Narrative:

It was early morning and dark outside. Being ready for taxi, I listened for ATIS but didn't receive and then called tower for taxi but didn't get a response. I then checked my flight guide for tower operation hours and confirmed to opened at XA00. My watch is not always accurate and I was showing a few mins after XA00 and so assumed tower was not open and so taxied to an intersection of runway 11. Before takeoff, I broadcast over tower frequency that I was departing 11 northeast and then proceeded to takeoff. Upon reaching aspen, I radioed approach and again got no response. By this time it was light and upon making a check I discovered the volume on my radio was turned down. I assume now that this is the reason I didn't receive in grand junction. Although I have not confirmed this, I now believe that tower probably was open and heard my broadcasts. If this is true, my mistake was to assume tower was not open and to taxi and takeoff. Contributing to this incident is the fact that only 2 pilots fly this airplane and the radios are on a master switch. Normal procedures are to turn on the master and the radio volumes are preset. In this incident, the previous pilot had for some reason turned the volume down. At XA00 it was dark, and when I turned on the master, everything came on as normal and it did not occur to me to check the volume -- it was so close to XA00 it was my assumption tower was not open yet. And for that matter this still could be the case.

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Original NASA ASRS Text

Title: AN SMA PLT TOOK OFF WITH HIS RADIO VOLUME TURNED DOWN. THE TWR MAY HAVE NOT YET BEEN OPEN.

Narrative: IT WAS EARLY MORNING AND DARK OUTSIDE. BEING READY FOR TAXI, I LISTENED FOR ATIS BUT DIDN'T RECEIVE AND THEN CALLED TWR FOR TAXI BUT DIDN'T GET A RESPONSE. I THEN CHKED MY FLT GUIDE FOR TWR OP HRS AND CONFIRMED TO OPENED AT XA00. MY WATCH IS NOT ALWAYS ACCURATE AND I WAS SHOWING A FEW MINS AFTER XA00 AND SO ASSUMED TWR WAS NOT OPEN AND SO TAXIED TO AN INTXN OF RWY 11. BEFORE TKOF, I BROADCAST OVER TWR FREQ THAT I WAS DEPARTING 11 NE AND THEN PROCEEDED TO TKOF. UPON REACHING ASPEN, I RADIOED APCH AND AGAIN GOT NO RESPONSE. BY THIS TIME IT WAS LIGHT AND UPON MAKING A CHK I DISCOVERED THE VOLUME ON MY RADIO WAS TURNED DOWN. I ASSUME NOW THAT THIS IS THE REASON I DIDN'T RECEIVE IN GRAND JUNCTION. ALTHOUGH I HAVE NOT CONFIRMED THIS, I NOW BELIEVE THAT TWR PROBABLY WAS OPEN AND HEARD MY BROADCASTS. IF THIS IS TRUE, MY MISTAKE WAS TO ASSUME TWR WAS NOT OPEN AND TO TAXI AND TKOF. CONTRIBUTING TO THIS INCIDENT IS THE FACT THAT ONLY 2 PLTS FLY THIS AIRPLANE AND THE RADIOS ARE ON A MASTER SWITCH. NORMAL PROCS ARE TO TURN ON THE MASTER AND THE RADIO VOLUMES ARE PRESET. IN THIS INCIDENT, THE PREVIOUS PLT HAD FOR SOME REASON TURNED THE VOLUME DOWN. AT XA00 IT WAS DARK, AND WHEN I TURNED ON THE MASTER, EVERYTHING CAME ON AS NORMAL AND IT DID NOT OCCUR TO ME TO CHK THE VOLUME -- IT WAS SO CLOSE TO XA00 IT WAS MY ASSUMPTION TWR WAS NOT OPEN YET. AND FOR THAT MATTER THIS STILL COULD BE THE CASE.

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.