Narrative:

On departure from baltimore we were given a heading towards dulles that would have put us in the middle of a thunderstorm. We told the controller we couldn't fly this heading but 30 degrees right or 60 degrees left would work. He said his WX radar wasn't showing the WX and then said it didn't go out that far anyway. He then switched us over to another controller and told us to inform the new controller of our intentions. We switched to the new frequency and told the new controller we needed a different heading to avoid a thunderstorm and were told rather curtly that we were to turn to 180 degrees. I again informed the controller that 180 degrees would put us right in the middle of the WX. The controller then got rather angry and told us to turn immediately because of head on traffic. At the time we were climbing to 17000 ft. I then declared an emergency and turned to 150 degrees and told the controller we would hold just north of dulles (iad). The controller told us to maintain the 150 degree heading, and left us on that heading for 5-6 mins. We were then asked if we could make a left turn and proceed on our filed route. The first officer told the controller a left turn would work out great and we made our turn. The rest of the flight was without incident. During this entire incident, ATC appeared totally inflexible. The WX was at the most 10 NM across and was the only significant WX in over 100 NM in any direction.

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Original NASA ASRS Text

Title: THE FLC DECLARED AN EMER RATHER THAN ACCEPT A HDG THAT WOULD CARRY THEM INTO A TSTM.

Narrative: ON DEP FROM BALTIMORE WE WERE GIVEN A HDG TOWARDS DULLES THAT WOULD HAVE PUT US IN THE MIDDLE OF A TSTM. WE TOLD THE CTLR WE COULDN'T FLY THIS HDG BUT 30 DEGS R OR 60 DEGS L WOULD WORK. HE SAID HIS WX RADAR WASN'T SHOWING THE WX AND THEN SAID IT DIDN'T GO OUT THAT FAR ANYWAY. HE THEN SWITCHED US OVER TO ANOTHER CTLR AND TOLD US TO INFORM THE NEW CTLR OF OUR INTENTIONS. WE SWITCHED TO THE NEW FREQ AND TOLD THE NEW CTLR WE NEEDED A DIFFERENT HDG TO AVOID A TSTM AND WERE TOLD RATHER CURTLY THAT WE WERE TO TURN TO 180 DEGS. I AGAIN INFORMED THE CTLR THAT 180 DEGS WOULD PUT US RIGHT IN THE MIDDLE OF THE WX. THE CTLR THEN GOT RATHER ANGRY AND TOLD US TO TURN IMMEDIATELY BECAUSE OF HEAD ON TFC. AT THE TIME WE WERE CLBING TO 17000 FT. I THEN DECLARED AN EMER AND TURNED TO 150 DEGS AND TOLD THE CTLR WE WOULD HOLD JUST N OF DULLES (IAD). THE CTLR TOLD US TO MAINTAIN THE 150 DEG HDG, AND LEFT US ON THAT HDG FOR 5-6 MINS. WE WERE THEN ASKED IF WE COULD MAKE A L TURN AND PROCEED ON OUR FILED RTE. THE FO TOLD THE CTLR A L TURN WOULD WORK OUT GREAT AND WE MADE OUR TURN. THE REST OF THE FLT WAS WITHOUT INCIDENT. DURING THIS ENTIRE INCIDENT, ATC APPEARED TOTALLY INFLEXIBLE. THE WX WAS AT THE MOST 10 NM ACROSS AND WAS THE ONLY SIGNIFICANT WX IN OVER 100 NM IN ANY DIRECTION.

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.