Just flying around when I noticed this: Whenever I hit heavy tailwinds, like the ones going across the pond from the US to Europe (I hit around 82 kts tailwind on my last crossing), the airspeed will slowly drop. At the same time, the N1 speed remains constant and so does the throttle!Does anyone have any clue as to WHAT I can do to fix this? Or do I just have to settle for Europe-US flying (and skip the returns) for the time being?

You provide very little data, so its difficult to help you. But, it sounds like you may be bumping up against the thrust limits...which might result from flying too high for your weight (try a step climb)...bad temperature aloft data (bogus TAT readings yield bogus thrust limits)...Try using the thrust control panel to select continuous TOGA thrust while in flight - this will make the full potential of the throttles available to you while in flight.Cheers,J

Seems to me many pilots would love to have a 82 kts tailwind. Makes for increased fuel economy, less time enroute. You said your airspeed slowly drops, so that would mean the tailwind is slowy increasing. Although you'll need to adjust your airspeed to keep from stalling, I don't see that this would be a huge problem.I'm not an expert or anything, so if thats incorrect, I'm sure someone will slap my hand (lol).-=MB=-

I think what you hit was wind shear caused by flying from one geographical area to another. As you cross a boundary between two weather stations, the wind speeds, and more importantly, direction can change rapidly. I've seen FSMeteo change a 100kt aloft wind by 120* or more. If you go from a headwind to a tailwind rapidly enough, and you're cruising at high power settings (typical), the A/T will not have enough reserve power to maintain airspeed, possibly leading to a stall.Since changing my weather smoothing in FSUIPC, I haven't suffered from this problem. I cannot remember my exact settings, but I think I have 5 seconds/degree and 5 seconds/kt wind change set in FSUIPC.Lee Hetherington (KBED)

Everyone loves a tailwind!http://www.geocities.com/anthonyj_au/Photo..._flightdeck.jpghttp://www.geocities.com/anthonyj_au/Photo_Pages/ZXD.html

Sheesh! That's one nice tailwind. Wonder what it would be like going in the opposite direction.

Hi all!Thanks for the input & sorry for not adding the necessary data, but I was just frustrated as I had spend a good deal of time finding the correct charts, setting up the FMC etc.(read: brewing a pot of coffee!) just to watch the whole thing drop dead since it stalled before reaching ToC. I'll see if I can add what I recall from the short flight:You provide very little data, so its difficult to help you. But, it sounds like you may be bumping up against the thrust limits...which might result from flying too high for your weight (try a step climb)...Not really, I was in continous climb with the thrut limits at around 90-ish with N1 at around 80% (it tried to climb, but it couldn't). The Max FL was 400, the optimum 340 and my targeted FL was 370.bad temperature aloft data (bogus TAT readings yield bogus thrust limits)...Try using the thrust control panel to select continuous TOGA thrust while in flight - this will make the full potential of the throttles available to you while in flight.Might be worth trying, I'll see what happen next time!You said your airspeed slowly drops, so that would mean the tailwind is slowy increasing. Although you'll need to adjust your airspeed to keep from stalling, I don't see that this would be a huge problem.The problem is that the airspeed drops a lot! We're talking around 180-160 kts, and by then the nose has rised to 8-9 degrees, which I can't imagine being right.I think what you hit was wind shear caused by flying from one geographical area to another. As you cross a boundary between two weather stations, the wind speeds, and more importantly, direction can change rapidly. I've seen FSMeteo change a 100kt aloft wind by 120* or more. If you go from a headwind to a tailwind rapidly enough, and you're cruising at high power settings (typical), the A/T will not have enough reserve power to maintain airspeed, possibly leading to a stall.I was monitoring the wind arrow, as well as talking to a company pilot going the opposite way (to ORD), and he said that the winds were head on all the way. And sure enough, after doing the right hand 90 turn coming out of DTW on the St Clair DP, YXU trans, the wind gauge remained constant. Yes, there were minor changes, but no 120* changes liek you mentioned.Ah well, since the weekennd is coming up, I might try again and see what happens. Not to mention take plenty of screenshots, to be able to explain what happens!

hrrmmm, scrapes throat...lot's of money to the airline... lollotsa fuel of course...

Using FSMeteo?If so, disable upper wind gusts in the meteo options.If already said, disregard.

I'm using ActiveSky (haven't got the funds for FSMeteo, besides I've got other things to buy).

Another non-expert jumping to help Kasper :-)First I would look at Lee's suggestion of reducing the rate of change of wind speed and direction.I had similar problems when the PSS 'Bus came out and a rl pilot said that the rate of change had more effect on the A/T than the actual wind speed.I would go from 'knots/sec' to 'sec/knot' in increments until the a/c can cope with strong head/tail winds, certainly 100+ kts winds are not uncommon. I think my settings are around 2-5 sec/kt.You state that optimum FL was FL340, target FL370 but do not say at what level you experienced loss of airspeed.If you were above FL340 then I suspect you were rushing the climb and should have levelled off at FL340 until lighter and then step climb up to FL370. If however you were below FL340 then that theory is blown out of the water :-lol Rgds

Hi Kaspar,Just had the same problems with a flight from EGLL to EDDF. I had 80+ knts of tail over belgium and watched the airspeed drop rapidly.the FMC said I was in the optimal zone i.e. fl370 and the plane was really light: ZFW 246.5lbs, fuel 45lbs.This has only happened with the new active skies, but it has happened on both my 767-300ER and my 'busses.Ended up dropping to FL350.to correct the problem, but I suspect this might be quite wide spread.Cheers,Chris WillisBAW976,www.bavirtual.co.ukwww.speedbirdonline.co.uk

good evening allin fact, the Indicated Airspeed drops as we need to add to our IAS the winds, if blowing from 180

OK guys,Let's just be clear about this. I am getting the feeling there is some misunderstanding about how this works IRL.n the sim, if you do not have FSMeteo or whatever weather program you use set to have a relatively slow wind transition (mine is set for 1 knot or deg every 5 seconds) you may get a rapid change in IAS as the new wind data kicks in because the airplane cannot cope with that. These type of changes DO NOT occur IRL when flying in the high altitudes, even in the vicinity of a jetsteam. The transitions are much smoother. You may get some bumps, even a good jolt or two, but you will not see your airspeed change like you do in FS2K. Additionally, you do not have to change your cruise IAS just because you are flying with a headwind, crosswind or tailwind (you may wish to increase it slightly flying into a headwind to getter better range but that is a different issue). Your IAS should not and will not change just because the wind shifts from headwind to tailwind or whatever. With the exception of low altitude turbulence (gusts) or windshear the changes in wind do not occur faster that the inertia of the aircraft can compensate.If you are seeing a change in IAS as you cruise along, it is some FS2K wonky effect and in no way represents what would happen in the real aircraft at altitude. IRL you would cruise east at M0.80 (or so) and back at M0.80, regardless of the wind component (actually, you would modify your route to take advantage of the tailwind going east and to avoid the worst of headwind coming west).Kevin in CYOW

Seeing that I'll be taking part in a flyin this evening, using ym trusty PIC/POSKY3 merge, I'll boot up FSScreen and see if the same thing happens.Oh, and nice tailwind (153 kts, sheesh!)