Missile aerodynamics simulator

Dilbert

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Maybe this will be interesting for someone,

Some time ago I became finally so frustrated with meaningless comparisons of air-to-air missile ranges found on the web (and even in some books and journals), that I decided to program my own aerodynamic simulator for making own comparisons at different launch airspeeds, altitudes, etc. I don't have a solid confirmation that the results are accurate, but I've found it educational and somewhat useful for rough comparative purposes, and had some great discussions out of it on other forums:

http://www.ecf.utoronto.ca/~pavacic/missiles/minizap.zip
 
The specs (weight, dimensions etc.) have very little guesswork, around 90% is based on verifiable unclassified data.

The errors result from (a) trajectory model, since this is mostly guesswork especially for loft, and (b) drag coefficient, since no two references that I used seem to agree how best to calculate this exactly. :(

Although it probably won't give absolute range/speed accurately, I think it's still quite handy for comparison purposes, which missile flies farther/faster/higher than the other, since errors (a) and (b) should affect two compared models more or less the same.
 
nice ;) yesterday I was playing with that a little and compared various missiles with my sources. May I ask where did you get those numbers like propelant mass, specific impulse, burn time especially of those russian missiles if you said a 90% of it isn`t guess work? Just for comparing your simulation, here is a nomograph for calculation of maximal launch distance of R-13M.
Vs-speed of aircraft (km/h)
Vsbl-closure speed to the target(km/h)
D-launch distance (km)
Dmax-maximal launch distance, corrected (km)
H-altitude(km)
r13m.jpg
 
Very interesting, thanks! I'll study it.

Some data for Russian missiles came from modern Russian-language journals (there was a good series in M-Hobby in recent years), but the best was real technical manual data provided by Eastern European source.
 
Interesting chart.

Would I be correct to guess that R-13 can be used only in a tail-chase from the target's six o'clock position, and only when the shooter is flying 1000 km/h or faster?
 
The exact R-13M launch limits are following:
-usable outside clouds, in night and day and sun angle min. 30deg
-aircraft minimal speed 550km/h, M>=0,8 in altitude max. 17500m, max. M<1.8
-usable altitude 50-15000m
-missile launch zone in rear aspect, min. 0.9km, max. 15km
-at racurses: from 0/4 to 3/4
-aircraft engine regime: from idle to afterburner
-max.allow. g-load limit when launch: 3.7

No closure speed limitations at all. Therefore, I think the graph is only recounting some "optimalized" intercept speeds. If you draw parallel lines on the other side, e.g. -100km/h, -200km/h,....you`ll get shorter launch distance, and hit "zero" distance at some point.
 
"at racurses: from 0/4 to 3/4 "
Does that means that R-13M is capable of head on firring ?
Thanx
 
Dilbert said:
Maybe this will be interesting for someone,

Some time ago I became finally so frustrated with meaningless comparisons of air-to-air missile ranges found on the web (and even in some books and journals), that I decided to program my own aerodynamic simulator for making own comparisons at different launch airspeeds, altitudes, etc. I don't have a solid confirmation that the results are accurate, but I've found it educational and somewhat useful for rough comparative purposes, and had some great discussions out of it on other forums:

http://www.ecf.utoronto.ca/~pavacic/missiles/minizap.zip

You programmed a great tool. Actually I recently had a similar problem and was frustrated about useless data on maximum vertical speed and climb performance. I wrote myself a little simulator. Weakest point is the drag model in transonic region and drag penalty of external stors. Additionally all information on low-bypass engine behaviour of Mach and altitude are welcome.
I just downloaded the F-18 manual and will see if I can drive any conclusion about it's drag from it.
 
A interesting tool. But the missile data seems to be 'hard-wired' into the EXE file.

I can see how to get the program to write a datafile for the missile being simulated, but is there any way of getting the program to save and reload missile parameters devised by the user?
 
Hi, Excellent simulator, thanks for sharing.

I used to test ground-air missiles like the VT-1 (crotale ng) and 57e6e (Pantsir), and got the results published by the manufacturers but using skin drag factor of between 0.8 and 0.9.

vt-1: http://www.thalesgroup.com/Portfolio/Documents/VT1_brochure_pdf/

57e6e dart: 32 kg, 1300 m/s, 90mm diameter.
 
i can't get realistic figures for ground launched missiles, though. does the program simulate those, since it includes a template for patriot and s300?


I always get unrealistically high engagement ceilings as possible, even for short ranged missiles like aim-9 and such.


Also, i dont understand if the templates for various missiles already include a fear deal of manouvering through which quite a bit of energy is lost? Is there a way to simulate pure maximum ballistic trajectory (even if depressed) ranges for any given missile?
 

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