Deviation from clearance when area of icing and turbulence encountered.

Attributes
ACN	89466
Time
Date	198806
Day	Tue
Local Time Of Day	1801 To 2400
Place
Locale Reference	atc facility : hec
State Reference	CA
Altitude	msl bound lower : 18500 msl bound upper : 20000
Environment
Flight Conditions	IMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zla
Operator	general aviation : corporate
Make Model Name	Small Transport, Low Wing, 2 Recip Eng
Flight Phase	cruise other
Route In Use	enroute airway : zla
Flight Plan	IFR
Person 1
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : private pilot : instrument
Experience	flight time last 90 days : 60 flight time total : 1630 flight time type : 290
ASRS Report	89466
Person 2
Affiliation	government : faa
Function	controller : radar
Qualification	controller : radar
Events
Anomaly	altitude deviation : excursion from assigned altitude inflight encounter : weather non adherence : clearance other spatial deviation
Independent Detector	other controllera
Resolutory Action	none taken : detected after the fact other
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

On a flight (IFR) from slc to lgb at the above location and altitude, we encountered severe turbulence and icing in an embedded storm. My radios were rendered ineffective both navigation and communication and the autoplt wouldn't hold. I transmitted my situation and possible deviation but received no reply. To get out of the cell I turned to a heading of 070 degrees but the altitude loss was approximately 1500'. When the radios became operative the controller was upset because of the deviation. It was a judgement decision, I knew there was clear air at a heading of 070 degrees. I did not know what was straight ahead because nothing was showing on my radar or storm scope and yet I was in this turbulence, icing situation.

Original NASA ASRS Text

Title: DEVIATION FROM CLRNC WHEN AREA OF ICING AND TURBULENCE ENCOUNTERED.

Narrative: ON A FLT (IFR) FROM SLC TO LGB AT THE ABOVE LOCATION AND ALT, WE ENCOUNTERED SEVERE TURB AND ICING IN AN EMBEDDED STORM. MY RADIOS WERE RENDERED INEFFECTIVE BOTH NAV AND COM AND THE AUTOPLT WOULDN'T HOLD. I XMITTED MY SITUATION AND POSSIBLE DEVIATION BUT RECEIVED NO REPLY. TO GET OUT OF THE CELL I TURNED TO A HDG OF 070 DEGS BUT THE ALT LOSS WAS APPROX 1500'. WHEN THE RADIOS BECAME OPERATIVE THE CTLR WAS UPSET BECAUSE OF THE DEVIATION. IT WAS A JUDGEMENT DECISION, I KNEW THERE WAS CLEAR AIR AT A HDG OF 070 DEGS. I DID NOT KNOW WHAT WAS STRAIGHT AHEAD BECAUSE NOTHING WAS SHOWING ON MY RADAR OR STORM SCOPE AND YET I WAS IN THIS TURB, ICING SITUATION.

Data retrieved from NASA's ASRS site as of August 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.