Light transport experiences wake turbulence when 4 mi behind large transport on approach.

Attributes
ACN	227217
Time
Date	199211
Day	Mon
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : atl
State Reference	GA
Altitude	msl bound lower : 3500 msl bound upper : 3500
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : atl
Operator	common carrier : air carrier
Make Model Name	Light Transport, Low Wing, 2 Turboprop Eng
Navigation In Use	Other Other
Flight Phase	descent : approach
Route In Use	approach : visual
Flight Plan	IFR
Aircraft 2
Operator	common carrier : air carrier
Make Model Name	Large Transport, Low Wing, 2 Turbojet Eng
Navigation In Use	Other Other
Flight Phase	descent : approach
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : cfi pilot : atp
Experience	flight time last 90 days : 280 flight time total : 13000 flight time type : 4000
ASRS Report	227217
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp
Events
Anomaly	inflight encounter other other anomaly other
Independent Detector	other flight crewa
Resolutory Action	none taken : anomaly accepted
Consequence	Other
Supplementary
Primary Problem	Aircraft
Air Traffic Incident	other

Narrative:

Upon turning onto the localizer for the visual approach to atl's runway 27L, approach control advised that we were 4 mi behind our traffic, an large transport Y. We then hit 6 strong jolts of wake turbulence, after which our ride returned to smooth. No one was hurt. Wake turbulence is a problem. It is so common in the atl arrival area that we tend to ignore it, accepting it as a regular part of flying. I hit it on an average of once every 10 approachs to atl, or once every 2 to 3 'flight days.' usually, behind an medium large transport or large transport Y, it is 3 medium jolts in which nothing in the aircraft is disturbed. But, behind an large transport Y, wake turbulence is always strong -- much stronger than other 'non heavy' aircraft. Recommendation: assign 'heavy' aircraft separation standards for large transport Y aircraft.

Original NASA ASRS Text

Title: LTT EXPERIENCES WAKE TURB WHEN 4 MI BEHIND LGT ON APCH.

Narrative: UPON TURNING ONTO THE LOC FOR THE VISUAL APCH TO ATL'S RWY 27L, APCH CTL ADVISED THAT WE WERE 4 MI BEHIND OUR TFC, AN LGT Y. WE THEN HIT 6 STRONG JOLTS OF WAKE TURB, AFTER WHICH OUR RIDE RETURNED TO SMOOTH. NO ONE WAS HURT. WAKE TURB IS A PROBLEM. IT IS SO COMMON IN THE ATL ARR AREA THAT WE TEND TO IGNORE IT, ACCEPTING IT AS A REGULAR PART OF FLYING. I HIT IT ON AN AVERAGE OF ONCE EVERY 10 APCHS TO ATL, OR ONCE EVERY 2 TO 3 'FLT DAYS.' USUALLY, BEHIND AN MLG OR LGT Y, IT IS 3 MEDIUM JOLTS IN WHICH NOTHING IN THE ACFT IS DISTURBED. BUT, BEHIND AN LGT Y, WAKE TURB IS ALWAYS STRONG -- MUCH STRONGER THAN OTHER 'NON HVY' ACFT. RECOMMENDATION: ASSIGN 'HVY' ACFT SEPARATION STANDARDS FOR LGT Y ACFT.

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.