A BEECH 58P AFTER TKOF DECLARED AN EMER DUE TO ALL STATIC PRESSURE SERVED INSTS FAILING CAUSED BY A BROKEN INTERIOR STATIC LINE ALLOWING CABIN PRESSURE TO ENTER AND PRESSURIZE THE STATIC SYS. AFTER DEPRESURIZING THE CABIN THE INSTS RETURNED TO NORMAL.

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AFTER TKOF IN SOLID IMC; AIRSPD INDICATOR FAILED AND WENT TO ZERO. ACFT WOULD NOT CLB ABOVE 900 FT UNTIL 5-6 MINS INTO THE FLT WHEN 500 FPM CLB BEGAN TO 3000 FT (ASSIGNED ALT). IAD CTLR GAVE VECTORS FOR ILS RWY 1R. APCH MISSED WHEN ACFT FAILED TO DSND TO DECISION HT. ACFT DIVERTED TO DAVISON ARMY FIELD FOR RADAR APCHS. THREE MISSED APCHS. PLT THEN DEPRESSURIZED THE ACFT AND STATIC SYS RETURNED TO NORMAL OP. A SUCCESSFUL RADAR APCH WAS MADE TO DAVISON ARMY FIELD (500 FT AND 1 MI). PROB LATER DIAGNOSED AS A BROKEN STATIC LINE INSIDE THE PRESSURE CAPSULE. CABIN PRESSURE TOOK OVER THE AIRSPD; VSI; AND ALTIMETER WHICH ALL GAVE INACCURATE INDICATIONS. THIS WAS A VERY SERIOUS INCIDENT. UNLESS THE ACFT WAS DEPRESSURIZED; THERE WOULD HAVE BEEN NO WAY TO SUCCESSFULLY COMPLETE THE FLT. THERE WAS NO VFR FIELD IN RANGE. PLT TRAINS ANNUALLY AT FLT SCHOOL AND/OR GND SCHOOL. NO BEECHCRAFT PUBS OR TRAINING MATERIALS EVER DESCRIBE THE POSSIBILITY OF SUCH AN EVENT OR HOW TO DETECT IT. THIS SHOULD BE MANDATORY FOR ALL POH AND TRAINING MATERIALS FOR ALL PRESSURIZED ACFT.