Bug: Field Guns In Indirect Fire Mode: Shooting Into The Ground

[Vanir Ausf B]

To say the problem is a lower priority than other problems isn't ridiculing it. I've got pet issues I'd like fixed as well. At least you got BFC to post a reply to yours

[Battlefront.com]

Steve,

with that argument probably every problem can be ridiculed because there will always be an aspect, that is more important.

Who is ridiculing this problem? It's a real issue and it is one that should be addressed. And I am sure we will. I've said that over and over again.

And secondly, a potential solution to the problem, without the need to improve the AI, was presented, too.

I have seen no such proposal. Everything I've seen requires AI, even though you guys might not understand that.

Anything that happens without the user's direct action, and often even then too, requires AI programming of some sort or another.

The quickest way to fix this problem is the correct way. Have Charles "teach" the infantry gun crews to adjust the number of propellent charges being used based on conditions. It is more involved than AI to "pay attention to rounds as they impact and decide if the mission can't be adjusted and therefore cancel it", but I'd rather spend more time actually getting the guns to behave correctly instead of having a confusing feature that does nothing to get the rounds on target.

Steve

[Steiner14]

Drawing the trajectory of the weapon during setup phase requires the AI?

[Battlefront.com]

No, but that requires an entirely new feature that doesn't exist at all. Which means it would probably take LONGER to do than the AI work that would actually fix the problem.

Steve

[Redwolf]

The way I see it the right thing to do is for the FO to not FFE when no rounds are arriving at all. Doesn't sound too rocket scienty.

[womble]

The way I see it the right thing to do is for the FO to not FFE when no rounds are arriving at all. Doesn't sound too rocket scienty.

How does the FO know whether rounds aren't arriving "at all" if he can't see their splash? AIUI, IRL, what the FO does if they can't see a spotting round is request a "big" correction one way or the other until (within limits) they get a grip on which way "off" the shots are, and then they can bring it in, in a more directed manner. As I say, though, there are limits, and if the nth correction hasn't brought the spotting rounds into sight, the RL FO will cancel the mission. Again, AIUI, that's also what a fully patched CM spotter will do. Eventually. There was a time when if the spotter couldn't see the splash (say they were Hide-ing behind a wall and couldn't physically see the right locations any more), they'd just keep calling for spotting rounds, but I'm fairly sure that got changed.

[Georgie]

Who is ridiculing this problem? It's a real issue and it is one that should be addressed. And I am sure we will. I've said that over and over again.

I have seen no such proposal. Everything I've seen requires AI, even though you guys might not understand that.

Anything that happens without the user's direct action, and often even then too, requires AI programming of some sort or another.

The quickest way to fix this problem is the correct way. Have Charles "teach" the infantry gun crews to adjust the number of propellent charges being used based on conditions. It is more involved than AI to "pay attention to rounds as they impact and decide if the mission can't be adjusted and therefore cancel it", but I'd rather spend more time actually getting the guns to behave correctly instead of having a confusing feature that does nothing to get the rounds on target.

Steve

Wow, "teach the infantry gun crews to adjust the number of propellent charges being used based on conditions." Now thats shootin from the hip. OK, I'm convinced, no hurry, no problemo, I'll wait for that. Damn, I shudda thought of that.

[Redwolf]

How does the FO know whether rounds aren't arriving "at all" if he can't see their splash? AIUI, IRL, what the FO does if they can't see a spotting round is request a "big" correction one way or the other until (within limits) they get a grip on which way "off" the shots are, and then they can bring it in, in a more directed manner. As I say, though, there are limits, and if the nth correction hasn't brought the spotting rounds into sight, the RL FO will cancel the mission. Again, AIUI, that's also what a fully patched CM spotter will do. Eventually. There was a time when if the spotter couldn't see the splash (say they were Hide-ing behind a wall and couldn't physically see the right locations any more), they'd just keep calling for spotting rounds, but I'm fairly sure that got changed.

Firing artillery is so much easier when you don't care where the rounds go

I think the point stands, the problem is that a FFE is ordered without even observing any rounds hitting near target. That's not realistic.

[womble]

Firing artillery is so much easier when you don't care where the rounds go

I think the point stands, the problem is that a FFE is ordered without even observing any rounds hitting near target. That's not realistic.

Are you saying FFE was called without spotting rounds landing near the target? Because, AIUI, that would be a bug. As I said, I think it was meant to have changed so that FFE wouldn't be called if the observer couldn't get the rounds to be near. Perhaps it was only an intention that it be changed, or perhaps it was only mentioned as a possibility that it might be considered. I've never had the problem, even with really poor HQs in congested terrain. It might take a while for the spotting rounds to wander over into view and then into target, but they generally do. It's IGs that are going to have the problem most of the time because of their flat arc. Other times it's going to be because the player put his spotter team on Hide and forgot to unHide them once the spotting started. Ah yes. Found it in patch notes for 1.01:

http://www.battlefront.com/index.php?option=com_content&task=blogcategory&id=273&Itemid=459&limit=9&limitstart=18

When a forward observer cannot see where spotting rounds impact, he will usually require another round to be fired rather than skip ahead to fire-for-effect with poor accuracy.

If that's not happening, then there's something up.

Of course, if the FO can see the rounds hitting the treetops on the ridge the guns are trying to fire over, the AI hasn't got the brains to realise that the gunners can't just elevate another quarter turn of the knob and clear the obstacle, so will keep asking for another round. It may be that there's a limit for "Nope. Can't see it" recalls, but that the observer has no limit if they can actually see the "short" shots. Perhaps that could be addressed?

[Battlefront.com]

Of course, if the FO can see the rounds hitting the treetops on the ridge the guns are trying to fire over, the AI hasn't got the brains to realise that the gunners can't just elevate another quarter turn of the knob and clear the obstacle, so will keep asking for another round. It may be that there's a limit for "Nope. Can't see it" recalls, but that the observer has no limit if they can actually see the "short" shots. Perhaps that could be addressed?

I keep coming back to where things are going wrong and addressing the problem rather than the symptom.

The problem is infantry guns have multiple charges (IIRC 2 charges for the leIG 18). They select the number of charges based on the range they are firing. This changes the trajectory arc, which in turn allows for effective indirect fire over obstacles. CM currently doesn't have logic to handle this so they basically fire full charge even for short range targets. This works FINE for most situations, but it doesn't work when there is a significant height difference and/or significant vertical obstacle between shooter and target.

All problems that have been discussed here are a direct, repeat DIRECT, result of this problem. Code the AI to select the number of charges based on conditions and the problems, as stated here, disappear.

It's really as simple as that.

Steve

[womble]

I keep coming back to where things are going wrong and addressing the problem rather than the symptom.

The problem is infantry guns have multiple charges (IIRC 2 charges for the leIG 18). They select the number of charges based on the range they are firing. This changes the trajectory arc, which in turn allows for effective indirect fire over obstacles. CM currently doesn't have logic to handle this so they basically fire full charge even for short range targets. This works FINE for most situations, but it doesn't work when there is a significant height difference and/or significant vertical obstacle between shooter and target.

All problems that have been discussed here are a direct, repeat DIRECT, result of this problem. Code the AI to select the number of charges based on conditions and the problems, as stated here, disappear.

It's really as simple as that.

Steve

There will still be cases where high angle fire isn't possible. The Rmin for the IG18 on least charge at max elevation ("only" 73deg) has been estimated at 500m. Obviously it can fire shorter ranges than that at lower elevations, where the "trees on a ridgeline" thing could still banjax spotting. So it's still important to make sure that the spotter responds correctly to that kind of situation. Redwolf seems to be saying that the current spotter behaviour might need a look at in low angle fire cases.

[Redwolf]

I keep coming back to where things are going wrong and addressing the problem rather than the symptom.

The problem is infantry guns have multiple charges (IIRC 2 charges for the leIG 18). They select the number of charges based on the range they are firing. This changes the trajectory arc, which in turn allows for effective indirect fire over obstacles. CM currently doesn't have logic to handle this so they basically fire full charge even for short range targets. This works FINE for most situations, but it doesn't work when there is a significant height difference and/or significant vertical obstacle between shooter and target.

All problems that have been discussed here are a direct, repeat DIRECT, result of this problem. Code the AI to select the number of charges based on conditions and the problems, as stated here, disappear.

It's really as simple as that.

Steve

No, it's not.

There will always be cases where maximum elevation and minimum charge is not enough and then the unit needs to decide to cease firing.

The unrealistic thing is not that they hit the obstacle. The unrealistic thing is that they continue to waste ammo firing into it.

[Battlefront.com]

I don't disagree with you there. A FO who is told rounds are on the way and doesn't see them would definitely be inquisitive. So yes, I agree there should be a general behavior change. But I don't think it's that pressing an issue since we've never had that sort of behavior coded into the game and... what... 6 years later we're only now starting to talk about this. And only because of this one issue which, as I keep harping on, is based on the charge count and not FO error. Theoretical problem more than an actual one

Put another way, this thread probably wouldn't have been started if the charge count was chosen correctly. If the FO cancelled the mission the thread probably would have been started, though not for the same reason.

I've already reported both problems but together in one report. I'll make a separate report about FO canceling just to be sure it is understood the two aren't exactly inter linked.

Steve

[c3k]

Is the ability for high angle of fire (~73 degrees) taken into account?

[Battlefront.com]

With full charges that would probably land the round off map. That's the problem we face. The gunner has to aim nearly flat because that's the only option. Usually it works, too. But in Steiner14's case, it failed pretty solidly.

As I mentioned earlier, on map mortars *do* have the AI necessary to know how to adjust charges and angles to get the rounds to land where they want them to land. Unfortunately the inherent differences between a mortar (always arced trajectory) compared to an infantry gun (flat or moderate arced trajectory) means we can't just extend the mortar behavior "as is" to infantry guns.

Steve

[Redwolf]

Is the ability for high angle of fire (~73 degrees) taken into account?

You can't go into "mortar emulation mode" to fix this problem. It would look a little too ridiculous.

And I don't think that guns like the Flak 88, which could go to the required elevations, ever tried to shoot miles into the air to hit ground targets that were close but behind an obstacle. I think the accuracy after wind and aerodynamics from imperfect projectile shape would be so bad that it could come back right at the shooter.

The infantry guns can elevate very high but they cannot "play mortar".

[Battlefront.com]

I'm sure the high angle was designed to allow the IGs to hit the sides of steep hills or mountains. Just like the high angle of the Flak36 was designed to hit aircraft. The physics of the return trip to Earth would make it unlikely to land where expected even if one tried to use it like a mortar.

Steve

[agusto]

I'm sure the high angle was designed to allow the IGs to hit the sides of steep hills or mountains. Just like the high angle of the Flak36 was designed to hit aircraft. The physics of the return trip to Earth would make it unlikely to land where expected even if one tried to use it like a mortar.

Steve

According to the sources provided by *1, the leIG 18 7,5cm was used in direct and indirect fire:

"

Aus der Soldatenfibel des Jahres 1940:

„(1) Schießt man Flachfeuer?

Vorteil: Kürzere Flugzeit, geringere Streuung. Abpraller!

Nachteil: Infolge kleinen Auftreffwinkels wird ein Teil der Splitter im Boden verschluckt, ein Teil nach oben geschleudert.

Bei Steilfeuer verteilen sich Splitter besser dicht über den Boden.

Gegen Ziele in Bewegung nur im Flachfeuer schießen. Flachfeuer ist auch bei geringen Schussweiten aus allen Stellungen möglich."

freely translated:

"

Taken from the soldiers handbook of the year 1940:

(1) Engaging in direct fire?

Advantage: shorter flight time, less spread. Riccochets (from the ground)!

Disadvantage: Less fragmentation.

When used as indirect fire weapon, fragmentation covers a larger area.

Moving targets are only to be engaged in direct fire."

The v0 of a 75mm grenade fired from a leIG 18 was at about 210 m/s (690 ft/s), according to 2*. According to 3* this is the same muzzle velocity as of the M1 81mm mortar the US army used during ww2. So i think that physics would allow the leIG18 to be used as indirect fire weapon, similar to a mortar.

Here we have a photograph from showing the leIG18 beeing used as hgh angle indirect fire weapon:

1

http://www.lexikon-der-wehrmacht.de/Waffen/Infanteriegeschutze.htm

2

http://en.wikipedia.org/wiki/7.5_cm_leichtes_Infanteriegesch%C3%BCtz_18

3

http://en.wikipedia.org/wiki/M1_Mortar

EDIT: i tried to correct typos and grammar errors. But it s 4 in the morning over here, so i may not have suceeded in finding all of them.

[JonS]

http://en.wikipedia.org/wiki/Howitzer

... field howitzers introduced at the end of the 19th century could fire shells with high trajectories giving a steep angle of descent and, as a result, could strike targets that were protected by intervening obstacles.

[Michael Emrys]

Yes. I think Steve is trying to draw a too arbitrary distinction between mortars and howitzers. High angle fire by the latter would be useful in a variety of situations and I am confident was used by them on a regular basis, not only for clearing obstacles blocking LOS, but in direct fire mode against dug in troops. It's always nice to be able to mail a gift to opposing troops in deep trenches for instance.

Another fact that has so far been overlooked in this thread so far is that for the most part guns, howitzers, etc. achieve their maximum range at an elevation of more or less 45° (very large caliber or very high velocity weapons are an exception if they are able to take advantage of lower air density at higher altitudes). So aiming at a higher than 45° elevation actually has the effect of shortening the range of the weapon regardless of the propellant charge. Being able to alter both gives the gun crew considerable flexibility in bringing fire against targets in both direct and indirect fire.

Michael

[JonS]

No, there is a distinction between mortars and hows.

In terms of trajectory, from high to low, it is:

Mortars -> Hows -> Cannons

(with a lot of overlap between them all, and a few other terms - like 'gun' - arbitrarily in the mix too ... and no consistency within or between nations as to what is a gun, a cannon, or a howitzer )

[John Kettler]

agusto,

Nice work and a telling pic! Essentially, the leIG 18 (and the sIG 33) may be thought of as a slightly crippled mortar when firing at high elevation. It's slightly crippled in that it comes up about 10 degrees less max elevation than a Gw 34. Seems to me that a quick fix would be to apply a Rmin to the weapon when firing indirectly, just as on board mortars already have. The proposed fix could then be applied to all such similar weapons.

Regards,

John Kettler

[Michael Emrys]

No, there is a distinction between mortars and hows.

I know that very well, as you should have supposed. In fact there are several. What I am saying is that Steve is drawing a distinction that did not exist in reality and in practice.

Michael

[JonS]

I don't think so. He said that mortars could only conduct high angle missions (which is true) and distinguished that from Hows (and iGs, etc) which were able to conduct high angle, but could and usually would (in the specific case of the German guns, which are the only ones relevant to CM) conduct low angle direct fire missions.

[dieseltaylor]

I don't think so. He said that mortars could only conduct high angle missions (which is true) and distinguished that from Hows (and iGs, etc) which were able to conduct high angle, but could and usually would (in the specific case of the German guns, which are the only ones relevant to CM) conduct low angle direct fire missions.

I was unaware of this and had assumed the Italian Brixia and the 2" mortar could be fired flat aswell as high angle. Otherwise presumably they would have a minimum fire range.

It seems to me that there would be little harm and potentially a lot of good if BF actually made available the design constraints/fudges that the game enjoys. Knowing tanks do not have any problems with elevation/declination but other arms might is not a game breaker but it is irritating to find out through experience that a realistic WW2 tactic simply does not work as intended.

The same point regarding what is an expected set up time for an HMG in a house and why it is that way.

Waiting for players to discover what some already know seems to be more likely as an irritant than a realistic wartime learning moment. If you claim realism - as far as possible, then also be open about what is currently not possible or a fudge. Letting the world know that the game cannot reproduce the minimum firing howitzer range of an IG18 is no big deal but having reams of unnecessary discussion highlights the fact that other fudges/design considerations exist but may be unknown to the players.