Heading track deviation in a non adherence to ATC clearance.

Attributes
ACN	309584
Time
Date	199507
Day	Sun
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : atl
State Reference	GA
Altitude	msl bound lower : 14000 msl bound upper : 14000
Environment
Flight Conditions	Mixed
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : ztl
Operator	common carrier : air carrier
Make Model Name	Fokker 100
Operating Under FAR Part	Part 121
Navigation In Use	Other Other
Flight Phase	cruise other
Route In Use	enroute : on vectors
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
ASRS Report	309584
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp
Events
Anomaly	inflight encounter : weather non adherence : clearance other anomaly other other spatial deviation
Independent Detector	aircraft equipment other aircraft equipment : unspecified other flight crewa
Resolutory Action	controller : issued new clearance flight crew : exited adverse environment flight crew : returned to intended course or assigned course flight crew : declared emergency
Consequence	faa : reviewed incident with flight crew
Supplementary
Primary Problem	Weather
Air Traffic Incident	Pilot Deviation

Narrative:

Deviation from clearance. Departed atlanta with heavy thunderstorm activity in vicinity. Level at 14000 ft, assigned a 150 degree heading. Emerged from IFR condition to find large cell directly on nose at about 4 mi. Painted green on radar but saw lightning in cell. Could not talk to ZTL due to frequency congestion and turned to a heading of 175 degrees. Checked on TCASII and verified there was no conflicting traffic. Finally able to talk to center and informed them of new heading. Center was quite displeased we turned without his permission. 175 degree heading was then assigned and we were told to change frequency.

Original NASA ASRS Text

Title: HDG TRACK DEV IN A NON ADHERENCE TO ATC CLRNC.

Narrative: DEV FROM CLRNC. DEPARTED ATLANTA WITH HVY TSTM ACTIVITY IN VICINITY. LEVEL AT 14000 FT, ASSIGNED A 150 DEG HDG. EMERGED FROM IFR CONDITION TO FIND LARGE CELL DIRECTLY ON NOSE AT ABOUT 4 MI. PAINTED GREEN ON RADAR BUT SAW LIGHTNING IN CELL. COULD NOT TALK TO ZTL DUE TO FREQ CONGESTION AND TURNED TO A HDG OF 175 DEGS. CHKED ON TCASII AND VERIFIED THERE WAS NO CONFLICTING TFC. FINALLY ABLE TO TALK TO CTR AND INFORMED THEM OF NEW HDG. CTR WAS QUITE DISPLEASED WE TURNED WITHOUT HIS PERMISSION. 175 DEG HDG WAS THEN ASSIGNED AND WE WERE TOLD TO CHANGE FREQ.

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.