Issues with the JAS 39 Gripen flight model

I stand corrected, though it seems mass can only be viewed through the flight model test page and not localhost proper?

It’s not total mass but you can see fuel mass

The localhost fm commands page can be used to get total aircraft weight for a certain fuel percentage. The way of getting it is kind of convoluted because the fuel percent commands are based on with drop tanks…so you have to figure out what percentage of total fuel is 50% internal fuel etc.

The way to short cut this is to just load in with 50% internal on fuel slider…look at the time…and then adjust the percentage in localhost command until it matches the 50% internal time.

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I know, but from normal local host you can only see the fuel mass

He just explained how to get total aircraft weight from localhost. It’s convoluted, but the information is present.

I know, I was just saying that in local host proper you can’t see the total mass (as feet explained you can only see it though fm commands), but can still see your fuel mass, since @Godvana was talking about localhost proper

The reason the Gripen over-performs is because the drag value is extremely low for the AoA.

F-16A Blk 10 experiences drag value of just below .6 at 25 degrees AoA.

Gripen experiences drag value of .3 - <.4 in its entire flight envelope.

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And how does that mean it over performs

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Cool charts. A representation of already known values but better than ‘max-pull’, assuming wing coeff is in direct relation to SEP it paints a clearer picture. Doesn’t provide any insight on where the Gripen should be though.
Question is what is it’s relation to the already correct STR (aside from the 1.3-1.7°/0.5-0.7° pointed out by Gio/devs), and what is it’s relation to SEP… Or is this disparity just a result of instability not being modelled

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The drag number of the Gripen at its AoA limit is basically half that of any plane in the game.

Theoretically the AoA limit could be increased to 35 degrees before the Gripen reaches similar drag values to the F-16 flight model.

Of course this is probably how you get the mythical 18G Gripen that was on the Dev Server.

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Curious to see what devs make of it with the update Gunjob gave

Where is M2K on that chart btw, just curious how it compares to the three, if the curve itself resembles one or the other

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Hello, can you make such graphs for the MiG-29, Su-27 and F-15

I already have graphs for 29 and 27.

Don’t have 15.

I can get it.

Can you share?

did the gripen just get nerfed because it’s way better than the viggen?

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What difference does this make? Is it significant?

turn slightly worse

Basically

i think this is their way of trying to emulate the lower AoA needed for specific lift at a specific radius.
And they have probably in the process miscalculated somewhere.

TLDR:
when it turns it does not loose speed as fast as it should, some argue it should be at the same level as F-16 or M2K. personally i think it should be at about 30% better. before todays change it was 100% better, no clue about the current numbers.

Mirage 2000 has good low efficiency and then experiences massive drag penalty near its AoA limit. If you do max performance turn in Mirage 2000 you will lose speed at high rate.

New changes to Gripen do not alter drag factor in any noticeable way.

Gaijin’s aerodynamics are very strange.On the contrary, at 0.8M there should be the greatest lifting force