Narrative:

As I joined up with V21 I could see some cumulus ahead and I asked coast control about any reported tops. He responded by stating that he was not even aware of any significant clouds in the area. He suggested that I ask the next sector controller. By the time of my handoff, approximately 20 mi north of sna, I was at 5000', in and out of some very light cumulus. The indicated temperature on my side-mounted thermometer was -2 degrees C. That controller was too busy to converse about tops. I was then handed off to the next ontario sector, where I was cleared to 9000'. At this time I was about 10 mi north of pdz along V21. That controller asked about icing at my altitude (I was now solid IMC). I informed him that I was experiencing very light rime icing. I was told that another aircraft at 10000' ahead was also experiencing light rime. I had put on the pitot heat immediately on my first entry into the clouds and had tried the carburetor heat several times as a precaution. As I reached 10500' my climb rate diminished significantly (100 FPM or less), and the rate of ice build up increased. I now could see about .35' of ice on the thermometer and wing leading edges. The engine started to sound rough, and I immediately applied full carburetor heat. An updraft got us up to 11000', but I had ice now at around 1/2' on the thermometer leading edge. Ice was visible on the wing leading edge, but not on the surfaces of the wings. I could see no way to climb out of the predicament, and got no encouragement about breaking out soon. I asked for an immediate descent just as my airspeed indicator started to drop rapidly. I instinctively put the plane nose down, and added full throttle, having visions of stall/spin. The airspeed rapidly bled off, and within 2 seconds went to 0. I realized that the pitot tube was frozen and pulled the power back to cruise. I was told to turn to a heading of 210 degrees during my descent and was given a holding clearance. I immediately took out my approach plates to find an alternate landing spot. I copied the holding clearance in about 2 mins. The ice I could see was not dissipating. However, in about 5 mins I regained my airspeed indication. I then headed toward pdz to hold as instructed. At 6000' I broke out below the clouds. I told the controller that I wanted to get some indication of the WX through the banning pass, and asked to switch to flight watch. I received permission, but was unable to get any response from hawthorne flight watch. I was told that I could not continue IFR at that altitude. I informed him that I would go VFR toward banning at 5500. As I progressed, the cloud bases continued to go lower, and I informed the controller that I could not maintain VFR at that altitude. I asked for a descent to 3500'. He approved the descent. However, he was having difficulty receiving my transponder (mode C). At about 5 mi east of pdz I was handed off to the next sector controller. That controller responded to my, 'small aircraft with you descending out of 4000,' with, 'what and where are you, and what do you want?' I attempted to inform her that I was handed off. She told me that, 'you were given a frequency change, not a handoff.' I informed her that I was not given a change in transponder code, but was told to switch to her frequency. On telling her of my position, she told me that I was about to enter the march AFB arsa. I asked for a frequency to contact, but got no response. She finally responded with a request for my position, whereupon she said, 'apparently you just went through the march arsa.' I told her that I believed too busy to check my exact position. I was definitely overloaded with work. During the flight I clearly flew into predicated icing, although neither I nor the controllers were aware of its severity. Later I may have inadvertently penetrated an area west/O the proper clearance. What was evident to me was my own lack of planned alternatives prior to the flight. I assumed that since the flight would be conducted under IFR control in VFR conditions that I did not plan to have escape routes.

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Original NASA ASRS Text

Title: GA SMA ENCOUNTERS ICING AND HAS TO DIVERT. ON DIVERSION UNAUTH PENETRATION OF ARSA DUE TO POOR ATC COORD.

Narrative: AS I JOINED UP WITH V21 I COULD SEE SOME CUMULUS AHEAD AND I ASKED COAST CTL ABOUT ANY RPTED TOPS. HE RESPONDED BY STATING THAT HE WAS NOT EVEN AWARE OF ANY SIGNIFICANT CLOUDS IN THE AREA. HE SUGGESTED THAT I ASK THE NEXT SECTOR CTLR. BY THE TIME OF MY HDOF, APPROX 20 MI N OF SNA, I WAS AT 5000', IN AND OUT OF SOME VERY LIGHT CUMULUS. THE INDICATED TEMP ON MY SIDE-MOUNTED THERMOMETER WAS -2 DEGS C. THAT CTLR WAS TOO BUSY TO CONVERSE ABOUT TOPS. I WAS THEN HANDED OFF TO THE NEXT ONTARIO SECTOR, WHERE I WAS CLRED TO 9000'. AT THIS TIME I WAS ABOUT 10 MI N OF PDZ ALONG V21. THAT CTLR ASKED ABOUT ICING AT MY ALT (I WAS NOW SOLID IMC). I INFORMED HIM THAT I WAS EXPERIENCING VERY LIGHT RIME ICING. I WAS TOLD THAT ANOTHER ACFT AT 10000' AHEAD WAS ALSO EXPERIENCING LIGHT RIME. I HAD PUT ON THE PITOT HEAT IMMEDIATELY ON MY FIRST ENTRY INTO THE CLOUDS AND HAD TRIED THE CARB HEAT SEVERAL TIMES AS A PRECAUTION. AS I REACHED 10500' MY CLB RATE DIMINISHED SIGNIFICANTLY (100 FPM OR LESS), AND THE RATE OF ICE BUILD UP INCREASED. I NOW COULD SEE ABOUT .35' OF ICE ON THE THERMOMETER AND WING LEADING EDGES. THE ENG STARTED TO SOUND ROUGH, AND I IMMEDIATELY APPLIED FULL CARB HEAT. AN UPDRAFT GOT US UP TO 11000', BUT I HAD ICE NOW AT AROUND 1/2' ON THE THERMOMETER LEADING EDGE. ICE WAS VISIBLE ON THE WING LEADING EDGE, BUT NOT ON THE SURFACES OF THE WINGS. I COULD SEE NO WAY TO CLIMB OUT OF THE PREDICAMENT, AND GOT NO ENCOURAGEMENT ABOUT BREAKING OUT SOON. I ASKED FOR AN IMMEDIATE DSCNT JUST AS MY AIRSPD INDICATOR STARTED TO DROP RAPIDLY. I INSTINCTIVELY PUT THE PLANE NOSE DOWN, AND ADDED FULL THROTTLE, HAVING VISIONS OF STALL/SPIN. THE AIRSPD RAPIDLY BLED OFF, AND WITHIN 2 SECS WENT TO 0. I REALIZED THAT THE PITOT TUBE WAS FROZEN AND PULLED THE PWR BACK TO CRUISE. I WAS TOLD TO TURN TO A HDG OF 210 DEGS DURING MY DSCNT AND WAS GIVEN A HOLDING CLRNC. I IMMEDIATELY TOOK OUT MY APCH PLATES TO FIND AN ALTERNATE LNDG SPOT. I COPIED THE HOLDING CLRNC IN ABOUT 2 MINS. THE ICE I COULD SEE WAS NOT DISSIPATING. HOWEVER, IN ABOUT 5 MINS I REGAINED MY AIRSPD INDICATION. I THEN HEADED TOWARD PDZ TO HOLD AS INSTRUCTED. AT 6000' I BROKE OUT BELOW THE CLOUDS. I TOLD THE CTLR THAT I WANTED TO GET SOME INDICATION OF THE WX THROUGH THE BANNING PASS, AND ASKED TO SWITCH TO FLT WATCH. I RECEIVED PERMISSION, BUT WAS UNABLE TO GET ANY RESPONSE FROM HAWTHORNE FLT WATCH. I WAS TOLD THAT I COULD NOT CONTINUE IFR AT THAT ALT. I INFORMED HIM THAT I WOULD GO VFR TOWARD BANNING AT 5500. AS I PROGRESSED, THE CLOUD BASES CONTINUED TO GO LOWER, AND I INFORMED THE CTLR THAT I COULD NOT MAINTAIN VFR AT THAT ALT. I ASKED FOR A DSCNT TO 3500'. HE APPROVED THE DSCNT. HOWEVER, HE WAS HAVING DIFFICULTY RECEIVING MY XPONDER (MODE C). AT ABOUT 5 MI E OF PDZ I WAS HANDED OFF TO THE NEXT SECTOR CTLR. THAT CTLR RESPONDED TO MY, 'SMA WITH YOU DSNDING OUT OF 4000,' WITH, 'WHAT AND WHERE ARE YOU, AND WHAT DO YOU WANT?' I ATTEMPTED TO INFORM HER THAT I WAS HANDED OFF. SHE TOLD ME THAT, 'YOU WERE GIVEN A FREQ CHANGE, NOT A HDOF.' I INFORMED HER THAT I WAS NOT GIVEN A CHANGE IN XPONDER CODE, BUT WAS TOLD TO SWITCH TO HER FREQ. ON TELLING HER OF MY POS, SHE TOLD ME THAT I WAS ABOUT TO ENTER THE MARCH AFB ARSA. I ASKED FOR A FREQ TO CONTACT, BUT GOT NO RESPONSE. SHE FINALLY RESPONDED WITH A REQUEST FOR MY POS, WHEREUPON SHE SAID, 'APPARENTLY YOU JUST WENT THROUGH THE MARCH ARSA.' I TOLD HER THAT I BELIEVED TOO BUSY TO CHK MY EXACT POS. I WAS DEFINITELY OVERLOADED WITH WORK. DURING THE FLT I CLEARLY FLEW INTO PREDICATED ICING, ALTHOUGH NEITHER I NOR THE CTLRS WERE AWARE OF ITS SEVERITY. LATER I MAY HAVE INADVERTENTLY PENETRATED AN AREA W/O THE PROPER CLRNC. WHAT WAS EVIDENT TO ME WAS MY OWN LACK OF PLANNED ALTERNATIVES PRIOR TO THE FLT. I ASSUMED THAT SINCE THE FLT WOULD BE CONDUCTED UNDER IFR CTL IN VFR CONDITIONS THAT I DID NOT PLAN TO HAVE ESCAPE ROUTES.

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.