FINALLY!!
MINE EYES HAVE SEEN THE GLORY OF THE COMING OF LORD
I’m making a plane game and this is a huge help… hopefully…
any idea when as to when this tech will be finished and released onto the platform?
great work, by the way.
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Im struggling to get an A350 at what I assume is equivalent (Maximum takeoff weight (1440 RMU) at equivalent gravity of 9.81 m/s) to takeoff at the correct v1 speed of about 165 knots. Ofc this may also be down to some confusion with if the Roblox provided unit conversions provided on Units are specfic to the default roblox gravity(192) or stay constant as conversions no matter the gravity set in workspace. Thanks
The same with the F15 ballast demo example. At what should be the AssemblyMass of 1750 RMU which is equivalent to the F15s 30,000KG Maximum Takeoff weight the F15 Cannot not lift off at all. This also with the 18,126 Rowtons of force which is equivalent to the f15s 25,000lbf thrust per engine. All this at 25studs/s or 9.81 m/s gravity.
Can you please share the function used for getting the wind speed based on height?
roblox units are really really weird. i may have not read your thing correctly but i found a tested conversion that is incredibly reliable, and will almost exactly scale up to real life units.
1 RMU == 1 KG
1 Newton == 3.5714 rowtons
now, how do i know 1 newton is 3.5714 rowtons? simple! In order to uphold a part with the mass of 1, presuming its 1 kilogram, you need 35 rowtons of thrust, so, if you divide that by 9.8, you get 3.5714 (plus a bunch of other numbers, if you need proof just look at the thread)
i tried this with an SU-25 with accurate engine thrust and what not and it had really good performance relative to the actual flight model irl.
your aircraft will be around 108,400 RMU (kg) in mass.
the A-350’s engines produce 375 kilo-newtons of thrust per engine (i got off of google, don’t quote me), so we convert 375 kn to newtons and we have 375000 newtons, so then we multiply by 3.5714 to get 1339275 as your thrust per engine. try it out! if it doesn’t take off, its probably something with ROBLOX’s aerodynamics, presuming that you are using correct wing area.
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Much thanks I will experiment and get back to here the one thing I do worry about is 108K RMU in mass is quite hefty. I was originally struggling with 11160 RMU(based off the unit conversion roblox gave) for takeoff with the current aerodynamic lift/drag rate.
good luck
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Yeh tested the above, same thing however i noticed with the units used from the Roblox units page I get a more attainable result, however the lift definitely is an issue, the wing etc is the correct length and width and the weight in the correct range.
Some ideal solutions as others have mentioned is a way to increase the CL or Lifting Force value/constant, I noticed in the F15 it has a script with a strength value.
A way like Plane Crazy and Kerbal space to visualize the Center of Lift as that will be useful for plane stability and dynamic workings or some lift force values at the least for each detected surface.
Make sure to check the collision decomposition for any holes and try have it on default or precise.
I had it on but noticed nothing unusual. My assumption however might be that it treats wings that are in many parts probably erratically. The A350 wing I have is in 5 main sections for the airfoil itself and then separate slats and flaps etc however from decomp it looked fine
Below is the collision decomp
The wing surface being split up could impact it, but idk. From my testing it seems that proper airfoil shapes generate more lift so you could give it a shot making sure your airfoil is properly modelled (which it probably is).
Anyways, in my case my plane didnt generate enough lift due to the conversions (specifically speed being too low) so heres a few of the core conversions that should be correct.
1m/s = 3.75 roblox studs per second (use this for speed ofc)
1kg = 0.045 roblox mass
oh yeah make sure every airfoil surface has proper weight and isnt set to massless.
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Cheers will try the weighting scale you suggested.
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The mass increases but so does the density of the air. Multiply the stock air density roblox provides by 21.952. I need to update my units conversion post with aerodynamics and doppler effect values but I have been busy with college lately. Because of this I have not had much time to test how well the aerodynamics system handles shapes other than singular blocks so it is possible with those numbers it may still not work.
Ironically enough the mass roblox calculates vs mine is off by a factor of 21.952. This means roblox switched their units for mass and density when calculating using the equation Mass = Volume * Density which threw off most of their other conversions. You can check out my post that lukethebestpug linked above for 2 proofs of the mass conversion. If you happen to find any mistakes in my calculations let me know I am open to constructive criticism.
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My day has been made, permanently.
This was buggy, difficult and slow to implement beforehand even outside of Roblox. Thank you for making this an engine-level feature we’re going to make good use of this 
Hmm I see this makes things tricky as the equivalent amount of Mass RMU wise for say an A standard twin jet heavy would put the Mass in the 100,000s RMU wise. Not that this means the calc is wrong.
Im ngl i highly doubt robloxs official calculations are wrong, and they work for my a330neo and other planes.
Id be more careful with trying to push your calculations as the right calculations since theres nothing to prove robloxs are wrong and yours are right.
Not just that i dont think you realize how insanely heavy 100k rmu is. You can barely have suspension hold up that much mass lol.
i hope you realize that 100000*21 is much heavier. the jets i’ve made have been around 200k, suspension is a matter of tuning proportionally.
you brought up that it’s 1/21 for 1 kg to rmu and called it “basic math” while quoting roblox’s page for saying 1kg is 28 rmu. that’s not how math works and that’s just an insult to me for you to think i’m that stupid to believe you.
i actually have an idea. take the weight of the f15 irl, then divide it by the f15 weight in game, and use the same strength values for your plane. take the quotient and then divide the irl weight of ur plane by it, and then use that as the mass. if it worked for the f15 it should work for you. based on that it’s just a matter of tuning the strength value. at this point there is no consistency for my translations, i’m using gravity on the realistic setting, so your best bet is just to try that i guess.
its the opposite way around, and yes its basic math, but you choose to be ignorant and spread literal misinformation.
The roblox docs state 1kg = 21.952 rmu, 1/21.952 = 0.045, the value in my post., you questioned how i got 0.045 since it wasnt explictly stated on the docs, and i explained that and called it basic math lmfao.
You came into my dms with a toxic tone trying to start an argument (which ive never talked or replied to you in this thread prior) claiming im spreading misinformation while the “misinformation” in question is off of the official docs.
Also i cant tell if youre purposefully changing the conversions ive stated in attempt to make what ive said seem wrong? either way im out of this convo man.
So for the bit in Blueish-Red you are not multiplying lets say 100,000KG by 21.952 as stated below to get its conversion in RMU. You’re dividing it.
For both Green and Red bits: Since KG is the bigger value and is 21.952 times bigger than the RMU value (as stated above by Roblox) then to find what 1 KG would equal to in RMU can only logically mean that you divide 1 KG by 21.952 KG which is about 0.04555 RMU.
This satisfies the logic because take
1RMU = 21.952KG (1 RMU To KG is a multiplication of 21.952)
1KG = 0.04555 RMU (1KG To RMU is a division of roughly 21.952)
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