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Tight Slot
15th Aug 2008, 06:57
Hi guys, doing the planning for ETOPS trips, how many of us take into account the TAF and METAR reports (esp for Canada) and put the winds given into Mag winds with the varient? I knows loads of peeps that say yep the winds (given in TAFS or...) are ok with the runway avail at the alt airport. Some times it can be 30 degrees or more dif. I do the True to Mag change but lots of guys don't... Your thoughts?

TO MEMO
15th Aug 2008, 10:10
I do!

and everyone should! It makes little difference in europe, but in canda it actually might mean a different runway in use from that you`re expecting if not converting to mag degrees

Jimmy Do Little
15th Aug 2008, 17:49
I do it all the time, regardless of the country. True, it's a more pronouced degree of difference in the polar regions.

Hellenic aviator
16th Aug 2008, 08:03
I do all the time, especially when flying on a Polar route between JFK and HKG, I think about the runways of the ERAs (enroute airports) and which runway would I decide to use if I encountered an unexpected diversion.

BelArgUSA
17th Aug 2008, 11:43
Been absent from these areas since "last century" (shall I say 1992)...
xxx
Last time - 1992 - was dealing with flights from Anchorage or Fairbanks, to Keflavik/Prestwick, and dealt with airports such as Frobisher (Iqaluit), Sonderstrom or Goosebay. We navigated with the "plain triple INS", which gave us either true or magnetic on the HSI at the flip of a switch. We even had some of us using "grid nav" if necessary.
xxx
I landed a couple of times in Frobisher and Sonderstrom, was not a problem. I even recall a Northern Canada VOR which was even oriented to TRUE NORTH rather than having radials in magnetic, so we thought about QTE/QUJ, rather than QDR/QDM - Old fart here, cannot recall which VOR that was... maybe still there, and might confuse some of you guys...
xxx
Enjoy the penguins and the seals :)
Happy contrails

actu8
17th Aug 2008, 15:44
Airbus: If airport reference is degrees true (northern operations), PERF APPR page reference is "TRUE WIND".


If airport reference is degrees magnetic (most typical operations)
Insert degrees true wind from TAF, METAR reports into DESCENT WIND page.

eg. 270/15/1 This converts automatically on DESCENT WIND page to 270/15/GRND and is displayed on PERF APPR page in degrees magnetic.

Henry VIII
18th Aug 2008, 12:15
take into account the TAF and METAR reports (esp for Canada) and put the winds given into Mag winds with the varient? We do, and it should be one of the basic rules in planning, ETOPS or not.