DC9 crew was required to declare an emergency to avoid convective WX shown on radar.

Attributes
ACN	457867
Time
Date	199912
Day	Mon
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : phl.airport
State Reference	PA
Altitude	msl single value : 8000
Environment
Flight Conditions	IMC
Weather Elements	Rain Turbulence
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : phl.tracon tower : sjc.tower
Operator	common carrier : air carrier
Make Model Name	DC-9 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Flight Phase	climbout : intermediate altitude
Route In Use	departure : on vectors
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp
Experience	flight time last 90 days : 200 flight time total : 6900 flight time type : 760
ASRS Report	457867
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Events
Anomaly	inflight encounter : turbulence inflight encounter : weather non adherence : clearance other anomaly other other spatial deviation
Independent Detector	other controllera other flight crewa other flight crewb
Resolutory Action	flight crew : declared emergency none taken : anomaly accepted
Supplementary
Problem Areas	Airspace Structure Weather Flight Crew Human Performance FAA ATC Human Performance
Primary Problem	Weather
Air Traffic Incident	Inter Facility Coordination Failure
Situations
ATC Facility	procedure or policy : phl.tracon

Narrative:

Upon departure from phl runway 9, received several radar vectors. While on a 360 degree heading, ATC instructed a left turn to 310 degrees. Due to rainshower on radar, we advised ATC that we needed 360 degrees for 10 mi due to WX. ATC replied he needed 310 degrees immediately. Captain informed ATC he would not turn left due to WX. We were told to 'squawk emergency,' that we would be flying into washington approach traffic and to use caution. After a couple mins, we were able to accept a left turn, which brought us back into phl departure airspace. We were instructed to resume previous squawk code and subsequently continued to destination without further conflict.

Original NASA ASRS Text

Title: DC9 CREW WAS REQUIRED TO DECLARE AN EMER TO AVOID CONVECTIVE WX SHOWN ON RADAR.

Narrative: UPON DEP FROM PHL RWY 9, RECEIVED SEVERAL RADAR VECTORS. WHILE ON A 360 DEG HDG, ATC INSTRUCTED A L TURN TO 310 DEGS. DUE TO RAINSHOWER ON RADAR, WE ADVISED ATC THAT WE NEEDED 360 DEGS FOR 10 MI DUE TO WX. ATC REPLIED HE NEEDED 310 DEGS IMMEDIATELY. CAPT INFORMED ATC HE WOULD NOT TURN L DUE TO WX. WE WERE TOLD TO 'SQUAWK EMER,' THAT WE WOULD BE FLYING INTO WASHINGTON APCH TFC AND TO USE CAUTION. AFTER A COUPLE MINS, WE WERE ABLE TO ACCEPT A L TURN, WHICH BROUGHT US BACK INTO PHL DEP AIRSPACE. WE WERE INSTRUCTED TO RESUME PREVIOUS SQUAWK CODE AND SUBSEQUENTLY CONTINUED TO DEST WITHOUT FURTHER CONFLICT.

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.