The R-77 'ADDER' - History, Design, Performance & Discussion

[noister]

Base R-77 Have these “protrusions” at the base of the fins

R-77-1 Have less of these protrusions

Problem with finding out the drag is that you would have to find the width of the grid fins each lattice. They form wedge with small angles, that would have to be modelled too, which is pretty hard to do from just images, but they indeed taper, which you mislooked, it may effect the simulation significantly

Other than this, it would be better to have it as comparision to aim120a/b and c5.

Also, the missile rail is not modelled

[f15j_anmeagle]

@noister

you would have to find the width of the grid fins each lattice.

the geometry for the R-77 fins is known: 200mm long for 100 wide and 35mm thick with .75mm thick sheets (that is as modelled)

@noister

wedge with small angles

can easily change that so they are more streamlined than just blunt

@noister

Also, the missile rail is not modelled

yeah, i don’t got the skills for that, that’s why the fin mounts are different too

[noister]

@f15j_anmeagle

.75mm thick sheets

nice, have them tapered tho, like wedge

[f15j_anmeagle]

they don’t taper, it’s just the orthographic view (perpetual 2d) that can throw off a little if you’re not used to it (i’m still getting used to it)

one big issue i don’t know is wether or not the leading edge of the lattice is blunt like this or not

Spoiler

(edit: are we talking about the same thing in different ways? : | )

[noister]

by tapered i meant they are sharp, like wedge, not blunt

[f15j_anmeagle]

aye, my bad, i’ll edit it!

[noister]

also as i said before, better make a amraam model as comparision, as the simulation may not give the real IRL values at it might not be calibrated to it, however with results for both missile, we can relatively compare if in game values are accurate or not

amraam should be easier to model

( i suck at modelling, cant make shit, only remember making a nice modular swingy thingy which took me days )

[f15j_anmeagle]

if you can dm me amraam geometry i’ll make a comparaison yes (providing someone is willing to help me with CFD or my ansys stops being iffy)

[noister]

ill look up on it

[ron_23]

[f15j_anmeagle]

new fins, thx for pointing it out

Spoiler

[f15j_anmeagle]

[ron_23]

thats why i sent them

btw credit goes to the Codename Flanker Discord / @BBCRF

[f15j_anmeagle]

i know exactly what messages you mean XD

anyway, back on topic

[noister]

model scalable, 178mm is width of the main body of the missile, would have to use pixel mapping to find rest

[noister]

on basis on known width, i pixel mapped and found out the distances, note there will be around ± 5 to ±10mm of innacuracy, you would have to round off some values while making the model.

measurements in milimeters.

( i just noticed, dimensions were given in format of inches already… )

[kizvy]

Can u explain what im looking at

[noister]

same question

[ron_23]

aerodynamic simulations of a slice of the r-77 gridfins, at different speeds
@noister

[noister]

i really dont know what i can make out of it for in game purposes