WAKE TURB ENCOUNTER AT LOW ALT.

Narrative

ON APCH BEHIND B-757 BY 4 MI; THIS ACFT TOUCHED DOWN AN AIRBUS CLRED INTO POS WHEN WE WERE 2 MI OUT CLRED FOR TKOF WE WERE 1.5 MI OUT 20 FT FROM TOUCHDOWN IN B757. ACFT ENCOUNTERED VIOLENT WAKE TURB. RAPID ROLL TO R MAX PWR FULL L AILERON. ACFT STILL MADE FIRM TOUCHDOWN ON RWY. SEPARATION STILL TOO CLOSE IF ACFT HAD ABORTED OR WE HAD GONE AROUND IT WOULD HAVE REQUIRED SOME RAPID MOVEMENTS AS IT WAS THE TURB WE ENCOUNTERED WAS TOO MUCH FOR ACFT TO RECOVER FROM. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR HAD 2 ACFT IN FRONT OF HIM DURING HIS APCH. 1 ACFT WAS LNDG 4 MI AHEAD (A B-757) AND THE ACFT IN TKOF POS WAS AN A-300. HIS APCH HAD BEEN SMOOTH UNTIL THE FLARE FOR LNDG OCCURRED AND ACFT DROPPED 20 FT. BECAUSE THIS WAS LOW LEVEL TURB; THE CAPT FELT STRONGLY IT CAME FROM THE TKOF ACFT. THE SUDDEN DROP DURING FLARE CAUSED A FIRM LNDG. THE CAPT WAS UPSET ENOUGH THAT HE WENT TO TWR SUPVR TO TELL HIM THE LNDG AND TKOF SEPARATIONS WERE TOO SHORT. TWR SUPVR INDICATED THERE WAS NOTHING IMPROPER WITH THE DISTANCES BTWN HIS ACFT AND THE OTHER ACFT. CAPT EXPRESSED GREAT DISAPPOINTMENT THAT THE TWR SUPVR COULDN'T CHANGE ANYTHING. CAPT WAS SIMPLY VERY UPSET OVER THE SUDDEN LOSS OF LIFT RESULTING IN A FIRM LNDG FOR HIS ACFT. CAPT FEELS ATC SHOULD ISSUE GREATER SEPARATION.