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Old 12-27-17, 04:15 PM   #1
stratege1401
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Default Are we missing something with NX torpedo.

trying to mod the new F21 Artemis torpedo, I found this in the weapons.txt files (from captainX3 github project, btw thankssssss you so much):

Quote:
//These stats are for the F17 Mod2, in service date 1988-
//Data for earlier variants:
//F17 Mod 0, 1973, 19,700 yards / 35 knots; 31,700 yards if operated at 24 knots during wire guidance phase
//F17 Mod 1 (19??), range / speed of 22,000 yards (20,000 m) / 35 knots. Passive only.
//F17 Mod 2 (1988), range / speed of 22,000 yards (20,000 m) / 40 knots. Active(/passive?).
//F17P Mod 2 (1988), range / speed of 32,000 yards (30,000 m) / 35 knots.
//The DTCN F17 was a wire-guided anti-surface ship torpedo originally produced in 1971. France, Spain, and Saudi Arabia were its primary users.
WeaponObjectReference=fr_f17
WeaponSprite=hud/uk/f17_sprite.png
WeaponType=TORPEDO
//Warhead=250
//250kg HBX-3, 1.5x TNT
Warhead=375
the warhead TNT equivalent definition is set to 1.5 witch seem ok at first.

But looking deeper in IRL data from several sources, i start to wonder if this 1.5 ratio is accurate.

If we look at F21 artemis data, the warhead is around 200 Kgs. The F17Mod2 is around 250 Kgs. See the point here ! Next Gen torpedo, smaller warhead !!!

Looking deeper, the F17 is carrying a 250Kg HBX-3 non-shapped warehead.
The F21 is carrying a 200Kg special PBX-B22xx shapped warehead.

Now, looking even deeper, those explosive, TNT, HBX, PBX, even C4 or other type have a Detonation velocity data.

I found those detonation velocity:
TNT 6900m/s
HBX-3 6917m/s
PBXN-7 7700m/s
PBX-B22xx family is ranged from 5500 to 8300 m/s. 8290m/s is the typical missile warhead
my sources:
https://fr.wikipedia.org/wiki/Torpille_F21
https://fr.wikipedia.org/wiki/%C3%89quivalent_en_TNT
http://www.eurenco.com/wp-content/up...renco_2015.pdf
Cooper, Paul W., Explosives Engineering, New York, Wiley-VCH, 1996
https://en.wikipedia.org/wiki/Table_...ion_velocities


Adding to that the shapped form of the warehead !!!

Looking even deeper, i found those ratio of "explosive pressure equivalent" from 150% to 400% from TNT from an old study concerning first gen RDX explosive from the 80' ( p17-18 http://www.dtic.mil/dtic/tr/fulltext/u2/a115610.pdf )



So, now, going back to F17-250KB HBX-3 non-shapped versus F21-200 Kg PBX-B22 form shapped ... HOW do we translate accuratly this ??

Doing a mix of this

Quote:
WeaponObjectReference=usn_mk48_adcap
WeaponSprite=weapons/sprites/usn_mk48_sprite
WeaponType=TORPEDO
//Incorrect PSM value (this is the value in pounds not kg)
//Warhead=650
//292.5 kg of PBXN-103 = 544 kg of TNT - same warhead as standard Mk48
Warhead=550
.... and some extrapolation ??

I did not found the caracteristic of the mk48 warhead (it say high explosive only) but the mark46 say 98 lbs. of PBXN-1.03 high explosive (bulk charge)
https://fas.org/man/dod-101/sys/ship/weaps/mk-46.htm


I thing we should greatly modify the TNT ration for the MODERN WARHEAD like for the new mark48 Adcap Mod6-AT, the mark54L, or the F21 Artemis.


---
i corrected this post after finding data for the mark46 warhead. did not- found PBXN-1 data and used the PBXN-7
concerning the 1982 RDX studies, i beleive they were testing the PTX-2 mixture for his high brisance (41-44 % RDX, 26-28 % PETN et 28-33 % TNT) but the TORPEX ( ) mixture was even more reactive due to aluminium (42 % RDX, 40 % TNT, 18 % aluminum)
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Last edited by stratege1401; 12-27-17 at 04:39 PM.
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Old 12-27-17, 04:52 PM   #2
stratege1401
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Default

answering myself for connivance:

What about the RangeInYards for the torpedo ?

We are jumping from approx 22000 yards to 55000 !!!

Officialy, the URSS k-162 submarine is listed as the fasted submarine in the worlds ... the P21 is said to be fastest ( 10 kmh more ) ...

The P21 is quite a challenge to create !!!
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