Narrative:

We departed san carlos (sql) at XX00 pm and climbed to 15500 ft on a direct VFR route to hood river via red bluff VOR (to avoid whitmore MOA) with flight following. After passing red bluff VOR we climbed to 15500 ft to take advantage of favorable winds forecast to the north and to get above the smoke that seemed to be rising ahead where the terrain around shasta rises. Visibility deteriorated to the point that we could barely see the ground. It was clear that we would soon be IFR if we were not already. We were with ZOA so I called in and asked for IFR clearance direct to hood river which was granted at 16000 ft. Shortly after clearance was granted we transitioned from smoke to clouds and started to pick up a thin layer of clear ice. This continued for about 8 mi with very little buildup and then we hit freezing rain and snow. At the same time the storm scope started to show a line of discharges dead ahead for 10-20 mi where it had previously been absolutely clear. With ice collecting at a noticeable rate and thunderstorms ahead I reported icing and asked for a 60 degree right turn to take us to the east around the thunderstorms and towards what was normally drier air. Within mins we were getting strong up and down drafts that made it difficult to maintain altitude and it became clear to me that we could not afford to continue to pick up ice and stay in the air. I reported to the controller that we were reversing course back to red bluff because of ice and he asked if we wanted an altitude change as well. We were given clearance to climb to 18000 ft and applied full power but could not climb at 120 mph which I felt was a minimum speed to avoid a stall with 1/2 to 3/4 of an inch of ice. The rear engine started to overheat (possible low speed nose up full power attitude did not push enough air through the rear scoop and ice may have shut down some of the opening). We were also getting uncommanded altitude excursions of up to 1000 ft. I was loaded up with tasks trying to keep the plane upright, keep the rear engine alive and hold a heading that would take us clear of the storm. At one point I glanced at the engine instruments and came back to the center of my scan to find the plane in a 50 degree right hand bank descending at 2000 FPM -- turbulence or my error I don't know -- this was the only moment that really scared me. The controller called and asked why we were not at the assigned altitude. I responded that we were unable to climb and would like a descent. He reminded me that we were still IFR and needed to comply with altitude assignments and then cleared us for a descent to 13000 ft. We soon were clear of the clouds and started to shed the ice at about 14000 ft. A return to our original course at an altitude of 11000 ft put us through some rain and smooth air and out the other side in hazy smoke. A number of thoughts: 1) I should immediately have taken action to avoid the ice when it first appeared -- with an outside air temperature of about -2 degrees C a request for 2000 ft lower would have probably done the trick. We are taught to climb and that was my immediate request, but if I had thought about it I had enough data to come up with a better solution. Perhaps the controller could have passed on information on forecasted or reported freezing levels. I was also unprepared for IFR conditions and had not done my normal IFR preflight planning. Satellite photos, duats and past experience suggested it would be IFR all the way. Had I been prepared I would probably have asked for lower. The lesson here is always prepare for the worst, plan your options before you launch. 2) my decision to change course 60 degrees was calculated to get us around the storm but still keep some vector in the direction we wanted to go, this is stupid. I failed to confess to myself that our flight plan could no longer be executed. I am a rational person and always thought that I would not get caught in the ego trap, but I didn't turn around because I hate to take no for an answer. This is a valuable lesson and I have no idea how to teach it as I have read about it a dozen times yet I still went out and tried to bull my way through. 3) I should have told the controller that I was unable to maintain altitude but I was so loaded up with tasks aviating and navigating that communicating was low on the priority list. The clause that allows pilots to take the action they feel is required to get out of a jamb without severe penalties is very important to maintain -- it allowed me to take the action I needed to without first getting permission. Next time I will simply key the microphone and report I can't hold altitude as I am sorting out the flying.

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Original NASA ASRS Text

Title: A CESSNA SKYMASTER PLT FLEW INTO ICING CONDITIONS AND WAS UNABLE TO MAINTAIN ASSIGNED ALT NEAR RBL.

Narrative: WE DEPARTED SAN CARLOS (SQL) AT XX00 PM AND CLBED TO 15500 FT ON A DIRECT VFR RTE TO HOOD RIVER VIA RED BLUFF VOR (TO AVOID WHITMORE MOA) WITH FLT FOLLOWING. AFTER PASSING RED BLUFF VOR WE CLBED TO 15500 FT TO TAKE ADVANTAGE OF FAVORABLE WINDS FORECAST TO THE N AND TO GET ABOVE THE SMOKE THAT SEEMED TO BE RISING AHEAD WHERE THE TERRAIN AROUND SHASTA RISES. VISIBILITY DETERIORATED TO THE POINT THAT WE COULD BARELY SEE THE GND. IT WAS CLR THAT WE WOULD SOON BE IFR IF WE WERE NOT ALREADY. WE WERE WITH ZOA SO I CALLED IN AND ASKED FOR IFR CLRNC DIRECT TO HOOD RIVER WHICH WAS GRANTED AT 16000 FT. SHORTLY AFTER CLRNC WAS GRANTED WE TRANSITIONED FROM SMOKE TO CLOUDS AND STARTED TO PICK UP A THIN LAYER OF CLR ICE. THIS CONTINUED FOR ABOUT 8 MI WITH VERY LITTLE BUILDUP AND THEN WE HIT FREEZING RAIN AND SNOW. AT THE SAME TIME THE STORM SCOPE STARTED TO SHOW A LINE OF DISCHARGES DEAD AHEAD FOR 10-20 MI WHERE IT HAD PREVIOUSLY BEEN ABSOLUTELY CLR. WITH ICE COLLECTING AT A NOTICEABLE RATE AND TSTMS AHEAD I RPTED ICING AND ASKED FOR A 60 DEG R TURN TO TAKE US TO THE E AROUND THE TSTMS AND TOWARDS WHAT WAS NORMALLY DRIER AIR. WITHIN MINS WE WERE GETTING STRONG UP AND DOWN DRAFTS THAT MADE IT DIFFICULT TO MAINTAIN ALT AND IT BECAME CLR TO ME THAT WE COULD NOT AFFORD TO CONTINUE TO PICK UP ICE AND STAY IN THE AIR. I RPTED TO THE CTLR THAT WE WERE REVERSING COURSE BACK TO RED BLUFF BECAUSE OF ICE AND HE ASKED IF WE WANTED AN ALT CHANGE AS WELL. WE WERE GIVEN CLRNC TO CLB TO 18000 FT AND APPLIED FULL PWR BUT COULD NOT CLB AT 120 MPH WHICH I FELT WAS A MINIMUM SPD TO AVOID A STALL WITH 1/2 TO 3/4 OF AN INCH OF ICE. THE REAR ENG STARTED TO OVERHEAT (POSSIBLE LOW SPD NOSE UP FULL PWR ATTITUDE DID NOT PUSH ENOUGH AIR THROUGH THE REAR SCOOP AND ICE MAY HAVE SHUT DOWN SOME OF THE OPENING). WE WERE ALSO GETTING UNCOMMANDED ALT EXCURSIONS OF UP TO 1000 FT. I WAS LOADED UP WITH TASKS TRYING TO KEEP THE PLANE UPRIGHT, KEEP THE REAR ENG ALIVE AND HOLD A HEADING THAT WOULD TAKE US CLR OF THE STORM. AT ONE POINT I GLANCED AT THE ENG INSTS AND CAME BACK TO THE CTR OF MY SCAN TO FIND THE PLANE IN A 50 DEG R HAND BANK DSNDING AT 2000 FPM -- TURB OR MY ERROR I DON'T KNOW -- THIS WAS THE ONLY MOMENT THAT REALLY SCARED ME. THE CTLR CALLED AND ASKED WHY WE WERE NOT AT THE ASSIGNED ALT. I RESPONDED THAT WE WERE UNABLE TO CLB AND WOULD LIKE A DSCNT. HE REMINDED ME THAT WE WERE STILL IFR AND NEEDED TO COMPLY WITH ALT ASSIGNMENTS AND THEN CLRED US FOR A DSCNT TO 13000 FT. WE SOON WERE CLR OF THE CLOUDS AND STARTED TO SHED THE ICE AT ABOUT 14000 FT. A RETURN TO OUR ORIGINAL COURSE AT AN ALT OF 11000 FT PUT US THROUGH SOME RAIN AND SMOOTH AIR AND OUT THE OTHER SIDE IN HAZY SMOKE. A NUMBER OF THOUGHTS: 1) I SHOULD IMMEDIATELY HAVE TAKEN ACTION TO AVOID THE ICE WHEN IT FIRST APPEARED -- WITH AN OUTSIDE AIR TEMP OF ABOUT -2 DEGS C A REQUEST FOR 2000 FT LOWER WOULD HAVE PROBABLY DONE THE TRICK. WE ARE TAUGHT TO CLB AND THAT WAS MY IMMEDIATE REQUEST, BUT IF I HAD THOUGHT ABOUT IT I HAD ENOUGH DATA TO COME UP WITH A BETTER SOLUTION. PERHAPS THE CTLR COULD HAVE PASSED ON INFO ON FORECASTED OR RPTED FREEZING LEVELS. I WAS ALSO UNPREPARED FOR IFR CONDITIONS AND HAD NOT DONE MY NORMAL IFR PREFLT PLANNING. SATELLITE PHOTOS, DUATS AND PAST EXPERIENCE SUGGESTED IT WOULD BE IFR ALL THE WAY. HAD I BEEN PREPARED I WOULD PROBABLY HAVE ASKED FOR LOWER. THE LESSON HERE IS ALWAYS PREPARE FOR THE WORST, PLAN YOUR OPTIONS BEFORE YOU LAUNCH. 2) MY DECISION TO CHANGE COURSE 60 DEGS WAS CALCULATED TO GET US AROUND THE STORM BUT STILL KEEP SOME VECTOR IN THE DIRECTION WE WANTED TO GO, THIS IS STUPID. I FAILED TO CONFESS TO MYSELF THAT OUR FLT PLAN COULD NO LONGER BE EXECUTED. I AM A RATIONAL PERSON AND ALWAYS THOUGHT THAT I WOULD NOT GET CAUGHT IN THE EGO TRAP, BUT I DIDN'T TURN AROUND BECAUSE I HATE TO TAKE NO FOR AN ANSWER. THIS IS A VALUABLE LESSON AND I HAVE NO IDEA HOW TO TEACH IT AS I HAVE READ ABOUT IT A DOZEN TIMES YET I STILL WENT OUT AND TRIED TO BULL MY WAY THROUGH. 3) I SHOULD HAVE TOLD THE CTLR THAT I WAS UNABLE TO MAINTAIN ALT BUT I WAS SO LOADED UP WITH TASKS AVIATING AND NAVING THAT COMMUNICATING WAS LOW ON THE PRIORITY LIST. THE CLAUSE THAT ALLOWS PLTS TO TAKE THE ACTION THEY FEEL IS REQUIRED TO GET OUT OF A JAMB WITHOUT SEVERE PENALTIES IS VERY IMPORTANT TO MAINTAIN -- IT ALLOWED ME TO TAKE THE ACTION I NEEDED TO WITHOUT FIRST GETTING PERMISSION. NEXT TIME I WILL SIMPLY KEY THE MIKE AND RPT I CAN'T HOLD ALT AS I AM SORTING OUT THE FLYING.

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.