FLC OF B727-200 EXPERIENCES WAKE TURB AND RESULTING COMPRESSOR STALL FROM AN MD80 XING THEIR FLT PATH AT FL310.

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THIS RPT IS BEING FILED TO DESCRIBE THE EVENTS LEADING UP TO A COMPRESSOR STALL IN THE #2 ENG OF A B727-222 WHILE IN CRUISE AT FL310. ON THE MORNING OF JAN/XX/98; WE WERE IN CRUISE AT FL310; ENRTE FROM DFW TO SFO. WE WERE BTWN THE NAVAIDS AMA AND FMN WHILE TRACKING ON J58. ACFT CONFIGN WAS STABLE; IE; NO PWR CHANGES; FUEL XFEED CHANGES; OR BLEED CONFIGN WAS TAKING PLACE. ZAB ADVISED US OF XING TFC; R TO L; 10 MI AHEAD; SAME ALT; ON A HDG APPROX 40 DEGS MORE SOUTHERLY THAN OUR OWN. WE VERIFIED THE MENTIONED TFC ON OUR TCASII; AND WERE ABLE TO SEE THE CONTRAILS TRAILING BEHIND THE MENTIONED TFC. WE VISUALLY ACQUIRED THE TFC AS IT PASSED OUR 12 O'CLOCK POS AND THE CONTRAILS STRETCHING ONLY A SHORT DISTANCE BEHIND IT; STILL TO THE R OF OUR FLT PATH. SHORTLY THEREAFTER; WE PASSED THROUGH THE REMAINING WAKE OF THE PRECEDING ACFT (WHICH WE WERE LATER ADVISED WAS AN MD80) AND ENCOUNTERED THE EXPECTED TURB. WE EXPERIENCED MODERATE TURB FOR APPROX 3-5 SECONDS; NOTICED AN EPR DROP ON THE #2 ENG FROM 2.00 DOWN TO 1.50 AND THEN BACK TO 2.00; AND HEARD THE COMPRESSOR STALL 'BANGS.' PAX AND FLT ATTENDANTS CALLED UP SHORTLY AFTER WITH CONCERN REGARDING THE VERY UNEXPECTED TURB AND THE ENG NOISES. ENG INDICATIONS RETURNED TO NORMAL VERY QUICKLY AND THE FLT CONTINUED WITHOUT FURTHER INCIDENT. COMPANY MAINT ADVISED US TO CONTINUE; AND NO FURTHER ACTION WAS REQUIRED BY THE CREW. AREA OF CONCERN: ATC VECTORING OF SAME ALT XING TFC WITH 10 MI OF SEPARATION. LACK OF PLT ABILITY TO SEE AND AVOID WAKE FOLLOWING TURBOJET ACFT; EVEN WHEN TFC IS VISUALLY IDENTED. UNPREDICTABILITY OF WAKE DISSIPATION (IE; DISTANCE IN TRAIL; AND RATE OF DSCNT/DISSIPATION OF WAKE). HAZARDS ASSOCIATED WITH WAKE INDUCED TURB CAUSING ENG COMPRESSOR STALLS DURING HIGH SPD CRUISE AT FLT LEVEL ALTS. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR STATES THAT HE FEELS THE CTLRS NEED TO BE MORE AWARE OF THE POSSIBLE WAKE TURB HANGING AROUND BEHIND AN ACFT AND NOT CLR ANOTHER ACFT AT THE SAME ALT DIRECTLY BEHIND THAT ACFT. A COMPRESSOR STALL AT FL310 IS NOT NORMAL AND NOT SOMETHING ONE CAN PLAN FOR. IT CERTAINLY STARTLED THE PAX AND FLT ATTENDANTS AS WELL AS THE FLC.