An emb-145 flight crew turns off assigned course for WX avoidance.

Attributes
ACN	518020
Time
Date	200107
Day	Wed
Place
Locale Reference	airport : pit.airport
State Reference	PA
Altitude	msl single value : 10000
Environment
Flight Conditions	IMC
Light	Daylight
Aircraft 1
Controlling Facilities	tower : oak.tower
Operator	common carrier : air carrier
Make Model Name	EMB ERJ 145 ER&LR
Flight Phase	descent : intermediate altitude descent : approach
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp
Experience	flight time last 90 days : 270 flight time total : 3900 flight time type : 270
ASRS Report	518020
Events
Anomaly	inflight encounter : weather non adherence : clearance other anomaly other other spatial deviation
Resolutory Action	controller : issued new clearance flight crew : took precautionary avoidance action flight crew : exited adverse environment
Supplementary
Problem Areas	Environmental Factor Flight Crew Human Performance Weather ATC Human Performance
Primary Problem	Weather

Narrative:

The heading assigned to us was going to put us into a cell on radar. Approach controller was busy. Finally advised him that we needed 090 degrees or 180 degree heading instead of 140 degree heading for the WX. By the time he gave us 180 degree heading, we were too close to turn right to 180 degrees without going through the cell we wanted to avoid. I advised controller that we needed 090 degree heading. Nothing we could have done, but controller was not very happy due to heavy traffic in that area. Captain is turning without keeping me in the loop made it more complicated than it should be in my opinion, and that CRM principle was undermined at that time.

Original NASA ASRS Text

Title: AN EMB-145 FLT CREW TURNS OFF ASSIGNED COURSE FOR WX AVOIDANCE.

Narrative: THE HDG ASSIGNED TO US WAS GOING TO PUT US INTO A CELL ON RADAR. APCH CTLR WAS BUSY. FINALLY ADVISED HIM THAT WE NEEDED 090 DEGS OR 180 DEG HDG INSTEAD OF 140 DEG HDG FOR THE WX. BY THE TIME HE GAVE US 180 DEG HDG, WE WERE TOO CLOSE TO TURN R TO 180 DEGS WITHOUT GOING THROUGH THE CELL WE WANTED TO AVOID. I ADVISED CTLR THAT WE NEEDED 090 DEG HDG. NOTHING WE COULD HAVE DONE, BUT CTLR WAS NOT VERY HAPPY DUE TO HVY TFC IN THAT AREA. CAPT IS TURNING WITHOUT KEEPING ME IN THE LOOP MADE IT MORE COMPLICATED THAN IT SHOULD BE IN MY OPINION, AND THAT CRM PRINCIPLE WAS UNDERMINED AT THAT TIME.

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.