Flight crew deviated for WX when only given heading for deviation.

Attributes
ACN	440044
Time
Date	199906
Day	Mon
Local Time Of Day	1201 To 1800
Place
Locale Reference	navaid : gdm.vortac
State Reference	MA
Altitude	msl single value : 10000
Environment
Flight Conditions	VMC
Weather Elements	Thunderstorm
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zbw.artcc tower : cle.tower
Operator	common carrier : air carrier
Make Model Name	SF 340B
Operating Under FAR Part	Part 121
Flight Phase	cruise : level
Route In Use	enroute : direct enroute : on vectors
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : commercial pilot : multi engine pilot : instrument
Experience	flight time last 90 days : 180 flight time total : 2000 flight time type : 600
ASRS Report	440044
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Events
Anomaly	inflight encounter : weather non adherence : clearance other spatial deviation
Independent Detector	atc equipment other atc equipment : radar other controllera
Resolutory Action	controller : issued advisory flight crew : took precautionary avoidance action
Consequence	faa : reviewed incident with flight crew
Supplementary
Problem Areas	ATC Human Performance Flight Crew Human Performance Weather
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation Inter Facility Coordination Failure

Narrative:

We were assigned direct dsm VOR by controller. There were many build-ups in area, and we requested a 230 degree heading and up to 12000 ft to avoid WX. Controller gave us the 230 degree heading and we read it back. Controller said he would have higher in a few mins. Controller then cleared us to 12000 ft and turned us over to ZBW (134.7). We checked in with him and didn't tell him our heading for WX. The controller came on and told us that gdm was 20 degrees right, and we said that we were deviating for WX. (We were heading 245 degrees at the time.) he said we needed his approval for that, and we told him that last controller gave us approval to deviate. Current controller called the previous controller on the landline, and was told that we were given a 230 degree heading, not a 'clearance to deviation for WX' (which was technically correct). The current controller barked at us and no further incident resulted. In the future I will be certain to ask for and receive a 'clearance to deviate as necessary for WX' and be sure to advise new controllers of our assigned heading on initial call-up.

Original NASA ASRS Text

Title: FLC DEVIATED FOR WX WHEN ONLY GIVEN HDG FOR DEV.

Narrative: WE WERE ASSIGNED DIRECT DSM VOR BY CTLR. THERE WERE MANY BUILD-UPS IN AREA, AND WE REQUESTED A 230 DEG HDG AND UP TO 12000 FT TO AVOID WX. CTLR GAVE US THE 230 DEG HDG AND WE READ IT BACK. CTLR SAID HE WOULD HAVE HIGHER IN A FEW MINS. CTLR THEN CLRED US TO 12000 FT AND TURNED US OVER TO ZBW (134.7). WE CHKED IN WITH HIM AND DIDN'T TELL HIM OUR HDG FOR WX. THE CTLR CAME ON AND TOLD US THAT GDM WAS 20 DEGS R, AND WE SAID THAT WE WERE DEVIATING FOR WX. (WE WERE HDG 245 DEGS AT THE TIME.) HE SAID WE NEEDED HIS APPROVAL FOR THAT, AND WE TOLD HIM THAT LAST CTLR GAVE US APPROVAL TO DEVIATE. CURRENT CTLR CALLED THE PREVIOUS CTLR ON THE LANDLINE, AND WAS TOLD THAT WE WERE GIVEN A 230 DEG HDG, NOT A 'CLRNC TO DEV FOR WX' (WHICH WAS TECHNICALLY CORRECT). THE CURRENT CTLR BARKED AT US AND NO FURTHER INCIDENT RESULTED. IN THE FUTURE I WILL BE CERTAIN TO ASK FOR AND RECEIVE A 'CLRNC TO DEVIATE AS NECESSARY FOR WX' AND BE SURE TO ADVISE NEW CTLRS OF OUR ASSIGNED HDG ON INITIAL CALL-UP.

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.