AN SMA PVT PLT MAY HAVE BROKEN AN ASSIGNED ALT AFTER THE PITOT TUBE ICED OVER.

Narrative

UNEVENTFUL FLT FROM PHOENIX; AZ; TO SALT LAKE CITY; UT; UNTIL BEING VECTORED AT APPROX 8000 FT MSL. TEMPORARY LOSS OF ENTIRE PITOT STATIC SYS EVEN PRIOR TO VISIBLE AIRFRAME ICE. WHILE ATTEMPTING TO SWITCH TO ALTERNATE AIR (LOCATED UNDER L HAND SIDE OF INST PANEL); WAS SLOW TO RESPOND TO ATC INSTRUCTIONS AND MAY HAVE BUSTED ALT BASED ON LOSS OF ALTIMETER. AFTER SWITCH TO ALTERNATE STATIC SOURCE; WAS UNABLE TO ACCURATELY JUDGE AIRSPD AND HAD TO USE PWR SETTINGS TO APPROXIMATE APPROPRIATE AIRSPD. THE ICING WAS LIMITED TO A NARROW BAND OF ALT; APPROX 7000- 8500 FT MSL. PLT HAD CONTACTED FSS TWICE PRIOR TO FLT TO CHK ON ICING; THE POSSIBILITY OF WHICH WAS FORECAST; AND SPECIFICALLY ASKED FOR PIREPS OF ICING OF WHICH THERE WERE NONE. PLT ALSO CONTACTED PRESCOTT RADIO ENRTE AND WAS GIVEN NEGATIVE PIREPS REGARDING ICING. NEAR BRYCE CANYON; PLT CONTACTED CEDAR CITY FSS AND WAS GIVEN UPDATED WX FOR SLC INCLUDING AIRMET Z AND SIGMET S. ONCE AGAIN; PLT REQUESTED IF THERE WERE ANY RPTS OF ACTUAL ICING OR FLT DELAYS BASED ON ADVERSE WX (LNDG ILS DELAYS). AGAIN; RESPONSE WAS NEGATIVE. PLT AMENDED FLT PLAN TO HAVE CEDAR CITY AS ALTERNATE BASED ON WX AT CEDAR CITY. POSSIBLE CAUSES OF ALT/ATC INSTRUCTION COMPLIANCE DELAYS: ICING; CAUSING PLT'S ATTN TO BE DIVERTED TO (APPROPRIATELY) AVIATING VERSUS COMMUNICATING. ALTERNATE STATIC SOURCE IS LOCATED DOWN UNDER THE PANEL AND IS DIFFICULT TO JUDGE WHETHER FULLY ON OR NOT BECAUSE IT CAN'T BE VIEWED FROM PLT POS. ALSO; NOT EASY TO TURN ON BECAUSE OF LOCATION. FLT INTO SIGMET/AIRMET FORECAST AND DEPENDENCE ON PIREPS REGARDING ICING. ACR JETS MAY NOT ICE UP WHEN AN SMA WILL.