Narrative:

Ready to depart fft on IFR flight plan at 45 local with 50 clearance void time from lex approach control. Had completed engine run- up, navigation aids tuned with 1 communication radio on lex approach control and other on fft (capital city's) unicom -- all set to go with 2 aircraft in front and others on base and downwind. Things got a bit tight and I began to wonder if I would make my departure time. Both aircraft in front had departed with an intervening landing. When I was #1, I asked aircraft on downwind to extend his base so I could make my time. I didn't expect an answer because there was a lot of radio traffic. As a landing aircraft passed in front of me, I took a quick look, saw no one and announced 'taxiing into position and holding for rollout traffic' (actually he was touch and go). As he broke ground, I advanced the throttle and heard an anguished voice saying something about being on 1/2 mi final, or short final. I was committed to the takeoff at that point. After I had broken ground I apologized to the aircraft behind and remarked that I thought he had heard my request to extend his base. The response -- 'someone call lex approach control?þ I had forgotten to turn off the other receiver and switch transmitters!! All my previous xmissions had gone to lex approach control!! It's a great convenience to have 2 radio transmitters, but I allowed the anxiety of making a 'clearance void time' cut me out of a habit developed long ago to keep only 1 (radio transmitter) on at a time to preclude what had just happened from happening. The habit was/is good if I can just keep to it!

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Original NASA ASRS Text

Title: PVT PLT MADE TKOF IN FRONT OF ANOTHER ACFT ON SHORT FINAL AT AN UNCTLED ARPT.

Narrative: READY TO DEPART FFT ON IFR FLT PLAN AT 45 LCL WITH 50 CLRNC VOID TIME FROM LEX APCH CTL. HAD COMPLETED ENG RUN- UP, NAV AIDS TUNED WITH 1 COM RADIO ON LEX APCH CTL AND OTHER ON FFT (CAPITAL CITY'S) UNICOM -- ALL SET TO GO WITH 2 ACFT IN FRONT AND OTHERS ON BASE AND DOWNWIND. THINGS GOT A BIT TIGHT AND I BEGAN TO WONDER IF I WOULD MAKE MY DEP TIME. BOTH ACFT IN FRONT HAD DEPARTED WITH AN INTERVENING LNDG. WHEN I WAS #1, I ASKED ACFT ON DOWNWIND TO EXTEND HIS BASE SO I COULD MAKE MY TIME. I DIDN'T EXPECT AN ANSWER BECAUSE THERE WAS A LOT OF RADIO TFC. AS A LNDG ACFT PASSED IN FRONT OF ME, I TOOK A QUICK LOOK, SAW NO ONE AND ANNOUNCED 'TAXIING INTO POS AND HOLDING FOR ROLLOUT TRAFFIC' (ACTUALLY HE WAS TOUCH AND GO). AS HE BROKE GND, I ADVANCED THE THROTTLE AND HEARD AN ANGUISHED VOICE SAYING SOMETHING ABOUT BEING ON 1/2 MI FINAL, OR SHORT FINAL. I WAS COMMITTED TO THE TKOF AT THAT POINT. AFTER I HAD BROKEN GND I APOLOGIZED TO THE ACFT BEHIND AND REMARKED THAT I THOUGHT HE HAD HEARD MY REQUEST TO EXTEND HIS BASE. THE RESPONSE -- 'SOMEONE CALL LEX APCH CTL?þ I HAD FORGOTTEN TO TURN OFF THE OTHER RECEIVER AND SWITCH XMITTERS!! ALL MY PREVIOUS XMISSIONS HAD GONE TO LEX APCH CTL!! IT'S A GREAT CONVENIENCE TO HAVE 2 RADIO XMITTERS, BUT I ALLOWED THE ANXIETY OF MAKING A 'CLRNC VOID TIME' CUT ME OUT OF A HABIT DEVELOPED LONG AGO TO KEEP ONLY 1 (RADIO XMITTER) ON AT A TIME TO PRECLUDE WHAT HAD JUST HAPPENED FROM HAPPENING. THE HABIT WAS/IS GOOD IF I CAN JUST KEEP TO IT!

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.