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pierre95870

High altitude odd temperatures

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HiAfter upgrading ASE to AS2012, I flown a long haul from EDDK to WBSB (PMDG MD-11).during this flight I read on the FSFK flight plan at 33000ft a temperature of 15°C two times between many -55°C/-60°C.Could you explain this odd phenomena?Best RegardsPierre

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I have the same trouble when flying the SR-71 above 70K ft in certain areas of the world. These troublesome areas include:North-Central Atlantic Ocean half-way between waypoints 50151 and COLORUS Rocky Mountains states.Directly over the entire Newfoundland area of Canada.When flying these areas, the temperature rapidly flips between -90 Deg C and +15 deg C.For one, the temperature ASE sets for altitudes between 60 and 80K ft is WAY too cold by at least 20 degrees from real world average values.Two, the extreme switch between these two extreme temperatures (when displayed in Weatherset, 15C shows up as the next to top temperature layer and -70C as top)my plane gets swatted out of the air like a fly as the air speed drops and increases by 200 knots instantly. I tried the Beta and it has the identical problem.I would consider the upgrade to 2012 if I knew the issues with high altitude temperatures and extreme high altitude temperature flipping was fixed.The easiest way to see the problem is to position over coastal Newfoundland and slew to over 70K ft. Another way is to fly my SR-71 model (fsx20121.zip available as "new" and "hot" files by Paul R. Varn on Flightsim.com library files.) By contrast, I find the default Jeppeson weather emulation in FSX much better behaved as far as correct temperatures at high altitude.-Pv-

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Hi, I have AS2012 and it worked fine some days. However, a few days ago it started to show the following problem: when I am making a simulation having São Paulo (SBSP) as destination, for example, executing the STAR at FL 240, when I tune the ATIS's frequency, it shows wind direction and temperature completely different from what is showed at Xgauge and at METAR. ATIS says that the wind of 13kts on 290º and temperature -20ºC, while XGauge indicates the correct such as 180º at 9kts and 30ºCAs I descend the flight, temperature and wind goes to the real values showed at Xgauge. Also, when I'm stopped at parking ATIS still shows different wind and 20 degrees more than the indicated at Xgauge and METAR. This causes continuous changes of the used runway.Does that have a solution?

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I've been complaining about this issue for weeks. Now that my complaint is public, let's see how the response is after the holiday. I'm hoping one solution for the ultra-cold problem is they set the top layers in the -70C to -80C range instead of the -75C to -95C currently used above 60K ft, then fix the flipping between ground temperatures and current altitude over areas of the world where it may be that certain metar data or coordinate locations trigger a fault in the generator. There is also the possibility speed through the data locations contributes to the problem.Also, I have experienced the smoothest weather transitions in high speed aircraft when the FSX Graphics weather changes slider is set to low. It took a lot of experimenting to discover how to get ASE to set the slider in this position. When Dynamic Rate of Change was set to 10% or higher, ASE would use Medium which produced unwanted weather jumps. A setting of 6 or lower set the slider to none which depends 100% on the accuracy and effectiveness of the weather generator (ASE) to produce smoothing. A setting of 7% finally convinced ASE to set the FSX slider to Low which is my preferred setting. Time will tell if this is consistant and the slider will stay there. Although not 100% accurate at high speed and altitude, I would rather have morphed/stable weather at cruise than 100% accurate to metar reports which are highly unpredictable both in their consistency and accuracy and change too frequently at high speed. Using the Low setting allows FSX's internal "smoothing" to reduce the jarring effects of high speed cruise.Finally, I take issue with FSUIPC's so-called temperature and pressure smoothing settings. These checkboxes do not affect the weather environment the plane is flying in at all. Rather, they modify the weather data being sent to the panel instruments which (in the case of pressure smoothing) causes the outside environment pressure to be sent to the Altimeter in increments rather than suddenly. The environment pressure HAS changed unsmoothed and the plane has reacted to it with instant air speed changes. The Air Speed Indicator by responding slowly, gives the pilot the impression that pressure is changing smoothly because the altimeter is changing slowly and if flying under AP control, the AP reacts slowly. This is an illusion of smoothing, not the real thing. As far as temperature, I've seen no evidence in the couple years since this feature was introduced, there is any environment temperature smoothing at all.This is all to stress how important it is that the weather generator provide these very important temperature and pressure transitions, and do it well. Otherwise, it isn't going to happen. Allowing FSX's internal "smoothing" (taking the weather data given to it and reducing the rate at whihc is data is interpreted) is a poor, temporary, but necessary work-around.-Pv-Gustavo,Do the two pinned forum posts: "Stuck or invalid winds" or "AS2012 Hotfix" address your issue?-Pv-

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I forgot to mention the flips occur at the same times as or within 1 few seconds after the downloaded weather message appears on the screen. Also, the pressure gets set to 1013.0, regardless of what it was formerly. If in addition to the temp change, the pressure change is also large, the disruption is multiplied.-Pv-

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I test a new flight on polar route.Starting from Honolulu to Cologne.During first part of flight (30min after TO), at FL310 temperature suddenly rise to +45°C.EGT overheat and Fuel Flow with alarm flags.Must refresh AI three times to recover normal temp.Any idea to fix that?ThanksPierre

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