WAKE ENCOUNTER -- ACR B737-200 HITS THE WAKE OF A B747- 300 AND IS UPSET. THE B737-200 RECOVERS AND MAKES A GAR.

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WE WERE ON BASE LEG AT 4000 FT; SPD 210 KTS ASSIGNED; HDG 300 DEGS ASSIGNED; WE WERE ADVISED THAT WE WERE FOLLOWING A FOREIGN ACR B747-300 AND TO CALL HIM INSIGHT. WE CALLED HIM INSIGHT AND WERE GIVEN A 330 DEG HDG TO INTERCEPT AND TOLD TO FOLLOW HIM. NO SPACING INFO WAS GIVEN US BY ATC. AFTER ESTABLISHING ON THE 330 DEG HDG; WE SAW THE B747 WAS LESS THAN 5 MI AHEAD ON OUR TCASII. WE STARTED SLOWING RAPIDLY AND ATC TOLD US TO HOLD 170 KTS TILL 5 DME. OUR SPACING CONTINUED TO REDUCE DESPITE CONTINUING TO SLOW. WE WERE TOLD TO CONTACT TWR AND; AFTER CHKING IN; WERE TOLD WE HAD MINIMUM SPACING BEHIND THE B747. IMMEDIATELY THEREAFTER; WE HIT HIS WAKE. OUR ACFT ROLLED R AND NOSED DOWN. THE ACFT REACHED APPROX 50 DEGS R BANK AND 5-10 DEGS NOSE DOWN DURING RECOVERY. ALT WAS APPROX 2700 FT MSL AT RECOVERY; A NORMAL MISSED APCH WAS INITIATED AND AN UNEVENTFUL VFR LNDG MADE. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THIS RPTR WAS FLYING A B737-200 AND WAS BEING SEQUENCED BEHIND A B747-300. THE APCH CTLR KEPT ASKING IF THE CAPT SAW THE ARPT AND THE PRECEDING ACFT. THE CTLR SAID THAT THE B747 WAS 5 MI AHEAD AND WAS DOING 170 KTS. THE CAPT SAID THAT AT THIS TIME HE WAS DOING ABOUT 210 KTS; AS REQUESTED; AND WAS ON A SQUARE BASE LEG. JUST AFTER THE FLC OF THE B737 CALLED THE B747 INSIGHT; THE APCH CTLR TURNED THEM ON A DOGLEG TO FINAL CLOSING THE IN-TRAIL DISTANCE. THEY WERE THEN TURNED OVER TO THE TWR CTLR. THE TWR CTLR RPTED THAT THEY WERE AT MINIMUM SEPARATION. THE B737 CREW HAD BEGUN TO SLOW AND WITH THE TWR'S ADVISORY THEY SLOWED EVEN FURTHER. THE TCASII SHOWED THAT THEY WERE ONLY 2 1/2 - 3 MI BEHIND THE B747 AND THEY WERE AT 150 KTS. THE B747 HAD BEEN TOLD TO MAINTAIN AT LEAST 170 KTS TO THE OM; HOWEVER ITS SPD WAS MUCH SLOWER. AT ABOUT 10 DME AND 3300 FT THE B737 HIT THE B747'S WAKE. THE B737'S PITCH CHANGED FROM ABOUT 4-5 DEGS NOSE UP TO 5-10 DEGS NOSE DOWN AND THE ACFT ROLLED R TO ABOUT 50 DEGS OF BANK. THE CAPT ATTEMPTED TO CORRECT THE R BANK WITH L AILERON; BUT THE ACFT DID NOT RESPOND. HE FINALLY TOOK OUT THE FULL L AILERON DEFLECTION AND; AS HE WAS DOING SO; HE PUT IN FULL L RUDDER TO ROLL THE WINGS LEVEL. HE THEN PULLED BACK ON THE ELEVATOR WHILE APPLYING SOME PWR TO BRING THE NOSE UP. THE TOTAL ALT LOSS WAS 600 FT. THE CAPT WAS A HIGHLY EXPERIENCED AEROBATIC PLT WHO HAD BEEN TRAINED IN THE MIL. THE FO HAD NOT HAD AEROBATIC TRAINING. ACCORDING TO THE CAPT THE FO SAID THAT WHEN THE ACFT WOULD NOT ROLL WINGS LEVEL INITIALLY HE THOUGHT THAT HE WAS DEAD. THE UPSET AND THE RECOVERY LASTED ABOUT 30 SECONDS.