A DA-90 FLT CREW ENCOUNTERS THE WAKE TURB FROM A B777 8 NM AHEAD ON RWY 28R AT SFO; CA.

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WAKE TURB ENCOUNTER; FALCON 900 VERSUS BOEING 777 (BOEING ONE - FALCON NOTHING). BOTH ACFT WERE FLYING CHARTED VISUAL APCHS TO SFO RWY 28R. THE B777 WAS CLRED THE FMS VISUAL; THE FALCON 900 WAS FLYING THE QUIET BRIDGE VISUAL COUPLED LNAV/VNAV ON AUTOPLT AS A CUSTOM WAYPOINT; STORED FLT PLAN. NORCAL APCH ISSUED AN ADVISORY THAT THE 'B777 WAS 8.5 MI AHEAD FOR RWY 28R; CAUTION WAKE TURB.' UPON RECEIVING THE ATIS RPT THAT CHARTED VISUAL APCHS FOR RWYS 28 WERE IN USE; I APPENDED A CUSTOM FLT PLAN ONTO THE EXISTING ACTIVE FLT PLAN FOLLOWING THE MODESTO ARR. THIS FLT PLAN IS STORED BECAUSE OF OUR FREQ USE OF THIS PROC. IT CONTAINS ALL THE FIXES AND ALTS OF THE QUIET BRIDGE VISUAL. WE WERE CLRED FOR THE APCH AND RECEIVED A CAUTION FOR THE B777 8.5 MI AHEAD ALSO LNDG RWY 28R AND INSTRUCTED TO REDUCE SPD TO 180 KTS. WE CONFIGURED TO SLATS PLUS FLAPS 7 DEGS AND SLOWED TO 180 KTS. INERTIAL WINDS DISPLAYED ON THE EHSI INDICATED 14 KTS HEADWIND OR ABOUT 280 DEGS AT 14 KTS. AT APPROX 8 MI FROM TOUCHDOWN (THE B777 HAVING ALREADY LANDED) WE ENCOUNTERED VICIOUS WAKE TURB/WINGTIP VORTICES THAT FELT LIKE IMPACTING A WALL. THE ACFT BEGAN A HARD R ROLL ACCOMPANIED BY THE STALL WARNING AND ANGLE OF ATTACK INDEXER DISPLAYING RED (INDEXER SET FOR 1.3 VERSUS GREEN). I IMMEDIATELY OVERRODE THE AUTOPLT AND AGGRESSIVELY APPLIED FULL L AILERON AND FULL L RUDDER INPUTS. THE ACFT CONTINUED TO ROLL TO APPROX 35 DEGS R AGAINST FULL OPPOSITE CTL BEFORE CTL WAS ESTABLISHED. THE STALL WARNING SOUNDED THROUGHOUT THIS ACTION AND THE NOSE WAS LOWERED APPROX 8 DEGS BELOW THE HORIZON. SIMULTANEOUSLY; THE OTHER PLT ADVANCED THE THROTTLES. RECOVERY WAS COMPLETED WITH AN ESTIMATED LOSS OF NO MORE THAN 200 FT; PROBABLY LESS; SPD AT RECOVERY WAS 220 KTS. THE APCH WAS CONTINUED TO A LNDG WELL ABOVE THE GS. AFTERMATH: THIS WAS A POSITIONING FLT WITH NO PAX ABOARD. ALL OF THE LOOSE EQUIP; MANUALS; PENCILS; ETC; IN THE COCKPIT AREA WERE ON THE FLOOR. LOOSE MAGAZINES; SEAT CUSHIONS; PILLOWS; AND VARIOUS OTHER ITEMS WERE STREWN ABOUT THE CABIN. BLUE WATER SPILLED FROM THE LAVATORY. CABINETS IN THE LAVATORY OPENED AND SPILLED THEIR CONTENTS. WHILE THE TOILET LID WAS OPEN UNDER THE NEGATIVE 'G;' A CAN OF AIR FRESHENER ACTUALLY MADE ITS WAY INTO THE BOWL. I RECOVERED 45 CENTS WORTH OF LOOSE CHANGE DISLODGED FROM THE CABIN SEATS. QUESTIONS: THE B777 WAS CLRED FOR THE FMS VISUAL. WHILE IT IS IMPOSSIBLE TO KNOW; IT IS LIKELY THAT ACFT WAS FOLLOWING IT PRECISELY. THAT BRINGS THE QUESTION: IS THE ANGLE OF THAT APCH STEEPER THAN THAT OF THE QUIET BRIDGE VISUAL? WITH OVER 8 MI SEPARATION AND 14 KTS OF HEADWIND; IT WOULD SEEM THAT THE WINGTIP VORTICES WOULD HAVE BEEN SAFELY UNDER US. SHOULD THE SEPARATION BEHIND THE HVY B777 AND SMALLER JETS BE INCREASED? IF THE FMS VISUAL IS SIGNIFICANTLY DIFFERENT; IT SHOULD BE A PUBLIC USE APCH.