Narrative:

On takeoff on runway 30L at stl, tower changed our takeoff intersection from the end to taxiway right and then to taxiway Q. We have charted takeoff performance for taxiway south and taxiway right but not taxiway Q. Rush hour traffic and busy radio conversations contributed in a takeoff from intersection Q. Supplemental information from acn 474841: tower asked at last min if we could accept an intersection departure. My first officer said we could. I asked him to doublechk the performance. He said he did and it was ok. On the return leg of the flight, I was verifying go around power in performance book for landing and noticed that there was no performance for the previous intersection departure. I decided not to say anything about it to my new first officer until we were on the ground so it wouldn't distract him on this approach and landing. However, it so preoccupied me, that during the before landing flow, I turned off the avionics bus switch, leaving us with basic mode only on the EFIS. Fortunately, it was VFR. Otherwise it might have turned into an emergency situation.

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Original NASA ASRS Text

Title: A J4100 FO RPT ON AN UNPLANNED AND UNAUTH INTXN TKOF FROM INTXN Q ON RWY 30L. THAT INCIDENT WAS LATER DISCOVERED BY THE CAPT WHO CITED IT AS A SOURCE FOR DISTR WHEN RETURNING TO STL, MO.

Narrative: ON TKOF ON RWY 30L AT STL, TWR CHANGED OUR TKOF INTXN FROM THE END TO TXWY R AND THEN TO TXWY Q. WE HAVE CHARTED TKOF PERFORMANCE FOR TXWY S AND TXWY R BUT NOT TXWY Q. RUSH HR TFC AND BUSY RADIO CONVERSATIONS CONTRIBUTED IN A TKOF FROM INTXN Q. SUPPLEMENTAL INFO FROM ACN 474841: TWR ASKED AT LAST MIN IF WE COULD ACCEPT AN INTXN DEP. MY FO SAID WE COULD. I ASKED HIM TO DOUBLECHK THE PERFORMANCE. HE SAID HE DID AND IT WAS OK. ON THE RETURN LEG OF THE FLT, I WAS VERIFYING GAR PWR IN PERFORMANCE BOOK FOR LNDG AND NOTICED THAT THERE WAS NO PERFORMANCE FOR THE PREVIOUS INTXN DEP. I DECIDED NOT TO SAY ANYTHING ABOUT IT TO MY NEW FO UNTIL WE WERE ON THE GND SO IT WOULDN'T DISTRACT HIM ON THIS APCH AND LNDG. HOWEVER, IT SO PREOCCUPIED ME, THAT DURING THE BEFORE LNDG FLOW, I TURNED OFF THE AVIONICS BUS SWITCH, LEAVING US WITH BASIC MODE ONLY ON THE EFIS. FORTUNATELY, IT WAS VFR. OTHERWISE IT MIGHT HAVE TURNED INTO AN EMER SIT.

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.