Anyone can compare gaijin loft r-77 and with disable loft?
Su-47 was a marketing stunt by Sukhoi, not a genuine prospective fighter. MiG’s MFI program was the Soviet’s choice, when the USSR collapsed Sukhoi Sukhoi used the Su-47 to throw up a smokescreen to make it appear as if MFI had competition worth considering by and make it less likely that the Russian Federation would put any real weight behind finishing up the MFI before Sukhoi had their PAK-FA proposal ready enough to bullshit the government into going with Sukhoi’s newest shitpost. Similar story to Object 195 being cancelled in favor of T-14.
No, you are just ignoring it because it doesn’t align what you assume to believe what is correct despite conceptual proof and data proof. Go ahead, tell me the dimensions then. To the detail. Gap, chord, length, height of the main fin.
I’m not covering anything. The document was posted for all to see.
You don’t understand all do you? You are doing some mental gymnastics here.
Again, the grid fin has a much much lower hinge moment. Meaning swervos need to do less force required to attain a certain AoA.
This has NOTHING to do with the lift/drag ratio as a function of cl. You are doing some high top tier level mental gymanstics by trying to find a link between these two, and then claiming they are wrong.
I told them, above Mach 4-5 for lower drag, higher lift (existing cl as high as 40-50 as a planar fins just don’t generate lift at these angles) at high AoA, lower hinge moment in all domains.
Nah nah nah nah. Don’t take it out of context(0° AoA), you saw how at 0° its 5x then as AoA increases, the Cd numerical difference is roughly the same. With grid fins having higher AoA at all angles at M2.5.
Just a simple critical thinking will show you otherwise, what has more frontal surface area perpenducular to the airflow? 1 planar or 8 planar fins witg the same size?
Of all papers regarding grid fins, planar fins, or both, 1 single fin has a lower Cd that grid fins is roughly the same by order of magnitude
Of course you are. “Less drag below Mach 1.3”. Based on what? No values given etc. Just a plain random number which as you saw above depends on lots of thing. But of well, I mentioned why it was baseless but looks like understanding of what its a function of is ahead of you.
AND I’M STILL WAITING FOR A RESPONSE FOR THIS!
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Again, the grid fin doesn’t require equal AoA to planar for similar torquing moments on the missile.
If you’d stop pretending to misunderstand torque moment provided by the fins vs torque required from the servo it would.
No, you’re misleading. You already admitted you don’t understand how the grid fins improve accuracy and maneuvering performance at lower airspeeds and higher AoA.
You’re implying the planar fin has anywhere near the same torquing moment on the missile as the grid fin without having nearly equal drag is… interesting. The grid fin not only enhanced maneuverability with reduced size but allows for higher AoA, stability, accuracy, and less drag than the larger planar fin required to do not quite the same job.
… What?
How is it baseless, it’s data already discussed and provided in sources in this same thread.
It’s not relevant, I’ve pointed out how the response given is purposefully misleading. You realize that I’m not the one you must convince to a-historically nerf the missile right?
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How is it inaccurate to real-life?
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In real life rockets ramp up to correct thrust and then it ramps down as propellant goes empty. In-game it is an on/off switch and is often adjusted to ensure correct overall energy and time to target is met. As such, values change from that which was historical. Additionally, during motor burn missiles have less drag thanks to the aerodynamic cone of thrust behind them. To account for the reduction in drag they may simply raise thrust slightly since the drag value is static.
Overall, specific impulse may not match but deltaV should be similar.
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I see, their power output is reminiscent of that of battery-powered things? That’s the best comparison I can think of to begin understanding this
How drastic of a difference would the thrust output make?
Yes, these are both well-known issues with Gaijin’s modeling that they hack in order to compensate for. The point is that their initial pass at stats gives the missiles similar Isp so I do not expect them to significantly change their relative performance.
Right, the graphs show that very clearly.
The graphs Chartreuse is sighting give torque moment on the fin hinges/servos, not torque moment provided by the fins. Torque moment provided by the fins is a function of the Cl, and drag from providing that the Cl/Cd graphs. And the graphs clearly show that the grid fin provides more lift/missile torque at the same AoA, but more drag until a commanded Cl of 0.6-0.8 depending on mach, corresponding to 12-20 degrees fin AoA.
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No, specific impulse measures the efficiency of the motor and propellant. It is a measure of how much thrust over time is produced based on the amount of propellant burnt. More thrust over more time with less propellant used is higher efficiency.
Currently AIM-120 and R-77 appear to be underperforming. Both match historical thrust figures, as such should probably get a ~15% improvement in thrust to account for reduction in drag during burn time. Additionally, the lofting is not very efficient and shouldn’t exist on the R-77. The R-77 should have similar current range but without lofting so it needs to be adjusted in drag as well.
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What are the conditions for lines 1, 2, and 3? I presume that Kmax is L/D dimensionless and M is mach?
Kmax=Сlopt/Cdmin
M=Mach
- The frame structure of the Grid Fins
2.Cellular construction of the Grid Fins - Conventional monoplane wing
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Kmax is pretty much a useless figure then. Because it’s comparing maximum lift to minimum drag.
Well, if it’s a useless value for you. Then I have some bad news for you.Your knowledge of aerodynamics is zero
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Ah, I misread then. I assumed the “ramps down as propellant goes empty” to mean the output of the motor itself in relation to its remaining fuel.
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That actually depends on the grain pattern of the propellant. It can fizzle out or ramp up in thrust in the final moments.
I know exactly what it means lol but it is just very useless outside a limited sort of optimization problem where you want the maximum provided moment for the minimum cruise drag. But in reality missiles ofc actually care about their L/D through flight, and their absolute not relative Cd. If the fin provides lots of moment but high drag when it does this Kmax figure completely hides that, and similarly it hides if the missile provides higher moment but at the cost of higher drag.
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Any aerodynamicist looking at this graph will tell you how well this or that aircraft flies. The graph shows how aerodynamically perfect it is. The torque generated by the lattice steering wheel is required less than by the monoplane
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You’re soooo unbiased tossing around “aerodynamically perfect.” Also actually I shouldn’t have trusted your explanation, because it’s wrong. Kmax isn’t Clmax/Cdmin. It’s the maximum value of Cl/Cd for any AoA, the optimal lift coefficient. Which makes it more of a useful number(if you’re designing a bomber or something), but not the applicable number for a missile because the missile can’t choose an AoA to fly at to maintain its trajectory to minimize Cd, it must maintain a fixed amount of lift which means a varying Cl as it’s speed changes. So this single number isn’t what needs to be optimized.
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If you think I’m wrong, you should be able to explain it. Memeing = admitting defeat.
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