I really hope Asobo ask some RL glider pilots. The problem with poor gliding implementations is you can compensate by having so much lift that no-one notices the instruments and flight performance are awful, so that’s a danger.
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E.g. AFSD shows all available data from the air and cfg file in FSX/P3D. There’s nothing hidden.
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In getting the aerodynamics right, achieving the correct glide performance without thrust is one of the few really important key items to design a high quality FDE.
If it’s a glider or an A380, it doesn’t make any difference.
Hence I was surprised about your comment about the ever increasing L/D ratio with decreasing speed in FSX.
I used to design aircraft for x-plane as well, but found it to be too limited concerning flight dynamics design.
Many years ago x-plane had an additional flap maker and I never understood why Austin removed it.
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Just did a bit more experimenting sloping a cub. There does seem to be some difference between the windward side and the lee side of the ridge but it’s by far not enough. The exact amounts are difficult to see due to being tossed around by the silly gusts.
So the hope is that the fundamentals are there, it just needs a lot more tweaking and adding stuff.
As to the updrafts “extending” under clouds. That would be the wrong way round right? It’s not the cloud that creates the thermal. Likewise there should be cloud formation on mountains when the air is shoved up past the dewpoint. Looking at how cumuli are scattered about in the mountains it seems somewhat random.
I’m not saying that asobo should already have implemented it, but if they have the fundamentals right this should clearly be the end goal and would be extremely cool. This would probably be incompatible with a simplistic weather dialog as we have it now.
Speaking of wind: The cub is stationary on the runway facing into a 45kts wind. Grass is blown around in large waves. Cub is not fazed at all, no shaking, not blown backwards, nothing. And now this: IAS shows 0kts, TAS 12kts (???)
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yes 100% agree. My bad writing.
I’ve slid down from a 3500 cloudbase and tried a thermal ‘save’ at 300 feet AGL… for 40 minutes. It was hot work, followed by the inevitable land-out in the field right underneath me. My ‘extending under’ concept was meant to be where I looked rather than how tall the thermal should be. I reckon anything 500’ AGL or under for the start of the thermal would be legit, as there are a negligible number of times you’d try and climb below that. (My 300’ failed save was a really bad example).
More complex for me is how a thermal slopes with wind… say a 5 knot thermal in a 5 knot wind, we know the thermal reaches into the cloud at the top, but is it sloped 45% (I don’t think so)? or maybe 20 degrees? Or does the collecting air collect more on the downwind end of the warmed area and go up vertically (i.e. move with the wind) once it’s detached from the ground? It seems in RL you can thermal directly under clouds from maybe 1000 feet below cloudbase, maybe? I’ve done it many times but can’t be sure. I do think when you drift out of a thermal while circling it pays to correct upwind which suggests some degree of slope downwind.
Actually I think I’m bundling two concepts here - one is how you circle to stay in the thermal during your climb, the other is how you align yourself to the cloud or another thermalling glider when you join from below.
I’ve seen a few theories, observations and diagrams about thermal structure. What it seems to boil down to is that it’s quite chaotic and no two thermals are the same - within certain limits. They don’t even have the courtesy to all spin in the same direction.
What remains is the question if a realistic (and stable) or at least plausible weather simulation with fine grained fluid dynamics is doable (funding by MS?) in the context of a mere “video game”.
Local weather or global weather? Server- or Client-Side? How is it replicated in multiplayer so we all have the same thermals?
A simultaneous virtual online gliding competition. I hope I get old enough to see it…
My 2 cents - I don’t think traditional ‘fluid dynamics’ has a chance of working in a flight simulator (i.e. the ‘traditional’ Navier-Stokes, even if the cunning plan is to pre-compute it all and just download the result) so you have to have an efficient approximation.
For ridge lift this is demonstrably doable and the same technique is implemented in FSX (CumulusX) and X-Plane, but I’m not sure what’s in FS2020 - you could in theory pre-calculate all the fluid flow for every wind speed and direction, and then look that up, but that technique hits a massive granularity constraint (even if you model the air as 100m cubes) so the ‘approximate’ method wins out because it effectively turns a 4D problem into a 1D problem (look mostly up/down wind from the aircraft) which can be calculated per-frame extremely quickly with an arbitrarily high resolution (because you only calculate the ridge lift at the point of the aircraft, not in the entire volume).
Thermals is another gig entirely but I’m sure will still be a hard-coded approximation - the great news is Asobo have clearly modelled the upflow at each of their clouds, hence the time-lapse animation - this should then actually be easier than the ridge lift with a ‘function’ for height and wind direction and x,y offset that tells you the lift at any point relative to that cloud (or… maybe they’ve already coded the ‘source’ of the lift and the cloud position is programmed relative to that, but I doubt it, hence my inverted logic earlier). This is what’s baked into CumulusX in FSX. The rookie error is to imagine you calculate the vertical air movement everywhere (i.e. traditional fluid dynamics) and then pick out the one place the plane happens to be - you start with the position of the plane as a given and just calculate that spot, making big compromises on the actual air movement as a result. This is a all a long way from FSX stock thermals which are typically large vertical cylinders with fixed lift hard-coded in a profile from center to edge.
FS2020 seems well placed to support multi-player with common time and weather to all players, and so long as Asobo don’t throw this away with the thermals we’ll be fine. It would be good to confirm multiplayer clouds are identical - if not we’re stuffed.
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I’ve done some testing of ridge-lift & it does appear to be present, as is sink on the leeward side of the ridge…
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Looks like we can “up vote” these wishlist suggestions now. Scroll up to the top of this post & give it a vote.
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I miss Gliders too. We need Gliders in this Game!
I thought you guys might like to see it is actually possible to glide in MSFS. Well sort of. It’s a beginning at least but yeah, it would be great to have Asobo & Microsoft get behind this too.
This will be the last video I post in this thread (not really the place for it). But I know you folks would want to see a glider actually in the sim. I’m so excited, this is going to be amazing.
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I think Asobo have made the same mistake as every other sim. They should have started out by sending their devs on a meteorology course. Basic schoolboy met is that cumulus clouds are formed when rising currents of warm air (thermals) cool down and - at the dew point, form water droplets. The reasons why some parts of the terrain heat up quicker than others are also well know (and can easily be googled).
So get the motion of the air moving correctly from the ground up and everything else will fall into place. What goes up must come down and it is this rising and sinking of warm and cool air that creates the turbulence. Its not a question of - oh we’ll shake the aircraft around a bit to simulate turbulence. Turbulence is an effect of some air movement - not a cause. Likewise the effect of wind being deflected upwards on a hill or mountain slope. The updraft is an effect not a cause.
I do hope someone from Asobo reads this sooner rather than later so the met in MSFS can be fixed and become more realistic. The more they get the met right, the less the aircraft devs will need to do - because if the aircraft geometry is correct, the damned things should just fly.
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Definitely, with weather and atmosphere properly modeled its hard to believe this didn’t make the list from day 1.
I guess with some aircraft in the sim that you could actually experiment with gliding up to a point with the engines cut. Certainly nothing like the best man-made gliders but almost as good as a bird! The Icon A5 has a 9:1 glide ratio. Couldn’t find the glide ratio for the Zlin Shock Ultra but since it has a lower stall speed than the Icon A5, it might have an even better glide ratio. That’s something that they should give in the sim specs since if part of the fun of the sim is to simulate engine failure, etc., knowing your plane’s glide ratio might be the difference between life and death in the sim (the Bridge Too Far syndrome).
If we’re into regular gliders, why not hang gliders, paragliders, wingsuit gliding, and sky diving! Theoretically, with a VR headset and hand and ankle/foot controllers you could control your descent and in a drone camera view even see a good simulation of yourself virtually flying through the air with associated body movements, etc.
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+1 for gliders. It was also on the pre-release development roadmap wishlist iirc.
An improved wind model with properly simulated gusts, thermals from sampling ground layer types, additions of birds soaring and various glider planes seems like a perfect official DLC to me. Releasing the improved wind model as a free DLC while the tailored gliding experience requires a purchase. I can see that.
A properly simulated atmosphere with correct gusts, thermals & fluid dynamics over terrain would benefit all types of aviation, not just glider flying. That should be part of the base simulation in my opinion. But I don’t mind paying for a DLC that includes a glider, a winch launch system & the ability to summon a towplane.
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Yeah, I absolutelly agree with what you are saying. With the complex aerodynamics the game has, its have been such a bad thing not even adding 1 single glider to the game, even without thermals. I hope we can thermal and ridge soaring with gliders soon.
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how do you get into the air? Oh, I don’t have the FSX though.
Select your airfield in the map then click next to it to make a custom start position, you will start in the air as if you just came off the winch or aero-tow.
Cheers
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You can also switch aircraft while flying using the DevMode menu. Start at an airport using any of the default MSFS aircraft. Fly up to altitude, then using the DevMode menu choose your glider from the list & hit load. Note the glider will spawn in the air with zero forward speed so be prepared to do a stall recovery. Not ideal but it’s another option we can use.
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