Narrative:

Flight bhm-mco flight plan calls for crossing cty at 17000 ft, ocf at or below 11000 ft with a descent to 9000 ft for orl approach using the leese 9 arrival (ocf 129 degree radial -- orl 309 degree radial). After leese, we were advised of traffic (an L1011) at our 10 O'clock, 5 mi, at 11000 ft. We had seen this traffic on TCASII and, at this time, acquired the aircraft visually and called the traffic. We were advised to maintain visual separation as the L1011 was going to be descended through our altitude. At this point no problem existed, although we both commented that ATC would probably put the L1011 directly in front of us. The L1011 was descended to 9000 ft. It was apparently on the alma transition of the leese 9 arrival. As the L1011 was about to cross in front of us, it was given a 090 degree heading and we were given a 090 degree heading (we were then told 'caution wake turbulence') which put us directly in trail of the L1011. Wind was from 060 degrees. We were dead behind the L1011 because all we could see was a circle with wings. If we had been higher we might have escaped but we couldn't climb, couldn't turn left because either of those would put us into his wake. Could not descend because we would be in the same situation. Could not turn right because of departure traffic. As we talked about the situation, I felt a bump, then the aircraft rolled violently to the right and pitched down disconnecting the autoplt. The captain recovered control of the aircraft. I then tried to call our flight attendant but received no answer. As I was about to get up to check, a non revenue crew member answered the phone and told me the flight attendant had been injured. We then requested priority handling with an immediate landing. This flight attendant is now on workman's compensation with head, neck and knee injuries. Return to work is pending. This occurred because ATC insists on merging large aircraft from atl on L9 with smaller aircraft on L9 from over ocf, and putting these aircraft in trail with the larger aircraft in front. They descend the smaller aircraft to below 10000 ft where the airspeed limit is 250 KTS where the larger aircraft is kept above 10000 ft where they can do anything they want. The controllers don't seem to really understand the result of this action. They apparently believe their duty is discharged when they say 'caution wake turbulence.' the object is to have a nice, orderly parade of aircraft in a straight line so their job is easier, not really concerned that they put aircraft at risk. We were lucky, if we had been closer (either to the L1011 or the airport) we might have lost control of the aircraft. These controllers run minimum separation and sooner or later they are going to cause an aircraft to hit the ground. Callback conversation with reporter revealed the following information: reporter and his captain had talked about ATC putting the L1011 in front of them and the hazard associated with that. He says that, in the future, he would request a heading and/or altitude change to counter the danger of wake turbulence because traffic being funneled into the airport and apparently in a relatively narrow corridor, ATC tends to bring the larger jets in at altitudes above 10000 ft and keep their speed up while the commuter turboprops are descended below 10000 ft where the speed is limited to 250 KTS. Reporter makes valid observation that, since the turboprops can maintain 250 KTS, that should be an adequate speed for all aircraft on the arrival and all aircraft should be kept in trail instead of descending a widebody transport in front of the smaller aircraft. In this case the upset was extreme and the flight attendant sustained serious injuries.

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Original NASA ASRS Text

Title: EMB120 ACFT IN TRAIL WITH L1011 ENCOUNTERED SEVERE WAKE TURB RESULTING IN INJURY TO FLT ATTENDANT.

Narrative: FLT BHM-MCO FLT PLAN CALLS FOR XING CTY AT 17000 FT, OCF AT OR BELOW 11000 FT WITH A DSCNT TO 9000 FT FOR ORL APCH USING THE LEESE 9 ARR (OCF 129 DEG RADIAL -- ORL 309 DEG RADIAL). AFTER LEESE, WE WERE ADVISED OF TFC (AN L1011) AT OUR 10 O'CLOCK, 5 MI, AT 11000 FT. WE HAD SEEN THIS TFC ON TCASII AND, AT THIS TIME, ACQUIRED THE ACFT VISUALLY AND CALLED THE TFC. WE WERE ADVISED TO MAINTAIN VISUAL SEPARATION AS THE L1011 WAS GOING TO BE DSNDED THROUGH OUR ALT. AT THIS POINT NO PROB EXISTED, ALTHOUGH WE BOTH COMMENTED THAT ATC WOULD PROBABLY PUT THE L1011 DIRECTLY IN FRONT OF US. THE L1011 WAS DSNDED TO 9000 FT. IT WAS APPARENTLY ON THE ALMA TRANSITION OF THE LEESE 9 ARR. AS THE L1011 WAS ABOUT TO CROSS IN FRONT OF US, IT WAS GIVEN A 090 DEG HDG AND WE WERE GIVEN A 090 DEG HDG (WE WERE THEN TOLD 'CAUTION WAKE TURB') WHICH PUT US DIRECTLY IN TRAIL OF THE L1011. WIND WAS FROM 060 DEGS. WE WERE DEAD BEHIND THE L1011 BECAUSE ALL WE COULD SEE WAS A CIRCLE WITH WINGS. IF WE HAD BEEN HIGHER WE MIGHT HAVE ESCAPED BUT WE COULDN'T CLB, COULDN'T TURN L BECAUSE EITHER OF THOSE WOULD PUT US INTO HIS WAKE. COULD NOT DSND BECAUSE WE WOULD BE IN THE SAME SIT. COULD NOT TURN R BECAUSE OF DEP TFC. AS WE TALKED ABOUT THE SIT, I FELT A BUMP, THEN THE ACFT ROLLED VIOLENTLY TO THE R AND PITCHED DOWN DISCONNECTING THE AUTOPLT. THE CAPT RECOVERED CTL OF THE ACFT. I THEN TRIED TO CALL OUR FLT ATTENDANT BUT RECEIVED NO ANSWER. AS I WAS ABOUT TO GET UP TO CHK, A NON REVENUE CREW MEMBER ANSWERED THE PHONE AND TOLD ME THE FLT ATTENDANT HAD BEEN INJURED. WE THEN REQUESTED PRIORITY HANDLING WITH AN IMMEDIATE LNDG. THIS FLT ATTENDANT IS NOW ON WORKMAN'S COMPENSATION WITH HEAD, NECK AND KNEE INJURIES. RETURN TO WORK IS PENDING. THIS OCCURRED BECAUSE ATC INSISTS ON MERGING LARGE ACFT FROM ATL ON L9 WITH SMALLER ACFT ON L9 FROM OVER OCF, AND PUTTING THESE ACFT IN TRAIL WITH THE LARGER ACFT IN FRONT. THEY DSND THE SMALLER ACFT TO BELOW 10000 FT WHERE THE AIRSPD LIMIT IS 250 KTS WHERE THE LARGER ACFT IS KEPT ABOVE 10000 FT WHERE THEY CAN DO ANYTHING THEY WANT. THE CTLRS DON'T SEEM TO REALLY UNDERSTAND THE RESULT OF THIS ACTION. THEY APPARENTLY BELIEVE THEIR DUTY IS DISCHARGED WHEN THEY SAY 'CAUTION WAKE TURB.' THE OBJECT IS TO HAVE A NICE, ORDERLY PARADE OF ACFT IN A STRAIGHT LINE SO THEIR JOB IS EASIER, NOT REALLY CONCERNED THAT THEY PUT ACFT AT RISK. WE WERE LUCKY, IF WE HAD BEEN CLOSER (EITHER TO THE L1011 OR THE ARPT) WE MIGHT HAVE LOST CTL OF THE ACFT. THESE CTLRS RUN MINIMUM SEPARATION AND SOONER OR LATER THEY ARE GOING TO CAUSE AN ACFT TO HIT THE GND. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR AND HIS CAPT HAD TALKED ABOUT ATC PUTTING THE L1011 IN FRONT OF THEM AND THE HAZARD ASSOCIATED WITH THAT. HE SAYS THAT, IN THE FUTURE, HE WOULD REQUEST A HDG AND/OR ALT CHANGE TO COUNTER THE DANGER OF WAKE TURB BECAUSE TFC BEING FUNNELED INTO THE ARPT AND APPARENTLY IN A RELATIVELY NARROW CORRIDOR, ATC TENDS TO BRING THE LARGER JETS IN AT ALTS ABOVE 10000 FT AND KEEP THEIR SPD UP WHILE THE COMMUTER TURBOPROPS ARE DSNDED BELOW 10000 FT WHERE THE SPD IS LIMITED TO 250 KTS. RPTR MAKES VALID OBSERVATION THAT, SINCE THE TURBOPROPS CAN MAINTAIN 250 KTS, THAT SHOULD BE AN ADEQUATE SPD FOR ALL ACFT ON THE ARR AND ALL ACFT SHOULD BE KEPT IN TRAIL INSTEAD OF DSNDING A WDB IN FRONT OF THE SMALLER ACFT. IN THIS CASE THE UPSET WAS EXTREME AND THE FLT ATTENDANT SUSTAINED SERIOUS INJURIES.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.