Narrative:

Myself and another instructor pilot were flying a PA44 for currency. I was at the controls and the other pilot was on the radio. I am not very familiar with this aircraft and I had a lot on my mind that day. We were cleared into position and hold. The other pilot read back the clearance which I didn't hear because of a separate volume control knob that I have that was turned down. In the airplanes I had been flying recently, there is only 1 volume control knob. I crossed the hold line and proceeded with the takeoff roll. I accelerated to about 35 KTS and covered about 1000 ft of runway before I saw a DC4 crossing downfield just as the tower was telling us to stop. I brought the airplane to a stop. We then received a takeoff clearance after the DC4 crossed the runway. We departed.

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Original NASA ASRS Text

Title: PA44 PLT FAILED TO HOLD IN POS FOR TKOF AND STARTED TKOF ROLL WHEN A DC4 WAS TAXIING ACROSS THE RWY IN FRONT OF HIM.

Narrative: MYSELF AND ANOTHER INSTRUCTOR PLT WERE FLYING A PA44 FOR CURRENCY. I WAS AT THE CTLS AND THE OTHER PLT WAS ON THE RADIO. I AM NOT VERY FAMILIAR WITH THIS ACFT AND I HAD A LOT ON MY MIND THAT DAY. WE WERE CLRED INTO POS AND HOLD. THE OTHER PLT READ BACK THE CLRNC WHICH I DIDN'T HEAR BECAUSE OF A SEPARATE VOLUME CTL KNOB THAT I HAVE THAT WAS TURNED DOWN. IN THE AIRPLANES I HAD BEEN FLYING RECENTLY, THERE IS ONLY 1 VOLUME CTL KNOB. I CROSSED THE HOLD LINE AND PROCEEDED WITH THE TKOF ROLL. I ACCELERATED TO ABOUT 35 KTS AND COVERED ABOUT 1000 FT OF RWY BEFORE I SAW A DC4 XING DOWNFIELD JUST AS THE TWR WAS TELLING US TO STOP. I BROUGHT THE AIRPLANE TO A STOP. WE THEN RECEIVED A TKOF CLRNC AFTER THE DC4 CROSSED THE RWY. WE DEPARTED.

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.