Observations on hull down

[Joeri]

Hi Guys,

This is my first post so I would like to say hello to everyone first. I received CM a couple of weeks ago and I have been playing ever since. What a great game!

Anyway while playing I noticed something I think was a little odd. It seemed that every time I was targeting something from a hull down position the target was also in hull down position. At least the hull down text appeared above the target. I thought at first this was a coincidence but after some more playing it seemed to me that always both the target as the attacker are hull down (or both not ofcourse) even if the target is clearly not hull down. So I decided to do some testing. I like to share the results of these test with you.

What I did was make a scenario with a small elevation on one side and totally flat for the rest (see pictures). On one side I put three Sherman Jumbo's (with 75mm gun) in hull down position. On the other side I put 3 Tiger's (with the slow 88mm gun). I chose these tanks to maximize survivability. I let them shoot at each other for some turns and register the hits (including position of hit). Next I put the Jumbo's in front of the elevation as to be sure that there was no hull down and again let them shoot at each other.

First off all let me mention that during the test with the Jumbo's in hull down. The target tool gave a hull down position for bot the target as the attacker. The attacker was indeed hull down behind the elevation but the target was not. In fact I had LOS at the area directly in front of the Tiger so it couldn't be hull down. This was the same effect that I noticed in the games why I did the test in the first place.

Let me try to post a picture of the situation. (hope this works)

Hope this clears up the situation.

The results of the test were as follows:

NS: -Number of shots fired

LH: -%Lower Hull hits (or track)

UH: -%Upper hull hits

T: -%Turrent hits (or gun hits)

H: -%Total Hit

For the Jumbo's in hull down position (distance 550m to Tigers):

------------- NS -- LH -- UH --- T ---- H

Tig. vs Jum.: 53 -- 0% -- 15% -- 45% -- 60%

Jum. vs Tig.: 81 -- 1% -- 23% -- 56% -- 80%

For the Jumbo's not hull down (distance 500m to Tigers):

------------- NS -- LH --- UH --- T ---- H

Tig. vs Jum.: 45 -- 18% -- 38% -- 29% -- 68%

Jum. vs Tig.: 40 -- 22% -- 35% -- 30% -- 87%

I can think of only two possible explanations for these figures:

1 - I totally don't understand the concept of hull down

2 - CM can only model either both target and attacker hull down or both not. In the manual (p.40 and 66-67) it says that hull down is calculated seperatly for target and attacker. So there is something wrong.

Any comments (please be gentle )

Joeri

[This message has been edited by Joeri (edited 08-31-2000).]

[Noba]

Borg ?

[Olle Petersson]

I haven't noticed that before, but my experience seems even more strange;

When my tank is on top of a hill and looks down at an enemy it's far more common for the enemy to be hull down than it is for my tank!

I think it should be easier for my tank to hide behind the curvature than for the enemy, upon whose roof I'm looking...

Cheers

Olle

[aka_tom_w]

Great post for a new guy

you might be interested to check out the gunnery range thread as well.

Very interesting theory re:hulldonwn either both or none. I had not noticed really.

I have to wonder if a target is hulldown how can you get a hit on the Lower hull?

Is that what you are reporting? In your test did the hull down target take hits to the lower hull?

Very curious?

Thanks

-tom w

[Tanaka]

<BLOCKQUOTE>quote:</font><HR>Originally posted by Olle Petersson:

When my tank is on top of a hill and looks down at an enemy it's far more common for the enemy to be hull down than it is for my tank!

I think it should be easier for my tank to hide behind the curvature than for the enemy, upon whose roof I'm looking...

<HR></BLOCKQUOTE>

No... lets be correct at this... If you are on the top ,( realy on the top of the hill), your hull is exposed. If you are a little behind of the hill top you could be in hull down situation.

João

[KiwiJoe]

Hmmm does seem strange. Though I've had a Jumbo shooting at a hull down panther for 3 turns. All my shots hit his turrent, as u would expect, his shots hit my lower hull once or twice and then an even(ish) number between upper hull and turrent. So that would suggest it does model hull down to only 1 unit.

[Jarmo]

Just a while ago one bloody critture took out my hull down panther

with a hit to upper hull. I don't remember being hit in lower hull

while hull down, but then I don't remember every hit my tanks have got.

I've seen situations where only one tank is hull down, but those

are kinda rare. Maybe too much so. And I've seen situations where

you can target the ground right in front of the other tank,

but the tank is still hull down.

I've also been able to target a foxhole, but not the gun in it,

so there's something fishy about the way targeting's being

done. Nothing very serious, though. Most of the time everything

works "right".

------------------

Now, would this brilliant plan involve us climbing out of

our trenches and walking slowly towards the enemy sir?

[Olle Petersson]

<BLOCKQUOTE>quote:</font><HR>Originally posted by Tanaka:

... If you are on the top ,( realy on the top of the hill), your hull is exposed.<HR></BLOCKQUOTE>

Perhaps I wasn't clear enough. I meant on a plateau, some way in from the (steep) edge. This should produce the same (hull down) result as being on a backslope.

Cheers

Olle

[Melloj]

I know this is a basic question in a more advanced thread, but the hull down label will only appear when the vehicle you are targeting or drawing LOS to has you in a hull down view, correct?

The reason I am asking is that I can't seem to get this to show, even when I am reasonably sure that I am Hull down. Does one have to have Warning labels on?

Thanks

[spcwrnglr]

Could it be that the Tiger tank is, in a sense, elevated in this case? The Sherman looks like its shooting up at the Tiger, maybe in this case, the ridge is an advantage to both sides.

I would be intereseted to see what would happen if the shermans were on a ridge ABOVE said Tigers.

[PzKpfw 1]

That is to say the least some very interesting results.....

Regards, John Waters

------------------

Make way evil, I'm armed to the teeth and packing a hamster!

[Joeri]

Some additional remarks on my post.

I hope it is clear from the pictures and the discription that the tigers are not hull down. However when targeting them (or with them) the hull down marker appears on both the Tiger and the Jumbo. This is not correct (IMHO).

I did the test to make sure that in the firing the hull down the Tigers where really treated as hull down (as the marker says). I think the testdata confirms this. Judging from the hit percentages on tuurent and hull, the Tiger is treated as hull down.

Since I have seen similar occurences in actual games (Including the one we are playing by the way Jarmo ). The treatment off hull down in this way eliminates the direct advantage you have from being in a hull down position, namely a decreased chance of hit (especially to the hull) compared to your target.

By the way, the Jumbo's and Tigers are chosen because they have a lot off armor so they live longer in the test. I have observed this effect for many other combinations in real games.

I also tested with various degrees of hull down. As you can see in the figure the shermans are not all in the same place behind the elevation. I run this test two times with even more different positions.

To Melloj:

You get the hull down marker when you target a verhicle. The marker can be both on the target and/or on the attacker (according to the manual). In my observation the marker is always on both or on nobody.

Joeri

[This message has been edited by Joeri (edited 08-31-2000).]

[chaos]

I wonder if it has something to do with the maximum depression of the Sherman's gun? In this case, perhaps the Tigers are hull down (in a sense) because the depression of the Sherman's gun only allows for a turret/top hull hit.

cheers

chaos

[Jarmo]

<BLOCKQUOTE>quote:</font><HR>Originally posted by chaos:

I wonder if it has something to do with the maximum depression of the Sherman's gun?<HR></BLOCKQUOTE>

Maximum depression/elevation is not modelled.

------------------

Now, would this brilliant plan involve us climbing out of

our trenches and walking slowly towards the enemy sir?

[Aloid]

I remember the manual being a little confusing on how it tells you that YOU are hull down. It seemed like the manual was saying that the "Hull down" description for your tank was displayed when you had the cursor over your target.

Perhaps I'm remembering it incorrectly... (Drat! I knew I should have brought my manual to work! - well, then I really wouldn't get anything done, heh!)

The results from the test look correct to me, especially if the Tigers are slightly below the Shermans. Also remember that shell trajectories are not straight lines,so I'd think it possible on some shots, to hop the slope of the hill a little, and hit something below the turret.

Aloid

[Doug Beman]

IIRC, the manual says something about the hulldown labels appearing above or below the label of the vehicle. If the hulldown appears above the vehicle's label, that vehicle is hulldown. If below, the vehicle is being targeted by a vehicle that is hulldown.

Or am I mistaken?

DjB

[Magnus]

<BLOCKQUOTE>quote:</font><HR>I also tested with various degrees of hull down<HR></BLOCKQUOTE>

Unfortunately, various degrees of hull-down are not modelled in CM, so you don't need to worry about that for your tests.

------------------

Venez visiter le seul site consacré à Combat Mission en français : Appui-feu http://appui-feu.panzershark.com

[Spacewrangler]

Alright, I took this post pretty seriously and really paid attention in my moves tonight for my PBEM.

I'm on a Mac running V1.05.

The manual DOES state that if YOU are hull down, it will display "hull down" underneath your tank. If your TARGET is hull down, it will display hull down under the TARGET.

Well, just now I had a flanking shot, from higher elevation, on an IMMOBILE Panzer from about 300 yards with a Jackson Tank Destroyer. Yes, he has 90 degrees to me, just sitting duck. As I said, I had elevation, had "hull down" beneath my tank, but so did he.

Now this can't be right. My line of fire was perpendicular to his, there is no way he could have been considered hull down in any circumstances. This did not prevent me from knocking him the f*** out with a single shot (it said kill:excellent) so I'm not complaining. However, it was a "side upper hull penetration." I don't know if that's where my gunner was aiming, or if he just missed the lower hull, but that's the way it worked out.

Bottom line: it seems the hull down calculations may need some tweaking, I don't think there's ever a time the attacking tank can have hull down on a non-hull down armored unit.

[L.Tankersley]

I am virtually certain I have seen non-reciprocal hull-down situations. I'll keep an eye out to provide documentary evidence. My memory indicates that it is often reciprocal, however.

<BLOCKQUOTE>quote:</font><HR>Well, just now I had a flanking shot, from higher elevation, on an IMMOBILE Panzer from about 300 yards with a Jackson Tank Destroyer. Yes, he has 90 degrees to me, just sitting duck. As I said, I had elevation, had "hull down" beneath my tank, but so did he.

Now this can't be right. My line of fire was perpendicular to his, there is no way he could have been considered hull down in any circumstances.<HR></BLOCKQUOTE>

This is incorrect. You need not be facing the firer to have hull-down status w.r.t. that firer. Hull-down means the firer cannot see the lower portion of your vehicle for whatever reason. Target facing has nothing to do with it. It is also possible to be hull-down while lower than the firer. All you need is some low rise or other obstacle between you and the firer. It could be a wall you're sitting next to, or a low rise (maybe only one elevation level change) - it doesn't take much elevation change to obstruct LOS to the bottom of your vehicle if the firer is some distance away. You might try setting vehicle size to realistic, locking view 1 to the firer and use the zoom keys to zoom in as close as possible on the target, and carefully inspect the bottom of the vehicle to see if you're truly seeing all of it. Remember also that even view 1 is situated a bit above and behind a vehicle, so if LOS is borderline from this view it could be blocked from the gun mount. [Let me here repeat my request for a true TC-view in future.]

------------------

Leland J. Tankersley

[Lorak]

question....

If you were well above your target wouldn't they by default be hull-down? Granted your kill % would be higher (firing at an angle towards more top armor) but their hull would be harder to hit.

Lorak

------------------

Proud commander of the CCT's Chinchilla Commando Teams

[Cueball]

I ran a test to see if I could create a non-reciprocating hull down scenario.

It turned out to be quite easy. I created a flat map and put one unit behind a wall.

[Juardis]

<BLOCKQUOTE>quote:</font><HR>Originally posted by Joeri:

Hi Guys,

For the Jumbo's in hull down position (distance 550m to Tigers):

------------- NS -- LH -- UH --- T ---- H

Tig. vs Jum.: 53 -- 0% -- 15% -- 45% -- 60%

Jum. vs Tig.: 81 -- 1% -- 23% -- 56% -- 80%

For the Jumbo's not hull down (distance 500m to Tigers):

------------- NS -- LH --- UH --- T ---- H

Tig. vs Jum.: 45 -- 18% -- 38% -- 29% -- 68%

Jum. vs Tig.: 40 -- 22% -- 35% -- 30% -- 87%

<HR></BLOCKQUOTE>

Can't answer the hull down thing, but it appears that the game is incorrect.

What I'm more concerned about is the accuracy of the Tiger vs. the Jumbo. I mean the Jumbo is 20% more accurate than the Tiger? At 550m, with neither tank moving, both crews of same quality, I'd expect about the same accuracy from both tanks. Were both crews of the same quality? Were both tanks stationary? If yes to both questions, then is this the gyro-stabilizer tipping the scales in the jumbo's favor? That's the only thing I can think of, but even then, if neither tank is moving I can't see how that should matter. Most peculiar.

------------------

Jeff Abbott

[Guest Big Time Software]

I made a fix to the LOS algorithms in one of the patches and might have introduced a bug with regards to the hull-down status. I'll check into it.

Charles

[MichaelU]

Nicely spotted Joeri, and a nicely laid out post. I'd think I've also seen this behaviour, and if it is a bug I'd like to take this opportunity to thank Charles because I'm useless at getting my tanks into hull down positions whereas my PBEM opponents are not.

[Joeri]

Cueball,

Ok, so walls work. It would be interesting if someone could find a situation wit non-reciprocating hull down by using elevations. If anyone has an example I would be very interesting in recieving a file or picture.

Juardis,

I also was a bit surprised at the percentages especially the small difference in total hit chance between hull down and not hull down (68%-60% for tiger and 87%-80% for Jumbo). I think this might be due to the following. In the hull down scenario, the tanks fired at each other for 3 turns. Then some guns got damaged and I repeated for another 3 turns. So most shots were repeated shots which have a higher chance of hitting. In the non-hull down scenario, the Jumbo's got waisted in the first turn (lower hull penetrations) so I repeated that 1 turn 3 times. In this case a significant portion of the shots were first shots so they have a reduced accuracy. Anyway since I'm not an expert on hit chances of various tanks to each other (hull down or not) I chose to restrict my post to the hull down matter. To answer your questions. I'm not sure of the quality of the crew. I just took the default exp. level in the scenario editor (so I guess they are the same). The tanks were stationary for 99% of the time.

Charles,

Thanks for looking into this matter and for this great game.

Joeri