIAL CLRNC BY THE FO WAS THE BEGINNING OF THE PROB. THE SUBSEQUENT 2 OR 3 RADIO XMISSIONS WITH CTR AFTER DEP COMPOUNDED THE PROB. CTR WAS WORKING AT LEAST 2 FREQS AND HAD DIFFICULTY AFFIRMING OUR RESPONSE THAT WE WERE CLBING TO 9000 FT, DUE TO FREQ CONGESTION. AFTER EVERY RESPONSE, I ENDED THEM WITH 'RWY HDG' (IN ORDER TO STATE OUR FLT TRACK AND RECONFIRM OUR CLRNC). WITHOUT HEARING A CORRECTIVE CLRNC FROM CTR, WE CONTINUED ON RWY HDG. AS CAPT, I COULD HAVE BEEN MORE ASSERTIVE WITH CTR REGARDING OUR CLRNC OF RWY HDG. THE CLRNC RELAYED TO ME FROM THE FO SEEMED A LITTLE OUT OF THE ORDINARY, HOWEVER, OVER THE SEQUENCE OF EVENTS THAT TRANSPIRED, THERE WAS NO REASON TO QUESTION IT.

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.