Narrative:

After landing at mkc, we refueled the aircraft and continued other duties separately, so as to expedite our departure from mkc to cos and back to dma. Upon getting ready to reboard the aircraft, I asked the other pilot on the trip, if he had filed a flight plan, to which he stated, we would depart VFR. I believed we were going to go IFR, however I suspected he knew something I didn't. We started and taxied, ground asked if we had a flight plan. We advised them we were departing VFR in VFR conditions, to which they acknowledged in a surprised tone, to taxi to runway 1 and contact tower when ready. We were cleared for takeoff with instructions to make a left turn on course. We did as instructed. I continued to navigation in VFR conditions, looking for other traffic climbing out, while the other pilot handled the radios. I heard him ask tower for a frequency change. When he contacted this frequency, they immediately instructed us to change to another frequency. When we contacted this frequency the controller asked our position, gave us a traffic callout and a squawk change. After we were clear of traffic, we climbed to 16500 ft with flight following, at which time the controller gave us a phone number to call upon our arrival at cos. We continued our flight with flight following to cos. Upon calling the number in kansas city, we were informed we had encroached into class B airspace. At no time was I aware we had entered into controled airspace without clearance until arriving in cos. Looking back on this I could have queried the other pilot for more information, queried tower as to the surprised tone in their voice when we requested VFR, tower could have notified us of the closeness of the airspace.

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Original NASA ASRS Text

Title: GOV PLTS ENTER CLASS B AIRSPACE WITHOUT CLRNC AFTER DEPARTING AN UNDERLYING ARPT.

Narrative: AFTER LNDG AT MKC, WE REFUELED THE ACFT AND CONTINUED OTHER DUTIES SEPARATELY, SO AS TO EXPEDITE OUR DEP FROM MKC TO COS AND BACK TO DMA. UPON GETTING READY TO REBOARD THE ACFT, I ASKED THE OTHER PLT ON THE TRIP, IF HE HAD FILED A FLT PLAN, TO WHICH HE STATED, WE WOULD DEPART VFR. I BELIEVED WE WERE GOING TO GO IFR, HOWEVER I SUSPECTED HE KNEW SOMETHING I DIDN'T. WE STARTED AND TAXIED, GND ASKED IF WE HAD A FLT PLAN. WE ADVISED THEM WE WERE DEPARTING VFR IN VFR CONDITIONS, TO WHICH THEY ACKNOWLEDGED IN A SURPRISED TONE, TO TAXI TO RWY 1 AND CONTACT TWR WHEN READY. WE WERE CLRED FOR TKOF WITH INSTRUCTIONS TO MAKE A L TURN ON COURSE. WE DID AS INSTRUCTED. I CONTINUED TO NAV IN VFR CONDITIONS, LOOKING FOR OTHER TFC CLBING OUT, WHILE THE OTHER PLT HANDLED THE RADIOS. I HEARD HIM ASK TWR FOR A FREQ CHANGE. WHEN HE CONTACTED THIS FREQ, THEY IMMEDIATELY INSTRUCTED US TO CHANGE TO ANOTHER FREQ. WHEN WE CONTACTED THIS FREQ THE CTLR ASKED OUR POS, GAVE US A TFC CALLOUT AND A SQUAWK CHANGE. AFTER WE WERE CLR OF TFC, WE CLBED TO 16500 FT WITH FLT FOLLOWING, AT WHICH TIME THE CTLR GAVE US A PHONE NUMBER TO CALL UPON OUR ARR AT COS. WE CONTINUED OUR FLT WITH FLT FOLLOWING TO COS. UPON CALLING THE NUMBER IN KANSAS CITY, WE WERE INFORMED WE HAD ENCROACHED INTO CLASS B AIRSPACE. AT NO TIME WAS I AWARE WE HAD ENTERED INTO CTLED AIRSPACE WITHOUT CLRNC UNTIL ARRIVING IN COS. LOOKING BACK ON THIS I COULD HAVE QUERIED THE OTHER PLT FOR MORE INFO, QUERIED TWR AS TO THE SURPRISED TONE IN THEIR VOICE WHEN WE REQUESTED VFR, TWR COULD HAVE NOTIFIED US OF THE CLOSENESS OF THE AIRSPACE.

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.