SAAF JAS-39C Technical Data and Discussion

No M8 just do math lol. I don’t need convincing some one to facts. Or waste time to teach some one

So they may have equal drag when Mirage is faster and have better engine ?

LOL All right buddy, I’ll “Just do math”

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In game it does.

ω= (v/R)+(T/m⋅v) ⋅tan(ϕ)

ω is the angular velocity of the turn in degrees per second,

v is the velocity of the aircraft,

R is the radius of the turn,

T is the thrust of the engine,

m is the mass of the aircraft,

ϕ is the bank angle of the aircraft.

Ok just do the math tell me that thrust is not important…

Or it’s more convenient some Wikipedia equation from guy who don’t know what he talking about

@CorporalApollo are you good at math? huh? HUH?

I asked a real Gripen pilot how the Gripen stacks up against the F16 in a dogfight and he said they are pretty similar but that the Gripen regains its energy better/easier

It was a pretty generalized answer of course as he didnt go into detail with weight and all that but obviously he must have meant with similar loads/weights since it was a comparison after all.

I find that answer much better than results from exercises where there’s no context on how the battle was won like you emphasized (not to say Gripen has done badly in exercises)

are you inside jas39-dcs-mod discord by chance?

Sorry no I’m not

That doesn’t really give any actionable information and can also easily be chalked up to personal bias as well.

There are different ways that the anecdote can be true in a dogfight. For instance if Gripen has really strong initial turn into good position then F-16 pilot might end up bleeding all of their speed while defensive. Or it could simply mean that both rate about the same.

FWIW the guy that I know in the USAF says that Gripen is hard because it can pull omegalul AoA when it wants to. So maybe it should perform more like F-18 style flight model and less like F-16. But without actual sources who is to say?

My personal opinion from playing the Gripen in sim is that it is just a more capable F-16A with more flares and a better radar. There is nothing that anyone in something like a Mirage 2000 can do to me while I just dump flares all over the place. It is actually kind of boring and one-note.

True, I was mostly making a point that it’s roughly as good as a reference as those exercises we have zero context of.
I think it’s better looking at what real pilots are saying to get an understanding of the capabilities, instead of using single data points in sources and trying to “approximate” diagrams that way since most of it is classified

Yeah I was a bit sad when they didn’t model that for the Gripen in game, the instability of the M2K or Draken when you can get that kind of AOA. Instead they modeled it like a beefed up F16 at first?

Just turn on manual controls in F-16 and it can also pull up to like 40 AoA. It’s kind of weird that Gaijin has modeled it the way that it has but it’s only something that matters in sim and if the player knows what they are doing.

Yeah that’s a deal breaker for Gaijin lmao

I mean there is only like maybe a dozen or so people that play top tier sim and aren’t absolute amoebas.

The average Gripen player in sim is just carried by Aim-9M and having a billion flares.

Even starting behind me…this highly skilled sim player died to me almost instantly in spite of being in a better maneuvering plane.

Previously he was trash talking in chat about US players = bad, and from the looks of his stat card he primarily played F-16C in the last patch.

Sadly. Wish you prop people would play some more top tier lol. Last time I met you in sim was Netz vs Mig29 pre nerf
Btw I’m the Apollo guy in your discord

Please bookmark this thread and read what you’ve posted here again after you’ve graduated. I hope you see how foolish your posts here are.

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enlight us

Alright let’s do a quick sanity check (always good to do this for complex interactions)

The thought experiment

Let’s say we have a plane with some known TWR, which we will play with in this thought experiment.
We know this plane’s best sustained turn rate, at which point thrust = drag.

Increasing thrust

Now let’s increase the TWR of the aircraft by increasing thrust. This suddenly makes the thrust bigger than drag, causing the aircraft to speed up, going around the same circle[1] but faster, hence rate increases.

Decreasing weight

We could also increase TWR by reducing the weight of the aircraft, which we do by reducing its mass. This will increase the centripetal acceleration created by lift, hence the turn radius gets tighter. The drag produced stays the same, so we are going at the same speed around a smaller circle, so rate also increases.

Yes, TWR does not tell you the full picture, but it has a strong correlation to sustained turn rate.


[1] Turn radius is mostly independent of speed, as long as you’re reasonably faster than stall speed, and your control surfaces have no problem deflecting.


As for your comment on gliders, they do have a TWR 0, and they do not have a sustained turn speed, not without losing altitude. A glider cannot sustain a turn without also diving, so it is losing energy constantly. A horizontal sustained turn assumes constant altitude.

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but then again, why bother with TWR when you only need thrust?

Well, 80 comments later and the T/W argument continues. Gaijin modeled it to do ~20-21 deg/s on half fuel. The test I shared previously that was used to show it can’t do 20 deg/s was at 30 minutes fuel load.

Sustained turn rates are pretty much on par with F-16 currently.

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