THE PURPOSE OF THE FLT WAS TO SURVEY THE AREA & PHOTOGRAPH PROPERTY DAMAGE CAUSED BY HURRICANE HUGO. WHILE IN THE AREA, THE WX BEGAN TO DETERIORATE & THE PLT ELECTED TO LAND AT EAST COOPER ARPT. HE RPRTD THAT WHILE LANDING WITH A TAILWIND, THE ACFT FLOATED OVER HALFWAY DOWN THE RWY BEFORE TOUCHING DOWN. HE WAS UNABLE TO STOP ON THE REMAINING (WET) RWY. AFTER DEPARTING THE RWY, THE ACFT ENCOUNTERED MUDDY TERRAIN & NOSED OVER. THE PLT RPRTD HE DID NOT SEE THE WINDSOCK DUE TO ITS LOCATION & SHREDDED/DIRTY CONDITION (FROM HURRICANE DAMAGE). ALSO, HE NOTED THAT UNICOM WAS NOT AVAILABLE DUE TO THE LACK OF ELECTRICAL POWER AT THE ARPT. THE PLT ESTD THE WX WAS: 1500' OVC, VIS 3 MI WITH LIGHT RAIN & FOG, WIND 15 TO 20 KTS. APRX 13 MI WEST AT CHARLESTON, SC, THE 1550 EDT WX WAS IN PART: 2300' OVC, VIS 7 MI, WIND FROM 050 DEG AT 12 KTS.