Narrative:

Operating on radar vector 250 degree heading from baton intersection on the dfw buj 7 arrival, level 5000 ft, 240 KIAS, clean, autoplt on, encountered severe wake turbulence involving 25-30 degree bank to right followed by 15-20 degree bank left, lasting 3-5 seconds. When encountered, autoplt was disconnected and wings were manually attempted to be leveled. After we obtained somewhat aircraft control still in the wake turbulence, started an immediate climb to approximately 125 ft above 5000 ft, exited the wake turbulence and flight landed without further incident. We notified approach and asked what aircraft we were following. They replied an MD80, 12 O'clock, 4 mi. We did show this aircraft on TCASII at that position. Dfw continually takes jets over the top of turboprop aircraft at 6000 ft. Standard arrs have turboprop aircraft cross buj, bpr, aqn, scy vors at 6000 ft and jets at 10000 ft setting up wake turbulence problems closer to the airport. With wake turbulence being at the height of safety issues today, no one (ATC or FAA) seems to care about problems with the arrs at dfw. I guess not until someone crashes! 'Rules by death' if you refuse separation, then you are given a penalty vector and go to the end of the line just to be put in the same position later! This is an obvious safety problem that must be addressed, especially for times like this, high tech new efficient wings of jets slow clean and heavy (20 NM) from airport on calm clear mornings! This is an issue that needs to be addressed at dfw immediately before something happens! Ideas that may help this problem! 1) make controllers more aware of en route transition to approach regarding wake turbulence. The most dangerous times for wake turbulence is clean slow and heavy, ie, when transitioning to the landing phase. Jets are slowed in a clean confign. And on landing, jets have full flaps and gear! Not the time to give you the warning. It's too late. 2) make dfw arrival procedures where everyone crosses buj, bpr, scy, aqn at same altitude and 230-250 KIAS eliminating the wake turbulence problem later. 3) when approach control radar vectors you, they need to let you know who you are following or what aircraft is in front of you. 4) make all separations between jets and turboprops 5 mi not to be below and trailing jets. 5) an immediate study of wake turbulence regarding intensity of new modern high efficiency wings. 6) we are just lucky the aircraft we were following was not a B757 or heavy! Callback conversation with reporter revealed the following information: reporter participated in the wake turbulence callback study. Reporter was distressed over the fact that ATC procedures as handled by TRACON always set up the turboprop aircraft to have a wake turbulence encounter. This is done by always having the turbojets descend through the turboprop altitude. This assures that the lower flying turboprop will always encounter wake from the preceding turbojet. Along with that situation, there are no wake turbulence warnings. Reporter's flight crew were both startled and distressed over the sudden rolling of the aircraft. They felt fortunate that they had a cruise speed of 250 KTS which allowed them to regain control of aircraft in 3-4 seconds. Reporter commented on the fact that this situation occurs far more than what is reported as many flcs are not aware of the ASRS reporting program.

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Original NASA ASRS Text

Title: WAKE TURB ENCOUNTER DURING LOW ALT CRUISE FLT ON VECTORS ON FINAL APCH.

Narrative: OPERATING ON RADAR VECTOR 250 DEG HDG FROM BATON INTXN ON THE DFW BUJ 7 ARR, LEVEL 5000 FT, 240 KIAS, CLEAN, AUTOPLT ON, ENCOUNTERED SEVERE WAKE TURB INVOLVING 25-30 DEG BANK TO R FOLLOWED BY 15-20 DEG BANK L, LASTING 3-5 SECONDS. WHEN ENCOUNTERED, AUTOPLT WAS DISCONNECTED AND WINGS WERE MANUALLY ATTEMPTED TO BE LEVELED. AFTER WE OBTAINED SOMEWHAT ACFT CTL STILL IN THE WAKE TURB, STARTED AN IMMEDIATE CLB TO APPROX 125 FT ABOVE 5000 FT, EXITED THE WAKE TURB AND FLT LANDED WITHOUT FURTHER INCIDENT. WE NOTIFIED APCH AND ASKED WHAT ACFT WE WERE FOLLOWING. THEY REPLIED AN MD80, 12 O'CLOCK, 4 MI. WE DID SHOW THIS ACFT ON TCASII AT THAT POS. DFW CONTINUALLY TAKES JETS OVER THE TOP OF TURBOPROP ACFT AT 6000 FT. STANDARD ARRS HAVE TURBOPROP ACFT CROSS BUJ, BPR, AQN, SCY VORS AT 6000 FT AND JETS AT 10000 FT SETTING UP WAKE TURB PROBS CLOSER TO THE ARPT. WITH WAKE TURB BEING AT THE HEIGHT OF SAFETY ISSUES TODAY, NO ONE (ATC OR FAA) SEEMS TO CARE ABOUT PROBS WITH THE ARRS AT DFW. I GUESS NOT UNTIL SOMEONE CRASHES! 'RULES BY DEATH' IF YOU REFUSE SEPARATION, THEN YOU ARE GIVEN A PENALTY VECTOR AND GO TO THE END OF THE LINE JUST TO BE PUT IN THE SAME POS LATER! THIS IS AN OBVIOUS SAFETY PROB THAT MUST BE ADDRESSED, ESPECIALLY FOR TIMES LIKE THIS, HIGH TECH NEW EFFICIENT WINGS OF JETS SLOW CLEAN AND HVY (20 NM) FROM ARPT ON CALM CLR MORNINGS! THIS IS AN ISSUE THAT NEEDS TO BE ADDRESSED AT DFW IMMEDIATELY BEFORE SOMETHING HAPPENS! IDEAS THAT MAY HELP THIS PROB! 1) MAKE CTLRS MORE AWARE OF ENRTE TRANSITION TO APCH REGARDING WAKE TURB. THE MOST DANGEROUS TIMES FOR WAKE TURB IS CLEAN SLOW AND HVY, IE, WHEN TRANSITIONING TO THE LNDG PHASE. JETS ARE SLOWED IN A CLEAN CONFIGN. AND ON LNDG, JETS HAVE FULL FLAPS AND GEAR! NOT THE TIME TO GIVE YOU THE WARNING. IT'S TOO LATE. 2) MAKE DFW ARR PROCS WHERE EVERYONE CROSSES BUJ, BPR, SCY, AQN AT SAME ALT AND 230-250 KIAS ELIMINATING THE WAKE TURB PROB LATER. 3) WHEN APCH CTL RADAR VECTORS YOU, THEY NEED TO LET YOU KNOW WHO YOU ARE FOLLOWING OR WHAT ACFT IS IN FRONT OF YOU. 4) MAKE ALL SEPARATIONS BTWN JETS AND TURBOPROPS 5 MI NOT TO BE BELOW AND TRAILING JETS. 5) AN IMMEDIATE STUDY OF WAKE TURB REGARDING INTENSITY OF NEW MODERN HIGH EFFICIENCY WINGS. 6) WE ARE JUST LUCKY THE ACFT WE WERE FOLLOWING WAS NOT A B757 OR HVY! CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR PARTICIPATED IN THE WAKE TURB CALLBACK STUDY. RPTR WAS DISTRESSED OVER THE FACT THAT ATC PROCS AS HANDLED BY TRACON ALWAYS SET UP THE TURBOPROP ACFT TO HAVE A WAKE TURB ENCOUNTER. THIS IS DONE BY ALWAYS HAVING THE TURBOJETS DSND THROUGH THE TURBOPROP ALT. THIS ASSURES THAT THE LOWER FLYING TURBOPROP WILL ALWAYS ENCOUNTER WAKE FROM THE PRECEDING TURBOJET. ALONG WITH THAT SITUATION, THERE ARE NO WAKE TURB WARNINGS. RPTR'S FLC WERE BOTH STARTLED AND DISTRESSED OVER THE SUDDEN ROLLING OF THE ACFT. THEY FELT FORTUNATE THAT THEY HAD A CRUISE SPD OF 250 KTS WHICH ALLOWED THEM TO REGAIN CTL OF ACFT IN 3-4 SECONDS. RPTR COMMENTED ON THE FACT THAT THIS SITUATION OCCURS FAR MORE THAN WHAT IS RPTED AS MANY FLCS ARE NOT AWARE OF THE ASRS RPTING PROGRAM.

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.