Narrative:

Filed for IFR out of FD77 through st petersburg, fl. At airport, picked up clearance by phone, with a clearance time of XA15 to XA25. Fueled the aircraft, taxi, run-up, etc. Checked time (had set watch time at home). ATC didn't confirm any times with me when I picked up clearance. Took off per my watch XA15 VFR. Clearance read climb to 2000 ft on heading 070 degrees. After takeoff on runway 27, called tpa approach on 119.9. Didn't hear any reply. Called again. Controller said he had told me to stand by, and said, I departed too early. He said time was XA13. My watch showed XA17Z at that time. I was in VFR WX. Controller called back and again, went over the time clearance requirements. I said my watch showed XA17Z at my first call. I later checked my watch time with ZJX. My watch was 1 min 30 seconds fast. I don't know the time window, but it is hard to believe that ATC would have an aircraft in the area with a 1 min 30 second time, distance between one and the other. I believe this controller was overloaded and spent too much time on the radio going over something, and could have used the time to help lower his workload. I believe this could be fixed by having ATC confirm the time when you get the clearance by phone.

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Original NASA ASRS Text

Title: DEP FROM FD77, M20P PLT EXECUTES AN ATC CLRNC ONLY TO BE SCOLDED BY TPA APCH BECAUSE THE PLT DEPARTED PRIOR TO CLRNC RELEASE TIME. PLT ALLEGES NO 'TIME HACK' WAS ISSUED. PLT'S WATCH WAS 1 MIN, 30 SECONDS FAST.

Narrative: FILED FOR IFR OUT OF FD77 THROUGH ST PETERSBURG, FL. AT ARPT, PICKED UP CLRNC BY PHONE, WITH A CLRNC TIME OF XA15 TO XA25. FUELED THE ACFT, TAXI, RUN-UP, ETC. CHKED TIME (HAD SET WATCH TIME AT HOME). ATC DIDN'T CONFIRM ANY TIMES WITH ME WHEN I PICKED UP CLRNC. TOOK OFF PER MY WATCH XA15 VFR. CLRNC READ CLB TO 2000 FT ON HDG 070 DEGS. AFTER TKOF ON RWY 27, CALLED TPA APCH ON 119.9. DIDN'T HEAR ANY REPLY. CALLED AGAIN. CTLR SAID HE HAD TOLD ME TO STAND BY, AND SAID, I DEPARTED TOO EARLY. HE SAID TIME WAS XA13. MY WATCH SHOWED XA17Z AT THAT TIME. I WAS IN VFR WX. CTLR CALLED BACK AND AGAIN, WENT OVER THE TIME CLRNC REQUIREMENTS. I SAID MY WATCH SHOWED XA17Z AT MY FIRST CALL. I LATER CHKED MY WATCH TIME WITH ZJX. MY WATCH WAS 1 MIN 30 SECONDS FAST. I DON'T KNOW THE TIME WINDOW, BUT IT IS HARD TO BELIEVE THAT ATC WOULD HAVE AN ACFT IN THE AREA WITH A 1 MIN 30 SECOND TIME, DISTANCE BTWN ONE AND THE OTHER. I BELIEVE THIS CTLR WAS OVERLOADED AND SPENT TOO MUCH TIME ON THE RADIO GOING OVER SOMETHING, AND COULD HAVE USED THE TIME TO HELP LOWER HIS WORKLOAD. I BELIEVE THIS COULD BE FIXED BY HAVING ATC CONFIRM THE TIME WHEN YOU GET THE CLRNC BY PHONE.

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.