Narrative:

I was giving instruction to a student on IFR procedures. We had obtained an IFR clearance to sba from smo and executed the ILS 7 approach to a landing, intending to taxi back, get a return IFR clearance back to smo, and depart. After touching down, I told my student essentially, 'if they don't tell us what to do, just make a right turnoff at the next taxiway.' at this point, we were still on frequency with sba tower. The aircraft rolled past taxiway F as tower instructed us to 'contact ground,' even though we were still on runway 7 rolling out, nor were we told any preferred turnoff direction. My student immediately switched to ground control frequency and said we were 'with them' (poor radio technique), as the aircraft approached runway 15R's intersection. At this time the student began a right turn onto runway 15R, still fumbling with the radio, and I realized he intended to turn off onto runway 15R, probably mistaking it for a taxiway. I stood on the brakes and began to take control of the plane, intending to swing it back onto runway 7, as the ground controller notified us that we were 'about to taxi onto an active runway without permission.' I got the plane stopped and radioed the controller that we were 'stopping here, and how would you like us to proceed.

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Original NASA ASRS Text

Title: A C172 INSTRUCTOR AND STUDENT, AFTER LNDG AT SBA, EXITED THE RWY ONTO AN INTERSECTING RWY WITHOUT A CLRNC.

Narrative: I WAS GIVING INSTRUCTION TO A STUDENT ON IFR PROCS. WE HAD OBTAINED AN IFR CLRNC TO SBA FROM SMO AND EXECUTED THE ILS 7 APCH TO A LNDG, INTENDING TO TAXI BACK, GET A RETURN IFR CLRNC BACK TO SMO, AND DEPART. AFTER TOUCHING DOWN, I TOLD MY STUDENT ESSENTIALLY, 'IF THEY DON'T TELL US WHAT TO DO, JUST MAKE A R TURNOFF AT THE NEXT TXWY.' AT THIS POINT, WE WERE STILL ON FREQ WITH SBA TWR. THE ACFT ROLLED PAST TXWY F AS TWR INSTRUCTED US TO 'CONTACT GND,' EVEN THOUGH WE WERE STILL ON RWY 7 ROLLING OUT, NOR WERE WE TOLD ANY PREFERRED TURNOFF DIRECTION. MY STUDENT IMMEDIATELY SWITCHED TO GND CTL FREQ AND SAID WE WERE 'WITH THEM' (POOR RADIO TECHNIQUE), AS THE ACFT APCHED RWY 15R'S INTXN. AT THIS TIME THE STUDENT BEGAN A R TURN ONTO RWY 15R, STILL FUMBLING WITH THE RADIO, AND I REALIZED HE INTENDED TO TURN OFF ONTO RWY 15R, PROBABLY MISTAKING IT FOR A TXWY. I STOOD ON THE BRAKES AND BEGAN TO TAKE CTL OF THE PLANE, INTENDING TO SWING IT BACK ONTO RWY 7, AS THE GND CTLR NOTIFIED US THAT WE WERE 'ABOUT TO TAXI ONTO AN ACTIVE RWY WITHOUT PERMISSION.' I GOT THE PLANE STOPPED AND RADIOED THE CTLR THAT WE WERE 'STOPPING HERE, AND HOW WOULD YOU LIKE US TO PROCEED.

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.