Narrative:

Line of thunderstorms across jet route A-300 at position elwod. WX was much more severe to west of elwod. Chose eastern deviation and requested permission to deviate 20 NM east of course via HF radio. Permission was denied by ATC. I exercised captain's emergency authority/authorized and deviated 20 NM east, as planned, at 20 NM north of elwod. I made a broadcast on VHF guard giving my call sign, position, altitude and deviation distance. ATC was also informed via HF. We did not see nor did we pick up any other aircraft on our TCASII, nor was there any response to my VHF guard call (TCASII range was set to 40 NM). Terminated deviation at 15 NM south of elwod. Following this return to course, made a call to ATC and another transmission on guard (stating this fact). Corrective action: need direct contact with ATC on HF, not through preset arinc 'middleman.'

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Original NASA ASRS Text

Title: FLC OF WDB ACR DEVIATED AROUND WX AFTER DENIAL BY ATC FOR TRACK DEV.

Narrative: LINE OF TSTMS ACROSS JET RTE A-300 AT POS ELWOD. WX WAS MUCH MORE SEVERE TO W OF ELWOD. CHOSE EASTERN DEV AND REQUESTED PERMISSION TO DEVIATE 20 NM E OF COURSE VIA HF RADIO. PERMISSION WAS DENIED BY ATC. I EXERCISED CAPT'S EMER AUTH AND DEVIATED 20 NM E, AS PLANNED, AT 20 NM N OF ELWOD. I MADE A BROADCAST ON VHF GUARD GIVING MY CALL SIGN, POS, ALT AND DEV DISTANCE. ATC WAS ALSO INFORMED VIA HF. WE DID NOT SEE NOR DID WE PICK UP ANY OTHER ACFT ON OUR TCASII, NOR WAS THERE ANY RESPONSE TO MY VHF GUARD CALL (TCASII RANGE WAS SET TO 40 NM). TERMINATED DEV AT 15 NM S OF ELWOD. FOLLOWING THIS RETURN TO COURSE, MADE A CALL TO ATC AND ANOTHER XMISSION ON GUARD (STATING THIS FACT). CORRECTIVE ACTION: NEED DIRECT CONTACT WITH ATC ON HF, NOT THROUGH PRESET ARINC 'MIDDLEMAN.'

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.