Reporter encounters wake turbulence from boeing 757.

Attributes
ACN	311365
Time
Date	199506
Day	Thu
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : dvv airport : den
State Reference	CO
Altitude	msl bound lower : 14000 msl bound upper : 14000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zdv
Operator	common carrier : air carrier
Make Model Name	Brasilia EMB-120 All Series
Operating Under FAR Part	Part 121
Flight Phase	descent other
Route In Use	arrival other enroute airway : zdv
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 other
Route In Use	arrival other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 250 flight time total : 8500 flight time type : 200
ASRS Report	311365
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : instrument pilot : commercial
Events
Anomaly	altitude deviation : excursion from assigned altitude inflight encounter other other anomaly other
Independent Detector	other flight crewa
Resolutory Action	flight crew : exited adverse environment flight crew : returned to intended course or assigned course flight crew : took evasive action
Consequence	Other
Supplementary
Air Traffic Incident	other

Narrative:

We were descending on the arrival when I noticed traffic in a descending right turn in front of us joining the same arrival. When center didn't mention traffic for us I called and asked if there was traffic at 12 O'clock for us. Center advised traffic ahead B757 4 1/2 mi. Traffic disappeared below a cloud layer for 2-3 mins. Within 5 mins after spotting traffic we hit his wake. He had disappeared below the cloud layer and we were still 500-800 ft above cloud layer. Our aircraft was rolled into a 35-45 degree bank. Captain recovered by disconnecting autoplt, full right rudder, and adding full power. PNF then called ATC to advise climbing due to wake turbulence encounter. I believe there is an ongoing study about the B757 and whether it should be classified as a heavy category aircraft. My feeling is that it should. This is my third encounter with a B757 wake in the last 3 yrs. The first 2 times were closer to the landing airport (2-5 mi) and aircraft was rolled past 45 degree of bank. Suggestions: 1) why couldn't there be parallel arrs, one for heavy or large aircraft and one for smaller. Denver has parallel STAR's and why couldn't they use them that way, 2) controllers could be more aware of the aircraft and the vectors given. I have often had a DC10 run over the top of me 1000-2000 ft above or vector behind a heavy and had to ask for a stagger to trail a larger aircraft. Callback conversation with reporter revealed the following information: the reporter stated he was flying an EMB120/rt. This reporter has had 2 other encounters and all were B757 generated wake. The 2 past experiences were on short final. This encounter at altitude was as alarming as the past 2 encounters on short final due to the abruptness. The practice of overflying heavy's and then descending the heavy through the altitude just in front of the commuter when the commuter pilot responds he has the heavy in sight has been a repeated complaint.

Original NASA ASRS Text

Title: RPTR ENCOUNTERS WAKE TURB FROM BOEING 757.

Narrative: WE WERE DSNDING ON THE ARR WHEN I NOTICED TFC IN A DSNDING R TURN IN FRONT OF US JOINING THE SAME ARR. WHEN CTR DIDN'T MENTION TFC FOR US I CALLED AND ASKED IF THERE WAS TFC AT 12 O'CLOCK FOR US. CTR ADVISED TFC AHEAD B757 4 1/2 MI. TFC DISAPPEARED BELOW A CLOUD LAYER FOR 2-3 MINS. WITHIN 5 MINS AFTER SPOTTING TFC WE HIT HIS WAKE. HE HAD DISAPPEARED BELOW THE CLOUD LAYER AND WE WERE STILL 500-800 FT ABOVE CLOUD LAYER. OUR ACFT WAS ROLLED INTO A 35-45 DEG BANK. CAPT RECOVERED BY DISCONNECTING AUTOPLT, FULL R RUDDER, AND ADDING FULL PWR. PNF THEN CALLED ATC TO ADVISE CLBING DUE TO WAKE TURB ENCOUNTER. I BELIEVE THERE IS AN ONGOING STUDY ABOUT THE B757 AND WHETHER IT SHOULD BE CLASSIFIED AS A HVY CATEGORY ACFT. MY FEELING IS THAT IT SHOULD. THIS IS MY THIRD ENCOUNTER WITH A B757 WAKE IN THE LAST 3 YRS. THE FIRST 2 TIMES WERE CLOSER TO THE LNDG ARPT (2-5 MI) AND ACFT WAS ROLLED PAST 45 DEG OF BANK. SUGGESTIONS: 1) WHY COULDN'T THERE BE PARALLEL ARRS, ONE FOR HVY OR LARGE ACFT AND ONE FOR SMALLER. DENVER HAS PARALLEL STAR'S AND WHY COULDN'T THEY USE THEM THAT WAY, 2) CTLRS COULD BE MORE AWARE OF THE ACFT AND THE VECTORS GIVEN. I HAVE OFTEN HAD A DC10 RUN OVER THE TOP OF ME 1000-2000 FT ABOVE OR VECTOR BEHIND A HVY AND HAD TO ASK FOR A STAGGER TO TRAIL A LARGER ACFT. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATED HE WAS FLYING AN EMB120/RT. THIS RPTR HAS HAD 2 OTHER ENCOUNTERS AND ALL WERE B757 GENERATED WAKE. THE 2 PAST EXPERIENCES WERE ON SHORT FINAL. THIS ENCOUNTER AT ALT WAS AS ALARMING AS THE PAST 2 ENCOUNTERS ON SHORT FINAL DUE TO THE ABRUPTNESS. THE PRACTICE OF OVERFLYING HVY'S AND THEN DSNDING THE HVY THROUGH THE ALT JUST IN FRONT OF THE COMMUTER WHEN THE COMMUTER PLT RESPONDS HE HAS THE HVY IN SIGHT HAS BEEN A REPEATED COMPLAINT.

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.