Air carrier on approach to las questioned ATC's application of wake turbulence separation procedures...

Attributes
ACN	779298
Time
Date	200803
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : las.airport
State Reference	NV
Altitude	msl single value : 7000
Aircraft 1
Controlling Facilities	tracon : l30.tracon
Operator	common carrier : air carrier
Make Model Name	A320
Operating Under FAR Part	Part 121
Flight Phase	descent : approach
Route In Use	approach : visual
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Experience	flight time last 90 days : 150 flight time total : 22500 flight time type : 1300
ASRS Report	779298
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Events
Anomaly	inflight encounter : wake turbulence non adherence : published procedure other anomaly
Independent Detector	other flight crewa
Resolutory Action	none taken : anomaly accepted
Consequence	faa : reviewed incident with flight crew
Supplementary
Problem Areas	ATC Human Performance Flight Crew Human Performance
Primary Problem	Flight Crew Human Performance

Narrative:

Las vegas approach ATC is under the wrong impression that wake turbulence separation intervals specified in the aim; and repeated in our air carrier's fom only applies for IFR operation and not for VFR. This was stated to me by its operations manager mr X. ATC directed my break out of the final approach segment after I insisted the need to reduce airspeed to obtain required spacing behind a B757. That aircraft was approaching the parallel runway (1L) which is separated less than 2500 ft from my assigned runway (runway 1R). The breakout action cost our air carrier 1500 pounds of fuel and 10 mins operating time. The las vegas ATC operations manager; mr X; said 'I needed to request wake turbulence separation early.' wake turbulence separation standards are normally automatically applied by most ATC; irrespective of WX; for landing and departing aircraft using the same runway; parallel runways separated by less than 2500 ft; and for some situations; crossing runways. The pilot does not need; or is required; to request the separation. I was advised the B757 would be on the parallel runway; but I did not know if that aircraft would be in front; behind; or abeam my plane. In addition; I was not yet assigned a landing runway. The moment I was assigned a turn to base leg; I realized the situation and notified ATC of the conflict. ATC cleared me for a visual approach and refused my need to reduce below the assigned speed of 170 KTS to obtain separation. So; what is going on here? Why was I sequenced off the final approach segment due to my need to operate a safe flight? Mr X said I had aircraft behind mine. Since when is a lead aircraft routed to accommodate following aircraft? Can't the following aircraft also slow or delay its turn to base leg? Has the wake turbulence phenomenon of the last 40+ yrs gone away? Does it only happen in IFR conditions? The ironic part of my phone conversation with mr X was his comment that 'other pilots accept reduced separation behind B757's and heavies all the time.' he doesn't understand the problem.

Original NASA ASRS Text

Title: ACR ON APCH TO LAS QUESTIONED ATC'S APPLICATION OF WAKE TURBULENCE SEPARATION PROCS.

Narrative: LAS VEGAS APCH ATC IS UNDER THE WRONG IMPRESSION THAT WAKE TURB SEPARATION INTERVALS SPECIFIED IN THE AIM; AND REPEATED IN OUR ACR'S FOM ONLY APPLIES FOR IFR OP AND NOT FOR VFR. THIS WAS STATED TO ME BY ITS OPS MGR MR X. ATC DIRECTED MY BREAK OUT OF THE FINAL APCH SEGMENT AFTER I INSISTED THE NEED TO REDUCE AIRSPD TO OBTAIN REQUIRED SPACING BEHIND A B757. THAT ACFT WAS APCHING THE PARALLEL RWY (1L) WHICH IS SEPARATED LESS THAN 2500 FT FROM MY ASSIGNED RWY (RWY 1R). THE BREAKOUT ACTION COST OUR ACR 1500 LBS OF FUEL AND 10 MINS OPERATING TIME. THE LAS VEGAS ATC OPS MGR; MR X; SAID 'I NEEDED TO REQUEST WAKE TURB SEPARATION EARLY.' WAKE TURB SEPARATION STANDARDS ARE NORMALLY AUTOMATICALLY APPLIED BY MOST ATC; IRRESPECTIVE OF WX; FOR LNDG AND DEPARTING ACFT USING THE SAME RWY; PARALLEL RWYS SEPARATED BY LESS THAN 2500 FT; AND FOR SOME SITUATIONS; XING RWYS. THE PLT DOES NOT NEED; OR IS REQUIRED; TO REQUEST THE SEPARATION. I WAS ADVISED THE B757 WOULD BE ON THE PARALLEL RWY; BUT I DID NOT KNOW IF THAT ACFT WOULD BE IN FRONT; BEHIND; OR ABEAM MY PLANE. IN ADDITION; I WAS NOT YET ASSIGNED A LNDG RWY. THE MOMENT I WAS ASSIGNED A TURN TO BASE LEG; I REALIZED THE SITUATION AND NOTIFIED ATC OF THE CONFLICT. ATC CLRED ME FOR A VISUAL APCH AND REFUSED MY NEED TO REDUCE BELOW THE ASSIGNED SPD OF 170 KTS TO OBTAIN SEPARATION. SO; WHAT IS GOING ON HERE? WHY WAS I SEQUENCED OFF THE FINAL APCH SEGMENT DUE TO MY NEED TO OPERATE A SAFE FLT? MR X SAID I HAD ACFT BEHIND MINE. SINCE WHEN IS A LEAD ACFT ROUTED TO ACCOMMODATE FOLLOWING ACFT? CAN'T THE FOLLOWING ACFT ALSO SLOW OR DELAY ITS TURN TO BASE LEG? HAS THE WAKE TURB PHENOMENON OF THE LAST 40+ YRS GONE AWAY? DOES IT ONLY HAPPEN IN IFR CONDITIONS? THE IRONIC PART OF MY PHONE CONVERSATION WITH MR X WAS HIS COMMENT THAT 'OTHER PLTS ACCEPT REDUCED SEPARATION BEHIND B757'S AND HEAVIES ALL THE TIME.' HE DOESN'T UNDERSTAND THE PROB.

Data retrieved from NASA's ASRS site as of May 2009 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.