A FALCON 50 FO RPTED THAT HE AND THE CAPT EXCEEDED 200 KTS BELOW CLE'S CLASS B AIRSPACE.

Narrative

WE WERE BEING VECTORED FOR THE ILS RWY 24 TO CGF ARPT. IT WAS A CLR; BUT DARK NIGHT; SO WE ELECTED TO FLY THE ILS INSTEAD OF TAKING A VISUAL APCH. WE WERE LEVEL AT 4000 FT AT 250 KTS. THE CTLR GAVE US A VECTOR FOR OUR BASE LEG AND TOLD US TO MAINTAIN 3000 FT AND TO FLY '190 KTS OR LESS.' THE CAPT BEGAN TO DSND TO 3000 FT WHILE SLOWING TO 190 KTS. THE APCH AND LNDG WERE UNEVENTFUL. AFTER LNDG I LOOKED AT THE LOW ALT CHART; AGAIN; AND DISCOVERED THAT BELOW 4000 FT; WE WERE UNDER THE FLOOR OF THE CLEVELAND CLASS B AIRSPACE. WE SHOULD HAVE BEEN AT 200 KTS OR LESS BEFORE DSNDING TO 3000 FT. I DON'T KNOW IF THE CTLR'S SPD INSTRUCTIONS WERE FOR SEPARATION PURPOSES OR IF HE RECOGNIZED THAT WE WERE WELL ABOVE THE MAX SPD FOR OPERATING UNDER THE FLOOR OF THE CLASS B. THE CTLR NEVER SAID ANOTHER WORD ABOUT OUR SPD AND NEVER ASKED US WHAT WE WERE INDICATING AS WE LEFT 4000 FT FOR 3000 FT. WE ARE USUALLY CAREFUL AND WATCH FOR THIS; BUT WERE CAUGHT OFF GUARD BEING AT A NEW ARPT AND AT NIGHT. IN THE FUTURE; WE WILL BE 'HEADS UP' TO THIS.