WAKE TURB - FLC IS VECTORED AT AN ALT TO INTERCEPT THE GS FROM BELOW WHILE FOLLOWING A HEAVIER ACFT 3 MI AHEAD. THEY TEMPORARILY LOSE CTL OF THEIR ACFT WHEN THEY ENCOUNTER THE WAKE.

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WHILE ON APCH TO HARTSFIELD (ATLANTA) WE WERE GIVEN DSCNT TO 5000 FT. A B-727 WAS IN FRONT OF US AT 6000 FT. HE WAS ON FINAL; WE WERE ON BASE. THE CTLR TOLD US ABOUT HIM. WE RESPONDED THAT WE HAD HIM IN SIGHT. WE WERE CLRED TO FOLLOW HIM VISUALLY. MY COMPANY PROCS DICTATE THAT I USE A LOC AND GS WHEN AVAILABLE. WE WERE BOTH (CAPT AND I) EXPECTING THE WAKE SINCE ATC FOR NO APPARENT REASON LEFT THIS 727 1000 FT ABOVE US. THE AUTOPLT WAS FLYING. AS WE BEGAN DSCNT DOWN THE GS WE ENCOUNTERED THE WAKE. WE FELT A BUMP FOLLOWED BY AN UNCOMMANDED 20 DEG ROLL TO THE R. THE ACFT AUTOPLT WAS DISENGAGED BY THE CAPT AND WE QUICKLY LEFT THE WAKE. THE REST OF THE FLT WAS UNEVENTFUL. THERE WAS NO REASON THE 727 SHOULD NOT HAVE GIVEN A DSCNT. I AM AWARE OF MY ACFT'S RECENT PROBS AND MUST SAY ICE HAD NOTHING WHATSOEVER TO DO WITH IT. THERE WASN'T A CLOUD IN THE SKY. WE WERE TOLD WHAT WE WERE FOLLOWING; BUT WERE NEVER CAUTIONED SPECIFICALLY ABOUT A WAKE. CALLBACK CONVERSATION WITH REPORTER REVEALED THE FOLLOWING: THE RPTR SAID THAT INITIALLY THE CREW LOST CTL OF THE ACFT. THEY WERE ON AUTOPLT AND THE ACFT STARTED ROLLING AND THE AUTOPLT DISCONNECTED. BOTH PLTS GRABBED THE CTL WHEEL; BUT THE ACFT CONTINUED TO ROLL IN SPITE OF FULL OPPOSITE (L) AILERON. THE ROLL STOPPED AT ABOUT 20 DEGS OF R BANK. THE FLC CLBED SLIGHTLY AND ROLLED THE WINGS LEVEL TO RECOVER. AFTERWARDS THE CAPT STAYED 1 DOT HIGH ON THE GS AND THEY HAD NO FURTHER ENCOUNTERS. THE TFC PATTERN DESIGN AT ATL SEEMS TO BE THE PRIMARY FACTOR IN THIS AND A PREVIOUSLY RPTED WAKE ENCOUNTER ACCORDING TO THE RPTR. THE APCH CTLRS PUT ACFT AT SEVERAL DIFFERENT ALTS IN THE PATTERN GOING TO THE SAME RWY. THE ARR SECTOR SEEMS TO BE THE DETERMINATE FOR THE ALT SELECTED. THE RPTR SUGGESTS THAT ONCE TERRAIN CONSIDERATIONS ARE SATISFIED THAT THE CTLRS SHOULD EITHER PUT ALL ACFT AT THE SAME LEVEL OR PUT THE HVY ACFT BELOW THE LIGHTER ACFT WHEN POSSIBLE.