Narrative:

We were on a 15 mi final at 3500 ft MSL when final approach told us traffic to follow was at 3.5 mi, an MD88 at 4000 ft MSL. We had visual contact and were cleared visual approach. I did not enjoy the idea the MD88 was 500 ft above us and would descend through our flight path. So, we slowed from 180 KIAS to 160 KIAS allowing more separation for the wake turbulence we would soon encounter. Autoplt was disengaged and we expected at GS intercept some turbulence. The aircraft rolled left 30 degrees, then quickly right 30 degrees. We input our controls to recover. The controller remarked to an aircraft behind us we did not want to obey his speed. (Yet we were cleared visual approach!) I was on a visual approach and had a large aircraft that would descend through my altitude. For safety of flight, I elected to increase following distance to allow the wake turbulence to lessen its intensity. I think controllers should only put same type together if they want to send an aircraft through another one's flight path, especially as you get closer to the ground. When I am on a visual approach, it is now my responsibility to maintain separation. When an aircraft of a larger category is above my altitude and descending. I will slow to allow separation to increase. ATC only had us 3 mi -- I wanted at least 4 mi.

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Original NASA ASRS Text

Title: AN EMB120 FLC EXPERIENCES A TEMPORARY LOSS OF ACFT CTL WHEN ENCOUNTERING WAKE TURB FROM AN MD88 3 PT 5 NM AHEAD N FINAL APCH TO ATL, GA.

Narrative: WE WERE ON A 15 MI FINAL AT 3500 FT MSL WHEN FINAL APCH TOLD US TFC TO FOLLOW WAS AT 3.5 MI, AN MD88 AT 4000 FT MSL. WE HAD VISUAL CONTACT AND WERE CLRED VISUAL APCH. I DID NOT ENJOY THE IDEA THE MD88 WAS 500 FT ABOVE US AND WOULD DSND THROUGH OUR FLT PATH. SO, WE SLOWED FROM 180 KIAS TO 160 KIAS ALLOWING MORE SEPARATION FOR THE WAKE TURB WE WOULD SOON ENCOUNTER. AUTOPLT WAS DISENGAGED AND WE EXPECTED AT GS INTERCEPT SOME TURB. THE ACFT ROLLED L 30 DEGS, THEN QUICKLY R 30 DEGS. WE INPUT OUR CTLS TO RECOVER. THE CTLR REMARKED TO AN ACFT BEHIND US WE DID NOT WANT TO OBEY HIS SPD. (YET WE WERE CLRED VISUAL APCH!) I WAS ON A VISUAL APCH AND HAD A LARGE ACFT THAT WOULD DSND THROUGH MY ALT. FOR SAFETY OF FLT, I ELECTED TO INCREASE FOLLOWING DISTANCE TO ALLOW THE WAKE TURB TO LESSEN ITS INTENSITY. I THINK CTLRS SHOULD ONLY PUT SAME TYPE TOGETHER IF THEY WANT TO SEND AN ACFT THROUGH ANOTHER ONE'S FLT PATH, ESPECIALLY AS YOU GET CLOSER TO THE GND. WHEN I AM ON A VISUAL APCH, IT IS NOW MY RESPONSIBILITY TO MAINTAIN SEPARATION. WHEN AN ACFT OF A LARGER CATEGORY IS ABOVE MY ALT AND DSNDING. I WILL SLOW TO ALLOW SEPARATION TO INCREASE. ATC ONLY HAD US 3 MI -- I WANTED AT LEAST 4 MI.

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.