Here’s my main concern with the MSFS thermals. I think Seb Wloch is doing a great job but it’s clear he lacks the first-hand familiarity with thermals that only comes with real gliding experience and the slightly confused answers regarding lift/thermals in the dev updates makes me anxious (but HUGE credit to Asobo for doing the Dev Updates in the first place). How thermals under decent Cu’s ‘feel’ to me is as in this picture:
i.e. the rising air ‘collects’ near the ground (and you feel a thermal ‘inflow’ breeze if you’re on the ground, but that’s very much a secondary effect compared to the soaring aspects I care about). Then the air rises in a relatively well organised column which if you can find that and circle in it, you’re gliding like a boss. A significant art in soaring is finding the core of the thermal under a Cu, and not arriving at the cloud when the thermal that was definitely there when you set off is dying a slow death when you get there. It’s worth noting that the column of rising air can weight 100,000 TONNES, so nothing is going to stop that juggernaut until it decides for itself although conditions (i.e. the temperature difference between the ground and aloft) may mean the air rises slowly or quickly.
Currently the ‘thermals’ (I know Asobo say they’re not implemented yet) feel more like this picture:
i.e. the lift feels scattered and scratchy underneath the cloud, and spread in a lot of small pockets that are currently capped at the current limit of approx 5 knots / 2.5 m/s. This is less of a concern if removing the ‘cap’ means there IS a core in there somewhere at 10 knots, and the other noise stays at 5 knots (although that wouldn’t be great) but I suspect with the current implementation all the values would just scale up.
I’m not knocking Asobo - they’re doing a great job, and we’re fortunate to have this commitment to connect the lift to the clouds in a fundamental way. My example above is to highlight something basic that soaring pilots will ultimately care more about than quite a few more subtle points that have been raised over the past few months.
showcase of gliders and helicopters at the gamescome and some short words about updrafts and they mention Flightsim Studio again and the fact that they have real life glider pilots in their team
I’m wondering if this visualisation tool has more options, because we saw these lines near the ground in the past, but the interesting part, what’s gonna happen between these lines up to the clouds and above… they never showed that.
Like will it be possible to see the whole airflow and possibly even thermals?
I think that’s where the big local CFD, which is currently in research, comes into play.
Good job Homie. The visualisation tool is really informative - impressive they can do that quickly enough for a real-time sim, I wonder how they do that.
The visualisation seems to fit my guesswork - there doesn’t seem to be a concept of the lift forming more concentrated columns (i.e. thermals) as it leaves the ground, rather there are wide areas of lift rising with parallel stream lines. I mean the lift on the plains in the background, rather then what might be a sun-facing slope in front of the glider. Hopefully the experienced soaring test pilots FlightSim Studios are using will be aware of the potential issue.
A possible simplistic compromise would to make the diameter of the lift areas smaller and make the lift stronger. Or maybe the lift near the boundaries of the ground area only rise to a shallower height than the lift lines nearer the center would give a similar effect.
My estimate for the diameter of an example thermal would be a ‘core’ diameter of maybe 250m, and less strong rising air wrapped around that (500m maybe?). (The reasoning for that calculation is I’ve timed a RL core thermalling turn in my ASW24 at 24 seconds, flying at say 60 knots, which gives me a circumference of that circle at 740m, so a diameter of 235m. Experience says you have to turn about that tight to stay in the core of some thermals. Approximate figures obviously and YMMV. Weaker thermals can definitely be more spread out.) Under Cu’s there’s enough lift that most pilots can stay aloft, but the best pilots find the core, climb fastest on average, and win the comps.
The area covered by the lift in the background of the screenshot is much larger (1500m?). I agree if this sorts itself out on the way up to cloudbase we’ll be ok.
I rewatched one Q&A from march, the way Seb explains the problems with the current airflow system sounds like what you are describing.
And the solution to that is gonna be the big local CFD, from what he describes, the result of that basically resembles your picture of what a thermal should look like. (not gonna be in SU10)
well done again Homie - it sounds like you’re exactly right & Seb talks there about the rising air ‘not combining’, and even back in March he was saying ‘not Update 10, maybe 11’ for the improved development.
Per feedback, turbulence & drafts have been reduced by 90% at 0kts wind speed and 50% at 1kts wind speed (no change above 3kts wind speed). turbulence and drafts have also been reduced by 50% at high altitudes
Sometimes I wonder if there is some sort of parallel Forum where they get their feedback from or they just simply made that up while ignoring the actual feedback in the Forum…
I think the idea is that people who don’t like turbulence can turn wind down in pre-sets to get rid of it if they want to whilst live weather remains un-touched.
Some must be having a different experience to others though. I have seen people saying turbulence makes flying impossible in light aircraft but I have never had this issue. It’s a bit wobbly sometimes on approach but never so bad that I could not touch down.
The issue here is thermals, which are critical for soaring, are now disabled if the WIND is below a certain speed. You could argue there’s a real-world justification for reducing ‘gusts’ and ‘turbulence’ (if that exists in MSFS) as the wind dies down, but thermals (which arise from solar heating of the ground) are at their best with low wind.
Odd timing before the gliding update - we soaring pilots just need to ensure we have some wind to enable thermals even flying a flat cross-country. Not a major drama but odd to link it to wind speed all the same as if the thermals were linked to the wind in some way. It did seem at the beginning Asobo tended to think ridge lift and thermals were all similar ‘updrafts’ but surely we’ve moved on a long way since then?
In summary I’d say at low wind speed, limiting gusts is fine, limiting “turbulence” is fine, limiting ridge lift is fine, limiting thermals is a mistake.
SU10 significantly ruined thermals compared to what was in SU9.
The restriction of the maximum vertical speed of the thermal in 500ft/min has not changed. In real life, this speed can reach 2500ft/min.
The dependence of the vertical velocity of the termal on the density of the clouds has changed. In general, this is not very fundamental, since the density of the clouds can be increased without a deterioration in the appearance of the clouds. It is necessary to increase the density of the clouds in old weather presets.
The influence of the height of the cloud layer has changed, has become more proportional. For the proper operation of the old weather presets, it is advisable to increase the height of the upper boundary of the cloud layer.
The effect of air temperature in the Earth has changed, became more proportional. For the proper operation of the old weather, it is advisable to increase the air temperature.
The influence of the speed of horizontal wind has changed. For the proper operation of the old weather presets, it is advisable to set the wind speed above 2 KTS.
It is very wrong when thermals continue to actively act at the height inside the clouds and even significantly higher than the clouds. It was in SU9, it remained in SU10. I managed to easily gain a height in the thermal above the cloud above 30,000FT.
In the SU9, the dependence of the vertical speed of the termal on the time of day was well implemented. The maximum activity of thermals corresponded to the time 13:00 - 16:00 day. In SU10, this dependence has completely disappeared, now thermals are equally active day and at night.
Hi your analysis is definitely genius, but it’s possible we need to separate what we’re looking at into two different parts:
(a) things that might be ok with the 500fpm cap removed - in this case we do want the thermals to vary between clouds and varying based on cloud density (which gives us an opportunity to tune the thermals) and cloud height (which gives you at least one way to see in the sim which thermals might be stronger - not perfect but the idea of optimising your cross-country speed by picking the better thermals is a good one).
(b) things that suck, like no varying thermal strength with time on blue days (blue days suck anyway in RL, but it seems odd the MSFS thermals don’t vary with time then). I’m a bit confused where your top-right comment seems to suggest time of day/month isn’t used at all in any thermals, which would make the blue day analysis irrelevant? Thermals dying when the wind dies does suck IMHO but at least it’s at very low wind speed which is manageable. And the height the lift goes to seems complicated to fix as the SU10 patch seems like a bodge - I love climbing in clouds though so I’d be keen we keep that (I could soften the wind sound of the AS33 when you’re ‘in cloud’ if that variable works which would be awesome).
Definitely awesome analysis & we do seem to have gone backwards rather than forwards. I’m hoping this is temporary until the gliding update though.
What can you expect when you get people saying things like “constant turbulence”?
I flown in Spain, Italy, Australia, UK, Norway, Austria, Denmark, in the 172 and TBM and I have NEVER seen this “constant turbulence” that some seem to keep harping on about. But Asobo seem to take notice of those sort of exaggerated opinions and are trying to find ways of giving people some sort of control over it.
