Narrative:

After takeoff we accepted a 360 degree turn. Reaching 360 degree heading we saw that clearance between 2 convective cells would not be sufficient and asked for further turn to 030 degrees. Departure controller said 'unable, traffic at 11000 ft crossing above you.' we told him of build-ups at our 12 O'clock position and said we needed a turn to at least 025 degrees. He replied 'unable.' I then told him we had to have the turn. He asked if I was declaring an emergency. I replied 'affirmative' and asked him to 'clear the airspace to our right.' no further incident.

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Original NASA ASRS Text

Title: REVISED HDG ISSUED TO ACR MLG AFTER FLC DECLARES AN EMER DUE TO TSTM ACTIVITY IN PROX OF ACFT.

Narrative: AFTER TKOF WE ACCEPTED A 360 DEG TURN. REACHING 360 DEG HDG WE SAW THAT CLRNC BTWN 2 CONVECTIVE CELLS WOULD NOT BE SUFFICIENT AND ASKED FOR FURTHER TURN TO 030 DEGS. DEP CTLR SAID 'UNABLE, TFC AT 11000 FT XING ABOVE YOU.' WE TOLD HIM OF BUILD-UPS AT OUR 12 O'CLOCK POS AND SAID WE NEEDED A TURN TO AT LEAST 025 DEGS. HE REPLIED 'UNABLE.' I THEN TOLD HIM WE HAD TO HAVE THE TURN. HE ASKED IF I WAS DECLARING AN EMER. I REPLIED 'AFFIRMATIVE' AND ASKED HIM TO 'CLR THE AIRSPACE TO OUR R.' NO FURTHER INCIDENT.

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.