Game design question re mortars

[Dark_au]

This is not intended as an inflamatory post.

I would like to ask the rational of the firing angles of the Mortar carriers. I would have thought they would be more usefull / efficient in a semi-indirect mode firing in angles up to 45 degrees (for optimum distance to height). This would give them a much shorter flight time and allow them more chance to pierce AAD-PD in a coordinated attack.

Edit:- I can understand the rational of not wanting them to be used in a direct fire mode like the Hurricane, which I consider more of an assualt gun than artillery. However limiting the firing angle to say 15 - 45 degrees would achieve similar.

[ August 18, 2006, 07:37 PM: Message edited by: Dark_au ]

[cool breeze]

Good question. I have been supposing it is to shoot bigger without rolling, but I fully agree it should be an option. I hope it shoots up down to near 45, maybe only forward and backwards like 120mm apollo, and down to 45 with lower power shells in any way, plus delay fuse option. That is my dream mortar for drop team. Id love to try it anyway, soe if it is fun for all. 45 might look a little to steep for the model, I would like to see.

[ClaytoniousRex]

The mortars use high trajectory angles so they can be effective at truly indirect fire.

For any point that you want to hit with a ballistic trajectory (with a fixed velocity of the outgoing round) there are two solutions - a high trajectory and a low trajectory. 45 degrees is always the longest range. Raising or lowering the angle decreases the range.

Most weapons in DropTeam choose the low trajectory solution. Mortars are the exception. They choose the high trajectory solution in order to maximize the height of the projectile. This makes them useful for their primary role which is indirect fire, ideally out of LOS of the enemy. A mortar is best used behind steep hills, out of sight of the enemy, using the CTRL-M or targetting waypoints placed by team mates. With a high trajectory shot, the round will go over the maximum amount of intervening terrain (and other obstacles). With a low trajectory shot, you generally have to expose yourself to LOS of the target (though you can sometimes clear some *very* shallow terrain obstructions with a low velocity round, such as we all do now with the Hurricane from time to time).

You're quite right that there are times, even in a mortar carrier, that you would like to deliberately use a low trajectory shot instead of a high trajectory one. For example, when you ARE in LOS of the target (woops!). The ultimate solution would, of course, be to allow you to toggle between high and low so you can choose what fits your current needs the best. And as it happens this is pretty darned easy to do. We were within inches of doing it, as a matter of fact, and if there is now once again interest in this feature then it's a no-brainer to include in the next release.

[Dark_au]

My main interest was in the distance / time of flight equation.

With a quick bit of code doing ballistic math, based on 1G world and a 4kg shell at 400m/s at earth normal air density:-

75 degrees distance 8075m Time of Flight 78 seconds

45 degrees Dist 16,122m TOF 57 sec

15 degrees Dist 8114m TOF 21 sec

[cool breeze]

Have you ever had success wih the light mortar indirectly? I have so far used it exclusively for lLOS firing becasue of the small blast. is it sometimes effective ctrl-m? light mortar is almost the only mortar I use. I love making dust! I am very interested in any new mortar features you want to add!

[ClaytoniousRex]

Correct, low trajectory will give you less flight time, which is the main reason you would sometimes want it (if there are no intervening obstacles to need to clear).

(BTW, 4kg shell is irrelevant)

Cool breeze, the light mortar is very difficult to use indirectly due to its small blast area. It would really benefit from this new low trajectory toggle.

[Dark_au]

Roger, I realise that its a "plasma" mortar but it must have some mass / air resistance or why would it comedown at all.

[yurch]

Would be harder to get that top-shot with the low-angle, depending on how close you are.

Which brings me to a question: Would angle of impact really matter at all for an unshaped explosive? If I recall, the mortars in-game have a penetration that acts somewhat like a HEAT round...

[ClaytoniousRex]

Roger, I realise that its a "plasma" mortar but it must have some mass / air resistance or why would it comedown at all

I only meant that mass doesn't effect flight time. You would get the same flight time with a 4,000,000 kg shell at 400m/s. Neil Armstrong on the moon with his hammer and feather, ya know...

Would angle of impact really matter at all for an unshaped explosive?

No, but it would for the fragments which originate from it, and it those fragments penetrating the armor that we're modelling (not the concussion of the HE).

EDIT: Yurch, there's also the *direct* projectile hit which I guess is what you were talking about. You're right, it does try to penetrate like anything else but its penetration is extremely low. As to whether this is correct or not, I think so, since its penetration is correctly low. Angle would still definitely help against anything trying to push through armor.

[ August 18, 2006, 10:04 PM: Message edited by: ClaytoniousRex ]

[Dark_au]

Ahhhhhh ok yes... My mistake. I built it into a base I'd written for missile flight calculation where the mass does have an effect.

[Dark_au]

Wouldn't the concussion effect crew stunning, delicate instruments / gyros etc with the shockwave?. How about a temporary dammage like emp (with say a 2-3 second fix per item) to portray the "fuse bank" popping?.

[ August 18, 2006, 10:09 PM: Message edited by: Dark_au ]

[ClaytoniousRex]

Wouldn't the concussion effect crew stunning, delicate instruments / gyros etc with the shockwave?.

Definitely, and this kind of "shock" is one of the things that adz and bjarmson pointed out that we should be doing but currently aren't.

[yurch]

Originally posted by ClaytoniousRex:

No, but it would for the fragments which originate from it, and it those fragments penetrating the armor that we're modelling (not the concussion of the HE).

Right - but our mortars have higher penetrations than the shrapnel. A square hit with the hurricane to the side of say an Apollo will penetrate (xxx was killed by plasma mortar) whereas a glancing hit to the side kills by shrapnel (xxx was killed by artillery).

Hurricane mortar has a whopping 275 penetration for this effect.

I guess that would mean the big fat slow shell is actually penetrating the armor before detonating, but that sounds pretty crazy to me.

Edit: I really need to hit thread refresh.

[Dark_au]

actually my math was suspect in those numbers. Thought it was a bit high, I'm mis-named my drag coefficient and it was not bieng included