Lear 55 experiences a wake turbulence encounter on ILS approach behind a B757.

Attributes
ACN	281499
Time
Date	199408
Day	Thu
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : atl
State Reference	GA
Altitude	msl bound lower : 3800 msl bound upper : 3800
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : atl
Operator	general aviation : corporate
Make Model Name	Learjet 55
Operating Under FAR Part	other : unknown
Navigation In Use	Other
Flight Phase	descent : approach
Route In Use	approach : straight in enroute : on vectors
Flight Plan	IFR
Aircraft 2
Operator	common carrier : air carrier
Make Model Name	B757 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Navigation In Use	Other Other
Flight Phase	descent : approach
Route In Use	approach : straight in enroute : on vectors
Flight Plan	IFR
Person 1
Affiliation	Other
Function	flight crew : captain oversight : pic
Qualification	pilot : atp pilot : cfi
Experience	flight time last 90 days : 80 flight time total : 3500 flight time type : 1800
ASRS Report	281499
Person 2
Affiliation	Other
Function	flight crew : first officer
Qualification	pilot : instrument pilot : commercial
Events
Anomaly	inflight encounter other other anomaly other anomaly other
Independent Detector	other flight crewa
Resolutory Action	flight crew : exited adverse environment flight crew : regained aircraft control
Consequence	faa : reviewed incident with flight crew
Supplementary
Primary Problem	Aircraft
Air Traffic Incident	other

Narrative:

Approximately 3 mi outside the marker at atl runway 8L approach descending to the published altitude we encountered wake turbulence which caused an uncontrollable roll to the right of 30 degrees of bank. When ATC was questioned, we were told that we were 5 mi in-trail of a boeing 757. I flew the rest of the approach at a much steeper angle than the GS and had no further problems. Possibly increasing separation criteria even greater may be an answer, but ATC should inform aircraft which are following a 757 or a heavy even if you meet the minimum separation.

Original NASA ASRS Text

Title: LEAR 55 EXPERIENCES A WAKE TURB ENCOUNTER ON ILS APCH BEHIND A B757.

Narrative: APPROX 3 MI OUTSIDE THE MARKER AT ATL RWY 8L APCH DSNDING TO THE PUBLISHED ALT WE ENCOUNTERED WAKE TURB WHICH CAUSED AN UNCTLABLE ROLL TO THE R OF 30 DEGS OF BANK. WHEN ATC WAS QUESTIONED, WE WERE TOLD THAT WE WERE 5 MI IN-TRAIL OF A BOEING 757. I FLEW THE REST OF THE APCH AT A MUCH STEEPER ANGLE THAN THE GS AND HAD NO FURTHER PROBS. POSSIBLY INCREASING SEPARATION CRITERIA EVEN GREATER MAY BE AN ANSWER, BUT ATC SHOULD INFORM ACFT WHICH ARE FOLLOWING A 757 OR A HVY EVEN IF YOU MEET THE MINIMUM SEPARATION.

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.