B-737 IN WAKE TURB FOLLOWING A B-727.

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IN SUM: THE RPTR FLEW A B-737-300 FROM BUR TO PHX. HE FLEW THE KARLO STAR; BUT WAS KEPT HIGH AND FAST BY PHX TRACON. PHX ATCT WAS VECTORING HIM FOR RWY 8R FROM THE N. WHILE IN A 12 DEG LEFT BANK; THE RPTR HIT WAKE TURB BEHIND AN ACR B-727. THIS ROLLED THE ACFT TO THE R ABOUT 12 DEGS; REQUIRING 30 DEGS OF YOKE TRAVEL; AND PITCHED AND YAWED THE ACFT AN UNSTATED AMOUNT. THESE PERTURBATIONS LASTED ABOUT 8 SECONDS. A PAX COMPLAINED TO THE NTSB WHICH IS INVESTIGATING THE INCIDENT. THE RPTR HAS BEEN PROMISED THE OPPORTUNITY TO REVEAL THE FLT DATA RECORDER TAPES OF BOTH ACFT. THERE WERE NO RPTED PAX INJURIES. THE RPTR MADE A PIREP TO THE TWR. BOTH ARTCC AND ATCT TAPES HAVE BEEN PULLED BECAUSE OF THE SIMILARITY TO AN ACFT ACCIDENT. UNDER CURRENT INVESTIGATION. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR HAS DONE ACCIDENT INVESTIGATION WORK FOR HIS ACR AND HIS PLT'S UNION. HE APPEARS TO BE HIGHLY QUALIFIED. THE RPTR HAS HAD VERY LITTLE FURTHER CONTACT WITH THE NTSB SINCE THIS ASRS RPT WAS SUBMITTED. THE NTSB HAS PROMISED HIM THAT HE WILL BE ALLOWED TO READ OUT THE FLT DATA RECORDER TAPES OF BOTH ACFT WHEN THEY BECOME AVAILABLE. HE IS QUITE GRATEFUL THAT HIS ACFT HAD A 30 CHANNEL FDR. THE RPTR IS CERTAIN THAT HE WAS FOLLOWING A 727 BUT HE DOES NOT KNOW ITS CONFIGN. THE RPTR'S ACFT WAS CLEAN. AUTOTHROTTLE AND AUTOPLT OFF; WITH THE FO FLYING THE ACFT WAS RELATIVELY HVY FOR LNDG. THE RPTR HAS WITNESSES IN THE ACFT WILLING TO TESTIFY THAT THE PERSON THAT COMPLAINED TO THE NTSB WAS MISTAKEN OR EXAGGERATING ABOUT SCREAMING AND THE ANGLE OF BANK. THE RPTR COMPLAINED ABOUT THE 'MICRO MGMNT' BY THE ATCT LCL CTLR OF HDG; ALT AND AIRSPD LEAVING THE PLT NO WAY TO AVOID THE PRECEDING ACFT. PHX TWR HAS CHANGED ITS PROCS SO THAT ALL ACFT COMING FROM THE SAME DIRECTION WILL LAND ON THE SAME RWY; EVEN WHEN THE OTHER RWY IS UNDERUTILIZED. THIS CAN CAUSE UNNECESSARY WAKE TURB ENCOUNTERS. SUPPLEMENTAL INFO FROM ACN 286785: SHORTLY THEREAFTER WE ENCOUNTERED THE 727'S WAKE TURB. THE ACFT BANKED L APPROX 15 DEGS AND THEN TO THE R APPROX 20 DEGS. I ESTIMATE THAT WE WERE AT ABOUT 15-20 DEGS OFF PERPENDICULAR TO HIS FLT PATH WHEN THIS OCCURRED. IT LASTED FOR ABOUT 5 SECONDS. AFTER EXITING THE WAKE; THE CAPT MADE A COMMENT TO ATC AND THEN A PA TO THE PAX TO REASSURE THEM THAT THERE WAS NO PROB. THE ENCOUNTER ACTUALLY SURPRISED US IN THE SEVERITY (LIGHT TO MODERATE TURB) AND THE FACT THAT WE HIT IT AT ALL. I DID NOT THINK THAT OUR FLT PATHS WOULD CROSS.