Narrative:

First officer and I were cleared to taxi in position and hold on runway 18L at tpa due to traffic taking off on runway 18R. Our clearance was 310 degrees on heading up to 1600 ft, expect 16000 ft, departure 125.3. We were cleared for departure from tower. Climbing up to 500 ft MSL, 180 degrees on heading, I then tried to confirm our assigned heading with tower, but my transmission was blocked. Climbing through 500 ft MSL, I tried to confirm heading again. Tpa tower replied, 'air carrier X 310 degree heading, transmission blocked, 3000 ft departure 125.3.' I answered, 'roger.' my first officer began our turn to 310 degree heading, I switched to departure (125.3). I replied, 'air carrier X checking in 310 degrees on heading.' tpa departure said, 'air carrier X your altitude is 2600 ft MSL, you were cleared to 1600 ft, that's ok, now climb to 4000 ft.' tpa departure then said, 'air carrier X what was your assigned altitude?' I replied, '1600 ft, but we were cleared to 3000 ft.' I explained that our transmission was blocked with tower and my first officer and I heard clearance to 3000 ft prior to switching to departure. There was no loss in aircraft separation, no aircraft deviation. We had traffic off runway 18R in sight, and no TCASII advisories.

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Original NASA ASRS Text

Title: CREW ON BE02 RECEIVED ATC CLRNC BEFORE TKOF AT TPA WHICH INCLUDED MAINTAIN 1600 FT, EXPECT 16000 FT. WHEN AIRBORNE, THE CAPT ASKED THE TWR TO CONFIRM ASSIGNED ALT AND THROUGH A BLOCKED XMISSION HEARD 3000 FT.

Narrative: FO AND I WERE CLRED TO TAXI IN POS AND HOLD ON RWY 18L AT TPA DUE TO TFC TAKING OFF ON RWY 18R. OUR CLRNC WAS 310 DEGS ON HDG UP TO 1600 FT, EXPECT 16000 FT, DEP 125.3. WE WERE CLRED FOR DEP FROM TWR. CLBING UP TO 500 FT MSL, 180 DEGS ON HDG, I THEN TRIED TO CONFIRM OUR ASSIGNED HDG WITH TWR, BUT MY XMISSION WAS BLOCKED. CLBING THROUGH 500 FT MSL, I TRIED TO CONFIRM HDG AGAIN. TPA TWR REPLIED, 'ACR X 310 DEG HDG, XMISSION BLOCKED, 3000 FT DEP 125.3.' I ANSWERED, 'ROGER.' MY FO BEGAN OUR TURN TO 310 DEG HDG, I SWITCHED TO DEP (125.3). I REPLIED, 'ACR X CHKING IN 310 DEGS ON HDG.' TPA DEP SAID, 'ACR X YOUR ALT IS 2600 FT MSL, YOU WERE CLRED TO 1600 FT, THAT'S OK, NOW CLB TO 4000 FT.' TPA DEP THEN SAID, 'ACR X WHAT WAS YOUR ASSIGNED ALT?' I REPLIED, '1600 FT, BUT WE WERE CLRED TO 3000 FT.' I EXPLAINED THAT OUR XMISSION WAS BLOCKED WITH TWR AND MY FO AND I HEARD CLRNC TO 3000 FT PRIOR TO SWITCHING TO DEP. THERE WAS NO LOSS IN ACFT SEPARATION, NO ACFT DEV. WE HAD TFC OFF RWY 18R IN SIGHT, AND NO TCASII ADVISORIES.

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.