Monday, January 9, 2012

Tigers Unleashed (HPS Simulations) - Gameplay Notes - What Killed Sonderkraftfahrzeug 251? The Blog Goes Into Battlefield Forensics!

In my latest entry, one of my German halftracks (SdKfz 251) was dispatched by an enemy 7.62 mm SMG firing from a wooded hill.

Bug? Oddball?

7.62 mm PPD SMG vs. German halftrack. Plot of detection time vs. distance in the sandbox mode.
Tigers Unleashed has a so-called "sandbox" mode in which the user can choose a firing unit and a target. The sandbox mode then shows the data for shots being fired from the firing unit and taking into consideration the distance, terrain, illumination, shadowing, even the angle of both units.

The accuracy of the Russian SMG at 188 m (yellow line, this is the distance between the firing unit and the target) is pretty decent. One can expect the German halftrack being hit with every other round of the Russian SMG.

The probability of kill is less than 1%. Note how the most exposed to fire area of the halftrack is the hull's top (46% of the total target area). This is because the firing unit is at a height of 10 meters and the target is at a height of 5 meters (see left info panel).
The damage probability is abysmally low. This is likely due to the low penetration of the 7.62 mm round into the armor of the halftrack.
The sandbox mode can also display the penetration data. In this case, showing the penetration of the 7.62 mm round into the armor of the halftrack which in the simulation is solid steel. Note how you can even plot graphs of penetration vs range for angled armor (here displayed at angle 0, because I'm just lazy).
The armor data for the target halftrack shows non-penetrable steel at all sides of the vehicle, except off course on the top, where there is no armor.
Taken altogether the data presented above allows me to conclude that I can't conclude nothing. :)

Seriously speaking, given the lack of penetration of the 7.62 mm round on the armor of the halftrack, the kill of the halftrack could have actually been a kill of the crew by rounds that entered through the top of the vehicle. This is something that BilH suggested in a comment to the original blog entry. However, the kill probability when a round hits the top of the vehicle is the same than the kill probability of one that hits the side of the vehicle. This is a bit odd.

I'm running the combat simulation with the combat resolution screen set to very low detail so to speed up the process. Now I am wondering that if I would have been more patient, the details of the kill would have been presented in such screen.



Anonymous said...

it seems that projectile mass and projectile length are incorrect
bullets of the 7.62x25 TT cartridges were 4,75-5,60g, not 9g
length is between 13,8-16,9mm depending on the cartridge
oh and there were 7.62x25 AP-I ammunition. it was available 41-44 in case someone reads russian

Anonymous said...

aaand i am aware of the fact that 7.62x25 AP-I probably would not penetrate 8mm solid steel at whatever distance your halftrack was destroyed.
just in case)

Dimitris said...

Impressive attention to detail.

grenvill said...

so much WHAT in this pictures:
smg accuracy droppping at close ranges and falling from 70% to 20% in 15m distance;
chance to kill same for hull top,front and side hits.
Also while gunner kill is possible( although very improbable at 100+m distance), you can never ever kill driver with small arms fire

Leontes said...

Absolutely nobody here seems to be fired ww2 era ammo against armour plates or even know basics of phisics....Despite an exceptional game routine a fundamental error was made (just like in almost all other games): no penetration of armour plate from ball ammo ! I was pretty lucky to fired an ball ammo ww2 era of a romanian ZB rifle and from 100 meters it penetrate 7 mm RHA of 250 BHN !!!!
Point !!!

Just go to
and that precise teoretically confirm my practice. When a patch to depict that ?