Narrative:

We approached the dca area along with numerous other aircraft via radar vectors during a period of heavy thunderstorm activity. It was apparent that the controller had too many aircraft in his sector for the existing WX conditions. There were many requests for deviations for WX. Our problem occurred when we were asked to turn right about 30 degrees. This heading would have put us into a thunderstorm that was a mi off the right side of the aircraft. The radar return was solid red with spots of magenta indicating heavy turbulence. We refused the vector due to the WX. The controller, after much rhetoric, said we would have to declare a WX emergency if we weren't going to turn. The emergency was declared and we continued. It is apparent that too many airplanes were in the area for existing conditions. Holding patterns should have been established before conditions were allowed to deteriorate this far. Supplemental information from acn 251204: when he became further demanding and forceful in his commands to fly certain assigned headings and altitudes which would place the flight in a safety compromising situation, I declared a WX emergency to avoid any harm to the passenger or crew. It is not known whether or not a traffic conflict existed as a result of the deviations.

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Original NASA ASRS Text

Title: HDG TRACK DEV IN NON ADHERENCE TO ATC CLRNC INSTRUCTION DURING RADAR VECTORING IN TSTM ACTIVITY.

Narrative: WE APCHED THE DCA AREA ALONG WITH NUMEROUS OTHER ACFT VIA RADAR VECTORS DURING A PERIOD OF HVY TSTM ACTIVITY. IT WAS APPARENT THAT THE CTLR HAD TOO MANY ACFT IN HIS SECTOR FOR THE EXISTING WX CONDITIONS. THERE WERE MANY REQUESTS FOR DEVS FOR WX. OUR PROB OCCURRED WHEN WE WERE ASKED TO TURN R ABOUT 30 DEGS. THIS HDG WOULD HAVE PUT US INTO A TSTM THAT WAS A MI OFF THE R SIDE OF THE ACFT. THE RADAR RETURN WAS SOLID RED WITH SPOTS OF MAGENTA INDICATING HVY TURB. WE REFUSED THE VECTOR DUE TO THE WX. THE CTLR, AFTER MUCH RHETORIC, SAID WE WOULD HAVE TO DECLARE A WX EMER IF WE WEREN'T GOING TO TURN. THE EMER WAS DECLARED AND WE CONTINUED. IT IS APPARENT THAT TOO MANY AIRPLANES WERE IN THE AREA FOR EXISTING CONDITIONS. HOLDING PATTERNS SHOULD HAVE BEEN ESTABLISHED BEFORE CONDITIONS WERE ALLOWED TO DETERIORATE THIS FAR. SUPPLEMENTAL INFORMATION FROM ACN 251204: WHEN HE BECAME FURTHER DEMANDING AND FORCEFUL IN HIS COMMANDS TO FLY CERTAIN ASSIGNED HDGS AND ALTS WHICH WOULD PLACE THE FLT IN A SAFETY COMPROMISING SIT, I DECLARED A WX EMER TO AVOID ANY HARM TO THE PAX OR CREW. IT IS NOT KNOWN WHETHER OR NOT A TFC CONFLICT EXISTED AS A RESULT OF THE DEVS.

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.