Atlantic Routings

[Akrotiri bad boy]

I hope someone can answer the following query.

I recently flew from LHR to Las Vegas and Back. Westbound we flew up country before turning outwards over Mull and the Hebrides. On the return we entered UK airspace over the Bristol Channel. Was the different routing down to traffic, met. conditions or routine procedures?

I'd be grateful for any answers.:8

[Midland 331]

North Atlantic Tracks - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/North_Atlantic_Tracks)

[jackieofalltrades]

Largely the routeing is down to weather. Specifically the jetstream over the Atlantic. This tends to flow West to East, and so the aircraft flying towards North America tend to fly more northerly tracks to avoid flying into the very strong headwind of the jetstream.
Travelling in the opposite direction towards Europe, the aircraft "want" to fly with the jetstream, which are more typically southerly tracks. Hence you leaving the UK over the Hebrides and returning via Bristol.

It's not entirely as simplistic as that, but the position of the jetstream over the Atlantic will largely dictate the track you'll fly.

Try North Atlantic Tracks (http://occ.ivao.ca/airspace) for further info.

[Suzeman]

See the actual tracks day to day here

westbound http://www.jetplan.com/tda/west.html

eastbound http://www.jetplan.com/tda/east.html

Put the cursor over "final" to reveal the tracks. Jetstream is shown in yellow

Suzeman

[donnlass]

Are the red dotted "racecourse patterns" shown holds?

[Double Hydco]

No, they are areas of forecast turbulence. The numbers at the end of the arrows are the upper & lower levels (ie FL350 to FL250).

[Groundloop]

Largely the routeing is down to weather. Specifically the jetstream over the Atlantic. This tends to flow West to East, and so the aircraft flying towards North America tend to fly more northerly tracks to avoid flying into the very strong headwind of the jetstream.
Travelling in the opposite direction towards Europe, the aircraft "want" to fly with the jetstream, which are more typically southerly tracks. Hence you leaving the UK over the Hebrides and returning via Bristol.

There is no "tend to fly northerly tracks" westbound and "more typically southerly tracks" eastbound. The jetstream can change position quite quickly so one day westbound tracks could be quite far north but in the next day or so they could be much further south - with eastbound tracks doing the opposite.

[TopBunk]

The current tracks in detail:

Eastbound NAT Tracks (20111003)
031302 CZQXZQZX
(NAT-1/2 TRACKS FLS 320/400 INCLUSIVE
OCT 04/0100Z TO OCT 04/0800Z
PART ONE OF TWO PARTS-
U STEAM OYSTR 55/50 56/40 57/30 57/20 SUNOT KESIX
EAST LVLS 320 330 340 350 360 370 380 390 400
WEST LVLS NIL
EUR RTS EAST NIL
NAR N153C N155A-
V REDBY CARPE 54/50 55/40 56/30 56/20 PIKIL SOVED
EAST LVLS 320 330 340 350 360 370 380 390 400
WEST LVLS NIL
EUR RTS EAST NIL
NAR N137B N141B-
W YAY HECKK 53/50 54/40 55/30 55/20 RESNO NETKI
EAST LVLS 320 330 340 350 360 370 380 390 400
WEST LVLS NIL
EUR RTS EAST NIL
NAR N123A N129B-
X DOTTY CRONO 52/50 53/40 54/30 54/20 DOGAL BEXET
EAST LVLS 320 330 340 350 360 370 380 390 400
WEST LVLS NIL
EUR RTS EAST NIL
NAR N107B N113B N115B-
Y CYMON DENDU 51/50 52/40 53/30 53/20 MALOT GISTI
EAST LVLS 320 330 340 350 360 370 380 390 400
WEST LVLS NIL
EUR RTS EAST NIL
NAR N91B N97B N99A-
END OF PART ONE OF TWO PARTS)
031302 CZQXZQZX
(NAT-2/2 TRACKS FLS 320/400 INCLUSIVE
OCT 04/0100Z TO OCT 04/0800Z
PART TWO OF TWO PARTS-
Z YQX KOBEV 50/50 51/40 52/30 52/20 LIMRI XETBO
EAST LVLS 320 330 340 350 360 370 380 390 400
WEST LVLS NIL
EUR RTS EAST NIL
NAR N75B N83B N85A-
REMARKS:
1.TMI IS 277 AND OPERATORS ARE REMINDED TO INCLUDE THE TMI NUMBER AS
PART OF
THE OCEANIC CLEARANCE READ BACK.
2.CLEARANCE DELIVERY FREQUENCY ASSIGNMENTS FOR AIRCRAFT OPERATING
FROM KENKI TO BOBTU INCLUSIVE:
KENKI TO GRIBS 132.02
MIBNO TO LAKES 134.2
MOATT TO SCROD 126.025
OYSTR TO YAY 135.45
DOTTY TO CYMON 135.05
YQX TO YYT 128.45
COLOR TO BOBTU 119.42
3.OPERATORS ATTENTION IS REQUIRED TO REVIEW SECTION 9.2 OF THE GANDER
OCEANIC CLEARANCE DELIVERY CREW PROCEDURES LOCATED AT
ICAO EUR/NAT Office (http://WWW.PARIS.ICAO.INT) NAT OPS BULLETIN 2010-008. THE OEP ESTIMATE
USED BY ATC WHEN PRODUCING AN ELECTRONIC OCEANIC CLEARANCE IS
LOCATED NEXT TO THE OEP, THIS TIME MAY NOT COINSIDE WITH
THE RCL ESTIMATE, BUT SHALL BE USED FOR CONSIDERING TIME REVISIONS.
4.OCEANIC PROCEDURES IN THE EVENT OF A GANDER ACC EVACUATION ARE
PUBLISHED IN AIP CANADA ICAO PART 2 ENR 1.8.
5.EIGHTY PERCENT OF GROSS NAVIGATIONAL ERRORS RESULT FROM POOR
COCKPIT PROCEDURES. ALWAYS CARRY OUT PROPER WAYPOINT PROCEDURES.
6.OPERATORS ATTENTION IS DRAWN TO NOTAMN 110176 CZQX GANDER FIR RE:
THE
ESTABLISHMENT OF TALGO AS AN EASTBOUND OCEANIC ENTRY POINT.-
END OF PART TWO OF TWO PARTS)
Westbound NAT Tracks (20111003)
032111 EGGXZOZX
(NAT-1/3 TRACKS FLS 310/390 INCLUSIVE
OCT 04/1130Z TO OCT 04/1900Z
PART ONE OF THREE PARTS-
A AGORI 61/20 64/30 65/40 65/50 64/60 KAGLY TEFFO
EAST LVLS NIL
WEST LVLS 310 320 330 350 360 370 380 390
EUR RTS WEST NIL
NAR NIL-
B VENER 57/20 60/30 61/40 61/50 59/60 LAKES
EAST LVLS NIL
WEST LVLS 310 320 330 350 360 370 380 390
EUR RTS WEST NIL
NAR N412B N414C N424E N428C N432B N434C-
C DINIM 50/20 47/30 45/40 44/50 BOBTU JAROM
EAST LVLS NIL
WEST LVLS 310 320 330 340 350 360 370 380 390
EUR RTS WEST NIL
NAR N52E N54E-
D SOMAX 49/20 46/30 44/40 43/50 JEBBY CARAC
EAST LVLS NIL
WEST LVLS 310 320 330 340 350 360 370 380 390
EUR RTS WEST NIL
NAR N40E N44B-
END OF PART ONE OF THREE PARTS)
032111 EGGXZOZX
(NAT-2/3 TRACKS FLS 310/390 INCLUSIVE
OCT 04/1130Z TO OCT 04/1900Z
PART TWO OF THREE PARTS-
E BEDRA 48/20 45/30 43/40 42/50 42/60 DOVEY
EAST LVLS NIL
WEST LVLS 310 320 330 340 350 360 370 380 390
EUR RTS WEST NIL
NAR NIL-
F OMOKO 48/15 47/20 44/30 42/40 41/50 41/60 JOBOC
EAST LVLS NIL
WEST LVLS 310 320 330 340 350 360 370 380 390
EUR RTS WEST NIL
NAR NIL-
G ETIKI 47/15 46/20 43/30 41/40 40/50 40/60 SLATN
EAST LVLS NIL
WEST LVLS 310 320 330 340 350 360 370 380 390
EUR RTS WEST REGHI
NAR NIL-
H SEPAL 46/15 45/20 42/30 37/40 33/50 AMENO
EAST LVLS NIL
WEST LVLS 320 340 360 380
EUR RTS WEST LAPEX
NAR NIL-
END OF PART TWO OF THREE PARTS)
032114 EGGXZOZX
(NAT-3/3 TRACKS FLS 310/390 INCLUSIVE
OCT 04/1130Z TO OCT 04/1900Z
PART THREE OF THREE PARTS-
J DETOX 41/20 41/30 40/40 39/50 SOORY
EAST LVLS NIL
WEST LVLS 330 350 370 390
EUR RTS WEST
NAR NIL-
REMARKS.
1. TMI IS 277 AND OPERATORS ARE REMINDED TO INCLUDE THE
TMI NUMBER AS PART OF THE OCEANIC CLEARANCE READ BACK.
2. FOR STRATEGIC LATERAL OFFSET AND CONTINGENCY PROCEDURES RELATED TO
OPS IN NAT FLOW PLEASE REFER TO THE NAT PROGRAMME COORDINATION WEB
SITE AT ICAO EUR/NAT Office (http://WWW.PARIS.ICAO.INT) CREWS ARE REMINDED TO OFFSET AT AND NOT
BEFORE THE OCEANIC ENTRY POINT AND MUST RETURN TO THE CENTRELINE
PRIOR TO THE OCEANIC EXIT POINT.
3. EIGHTY PERCENT OF GROSS NAVIGATION ERRORS RESULT FROM POOR COCKPIT
PROCEDURES. ALWAYS CARRY OUT PROPER WAY POINT CHECKS.
4. OPERATORS ARE REMINDED THAT THE CLEARANCE MAY DIFFER FROM YOUR
FLIGHT PLAN, FLY YOUR CLEARANCE.
5. UKAIP.ENR2.2.4.2 PARA5.2 STATES THAT NAT OPERATORS SHALL FILE
PRMS.
6. AT NEW YORK ATC REQUEST ROUTE TO FILE FOR KIAD:
ACK HTO RBV HOUTN V457 LRP HYPER2?
OR BOJAN SIE ENO V268 BAL V44 MRB AML.
7. AT NEW YORK ATC REQUEST ROUTE TO FILE FOR KPHL:
BOJAN WICKE SIE VCN JIMGE2?
OR ACK HTO J121 BRIGS VCN8?
OR LINND OWENZ DRIFT BRIGS VCN JIMGE2-
END OF PART THREE OF THREE PARTS)

[WHBM]

There is no "tend to fly northerly tracks" westbound and "more typically southerly tracks" eastbound. The jetstream can change position quite quickly.
I'm sure it does move around and so therefore do the optimum tracks. However, based on the very empirical evidence of a large number of North Atlantic crossings over many years I would say it is certainly true that my westbounds have tended to be, on average, further north than eastbounds, it's something I take notice of. Extremes have been westbound London to Miami routing over Newfoundland, and eastbound San Francisco to London also routing over Montreal and Newfoundland.

I do see that, looking at the links above, today the opposite is true.

[jackieofalltrades]

There is no "tend to fly northerly tracks" westbound and "more typically southerly tracks" eastbound. The jetstream can change position quite quickly so one day westbound tracks could be quite far north but in the next day or so they could be much further south - with eastbound tracks doing the opposite.
Yes, the jetstream does vary day to day, but in my experience, actually working at the air traffic control centre that handles Trans-Atlantic crossings, in general, the westbound tracks do tend to be more northly to the eastbound tracks. Obviously, this is not set in stone, and like commented above, today is an example where the eastbound tracks are in fact northerly of the westbounds.

[WHBM]

The "westbound more northerly than eastbound" standard is also true elsewhere. New York to Tokyo tends to route westbound pretty much over the North Pole (so to be precise, more northbound, then southbound), whereas the return from Tokyo is more commonly across the North Pacific and over Alaska/Yukon etc.

[crispey]

Today's VIR 086 from LAS to MAN approached UK from over the Outer Hebrides.On the upper air charts it looks like a good NW jetstream at over 100k from south of Greenland to UK

The ANZ 002 frorm LAX- LHR this morning approached via Belfast.