Accuracy While Firing On the Move (OR FAST) in CMBO

[zahl]

1000m in 103 secs would be

1000/103=9.7 m/s

9.7*3.6=34.95 km/h

34.95/1.609=21.7 mp/h

I tested Hellcat's cross country speed on the fast move and got about 20 mph.

[Fangorn]

1000m in 103s = 9,7 m/s x 3,6 = 34,92 k/h.

Yes, your math is wrong, happy now?

[aka_tom_w]

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

1000m in 103s = 9,7 m/s x 3,6 = 34,92 k/h.

Yes, your math is wrong, happy now? <HR></BLOCKQUOTE>

Thanks

I figured someone would correct my LAME math

But I tried

Now where is that Great big cup of Shut Up I was looking for

Sorry Steve, I was mistaken, I offer my apologies.

-tom w

[L.Tankersley]

[Heh, looks like I was a little late off the mark here.]

[While I'm editing this, I want to bring up a possible "abstraction" rationale for the ability of CM vehicles to fire while moving "Fast." Remember that actual vehicles are not restricted to three discrete speeds (Move, Hunt and Fast) but can also move at intermediate speeds and speed up and slow down relatively quickly. Consider the following scenario: a tank is moving fast when it spots and decides to engage a target. The gunner/TC yells "slow down a sec so I can fire!" The driver reduces speed for a few seconds. Once the round is on the way the tank quickly speeds back up to maximum speed and continues on while the gun is reloaded. While I don't really know anything about acceleration/deceleration speeds of WWII vehicles, this doesn't seem all that unreasonable. It is not explicitly modeled in CM but if it makes you feel better you could imagine it is going on "behind the scenes."]

Your math is wrong. You multiply minutes by minutes to get kph; this is a no-no.

Here it is another way:

1000 m / 103 s = 9.7 m/s

9.7 m/s * 3600 s/hour = 34950 m/hr ~= 35 kph

35 kph / 1.6 km/mile ~= 22 mph

[ 07-26-2001: Message edited by: L.Tankersley ]

[Slapdragon]

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

Thanks

I figured someone would correct my LAME math

But I tried

Now where is that Great big cup of Shut Up I was looking for

Sorry Steve, I was mistaken, I offer my apologies.

-tom w<HR></BLOCKQUOTE>

Tom, that is what these threads are for. Everyone makes a little mistake. You go and test your theories, post your results, and don't wiff if they get a little beaten. I think you deserve a silver star.

[aka_tom_w]

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

Tom, that is what these threads are for. Everyone makes a little mistake. You go and test your theories, post your results, and don't wiff if they get a little beaten. I think you deserve a silver star.<HR></BLOCKQUOTE>

I never been really good at math and I knew when I posted the caculation seemed suspect given that the top speed of the Hellcat is supposed to be 55 mph.

BUT the 103 sec over 1 km WAS accuratly recorded and double checked, my Lousy Math skills screwed me up, but i really did figure that some here would do the math right I just did not want to ask someone else to do the calculation for me so I tried my self. Ooops!

Oh well I guess that kind of accuracy at 23 mph at 250 m was historically accurate for the Hellcat. Its still fun to fly down the flanks and attempt to envelope and out flank heavy German tanks with.

And no, no silver star was earned for Lousy math skills but thanks

-tom w

[Slapdragon]

Yes, there are documents recording <somewhat> accurate shooting at 20 mph, and 25 mph, although officially faster than its drive governor would allow cross country, was well within the frame and the engine's reach (realizing that without the governor it could travel faster than the speed limit (55 mph) on US Federal defence highways.

Much more than that and you would be seeing some problems because cross country it was actually too light to handle major bumps.

In fact, what the crews liked most about the Cat was its acceleration, twice that of the Sherman, more than the flat out speed it could shoot at.

[aka_tom_w]

AND

Of course lets not forget to mention:

"Let this be a lesson for anyone who tries to get away with lame-ass math skills, wrong calculations or EVEN bad or incorrect historical military data or facts from WWII....."

The accurate and correct data or calculation WILL, without a doubt, appear on this board BEFORE you even have time to edit the original offending post, claim, fact, or calculation.

And this is a testament to the devotion of this community. I thank all of you who posted so diligently to correct my calculations which were clearly in error.

Thanks

-tom w

[ 07-26-2001: Message edited by: aka_tom_w ]

[ 07-26-2001: Message edited by: aka_tom_w ]

[Battlefront.com]

Hey Tom,

We all make mistakes. The important thing is to understand that and look beyond them. Now that you (and others who share your opinions) have seen a fairly factually based counter discussion, what say you?

In my opinion these are the points, counter points brought up in this (and another) thread.

1. Firing on the move using FAST does not offer much of a penalty - my tests clearly show that even at point blank range this is not true. At longer ranges it is night and day different compared to firing while halted.

2. Tanks should not be able to fire on the move - historical accounts beg to differ. In fact, especially with the Soviets, this was SOP for armored vehicles on the advance.

3. Firing on the move was very difficult - yup, which is exactly what the stats show. But it doesn't mean it wasn't done simply because it was difficult.

4. AFVs should not be able to fire while going at top speed - again, there is no basis for this. In any case, Fast does not mean the vehicle actually acheives its top rated speed. Generally the speed is actually only 10-20mph over perfect open ground conditions.

5. Gyros add a huge advantage to a tank which has one - not true. At most it adds a couple of % points to the chance of hitting, but since firing on the move is already rather poor, it doesn't result in a massive difference between a non-gyroed vehicle.

6. Do moving vehicles get an accuracy penalty due to the impossibility of bracketing? - you bet. Each shot fired is treated like a "1st round" since it is highly unlikely that the TC is going to spot shotfall or be able to quickly calculate aiming corrections while bouncing around in the turret.

Uh... did I miss anything?

Steve

[zahl]

<BLOCKQUOTE>quote:</font><HR>Originally posted by Big Time Software:

BTW, I did get a chance to check with Charles. In an example he gave me a gyro *might* increase a specific vehicle's chance of hitting from something like 10% to 14% while on the move.

<HR></BLOCKQUOTE>

That is a very significant improvement, a 40% increase. Or 4 percentage points.

Maybe the gyro bonus is dependent on speed and is greater when driving faster? The difference in accuracy was afterall close to 1.9x, although the difference in speed was only about 1.5x.

What's more interesting is the good accuracy of the fast moving E8, 43%. This is clearly superior to the Hellcat, be it for whatever reason. The gap is also more narrow, 76% vs. 43%. It is quite difficult to be believe that a real world regular crew in that fast moving (13 mph) E8 could score a hit almost half of the time at 250m.

[zahl]

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

I did a test comparing two 75mm armed tanks, one with Gyros (M4) the other without (Cromwell).

...

The gyro equipped tank gained an 8% advantage at 400 meters, but I only did 10 runs, so I have a bit of error in there.

<HR></BLOCKQUOTE>

You mean an 8% advantage or an advantage of 8 percentage points?

[Battlefront.com]

Zahl,

<BLOCKQUOTE>quote:</font><HR>That is a very significant improvement, a 40% increase. Or 4 percentage points.<HR></BLOCKQUOTE>

It is a significant improvement relative to not having a gyro. Uhm... which is the whole point of going through the expense and trouble to create, install, maintain, and train the crews However, it is a negligable improvement when compared to a vehicle firing from a halt. In other words, the bonus is rather small in terms of battlefield effects. The chances of a miss are still great, even with the 4 extra points added.

<BLOCKQUOTE>quote:</font><HR>Maybe the gyro bonus is dependent on speed and is greater when driving faster? The difference in accuracy was afterall close to 1.9x, although the difference in speed was only about 1.5x.<HR></BLOCKQUOTE>

The relationships are not linear, so your comparison is not valid. The faster you go the worse the accuracy is per MPH of speed increase. And as I said before, the gyro bonus is not enough to yield such a huge advantage.

<BLOCKQUOTE>quote:</font><HR>What's more interesting is the good accuracy of the fast moving E8, 43%. This is clearly superior to the Hellcat, be it for whatever reason.<HR></BLOCKQUOTE>

Vehicle weight is also a factor. The Sherman is nearly 2x as heavy as the Hellcat, which means it won't bounce as much at high speeds.

<BLOCKQUOTE>quote:</font><HR>The gap is also more narrow, 76% vs. 43%. It is quite difficult to be believe that a real world regular crew in that fast moving (13 mph) E8 could score a hit almost half of the time at 250m. <HR></BLOCKQUOTE>

The key element here is the range. If you have some data to back you opinion that this is too generous, we are all ears. But from previous debates we have had about this issue it seems to us that 13mph, pointblank, high velocity, flat trajectory gunnery is not that much more subject to error than stationary gunnery. At least not against a rather large target like a Panther. Change the target to a MG Team and I think you would find that the moving Easy 8 misses a heck of a lot more.

Steve

[Stephen Smith]

I don't think I'll be contradicting myself when I say that there is an important difference between modern tanks and early war tanks that may impact the 'firing on the move' debate-and that is the difference in shell size. On a modern M1, the 120 mm shell weighs about 45 lbs, and is 1 1/2 to 2 feet long. It is large enough and unwieldy enough that it is difficult to even load (the loader has to practice a very specific movement to release the round from storage, where it is stored pointed backwards, lower it into his lap, shift the weight forward and aim the round forward, and lift it up again and load it into the gun tube-it was so difficult, it was common practice in a platoon to use the best loader to load for all four platoon tanks as they went downrange one after the other-not everybody is good at manhandling 45 pounds). M1s carry about 40 rounds, only half of them immediately accessible by the loader. So firing off 'suppressive' rounds isn't really feasible (1 shot 1 kill was ALWAYS the goal).

On early war tanks (thus, early war British and Russian-who we are talking about), the rounds, I'm sure, are MUCH MUCH smaller: 37 mm, 50 mm-I bet a loader could pick one up with one hand, and load it in. I am guessing a tank could store far more rounds (I bet even a 75 mm round is much lighter, much shorter, and much easier to handle). Thus, it is feasible to fire alot of rounds from an advancing company of Russian tanks into a woodline, hoping to keep the heads down and maybe occasionally get lucky and hit something. As to whether they would actually hit anything, I am skeptical. But the entire concept of 'suppressive' fire would be different from such an easily handled round than it would be with a 45 pound round in modern vehicles.

steve

[Battlefront.com]

Hi Steve,

Good points. The loading aspect, as you say, is probably very different today compared to yesterday. Also, as you say, the role of the tank's main gun has also changed. M1A1s don't even have HE if I am not mistaken.

Whether the tank could hit on the move or not is highly situationally dependent. In general, firing while on the move most likely would not result in a hit. However, in ideal circumstances (high velocity gun, flat terrain, dry ground, clear weather, unobstructed LOS, already spotted enemy, big target, no return enemy fire, and CLOSE RANGE) I think there would be a decent chance of scoring a hit. And since the tests I did were under the BEST circumstances possible, I think it is fair to say that in general the chance of a hit will be far less.

In fact, I just went into my test scenario, put the Panthers in Scattered Trees, made the terrain slightly uneven, and let the Hellcats run loose at 250m. They only got off 3 rounds TOTAL, none of which hit. This is compared to 14-16 shots and 2-6 hits in my ideal test situation.

In other words, you are talking about it being unlikely to score a hit in an average real life battle situation while on the move. I agree. My previous tests were more like Firing Range conditions. Even adding a few elements, like scattered trees, really changes things.

Steve

[Slapdragon]

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

You mean an 8% advantage or an advantage of 8 percentage points?<HR></BLOCKQUOTE>

If 100 tanks fire at 100 medium targets, the 75 with the gyro was getting 8 more hits per hundred fires than the one without.

[Treeburst155]

My Test:

4 green PZ IVs, ammoless, buttoned, and facing the edge of the map in a corner of their setup zone 40 meters apart.

One regular M5A1 gyro Stuart starting on one end of his setup zone and ordered to fast move the entire length of it. Trees prevent LOS to the Mark IVs for 200 meters allowing the Stuart to get up to speed. No other units on map. The Stuart must spot the PzIVs himself. The map is pool table flat with no obstructions other than the row of trees that allow the Stuart to get up to speed before spotting can take place.

Each test was two minutes long. I ran it 10 times. The Stuart spotted at least one of the Mark IVs by the last 15 seconds of the first turn in all cases, having cleared the trees. Since fast move orders were already given I just hit GO for turn two. The map was long enough that the Stuart could travel and fire the entire second minute without running out of map.

The Stuart hit an enemy tank 33 times out of 107 shots at ranges varying from 450-620 meters before the end of turn 2. 5 of these hits were track hits. The Germans used smoke in the latter half of turn 2 and began moving too.

A regular crew, moving fast, off road, hit with almost 31% of their shots. I think this is quite a high percentage, even with a gyro. What should the percentage be? I'd be happy if it were reduced to 10% but I'll bet 5% would be even more realistic.

[opfor6]

I have fired gunnery in M60A1,M60A3,M1,M1A1,Leopard 2 and Bradley. Of these only the M60A1 was not fully stabilized. In most cases a stationary vehicle at 250 yards is going to get hit. Only if it is very rough would a crew miss a barn sized target like that with three shots. 13% or 14% (or 1.3 shots out of 10) is not very high given the risk the shooter takes getting that close and moving.

What is happening is players are making very "gamey" tactics to take advantage of the fact there is no morale in vehicle units. I seriously doubt I could convince very many crews in my platoon or company to race their tank or AC at some stationary Panthers in the hopes of getting a 13% silver bullet shot. It would definately be harder after the Panthers killed the first few as they broke from cover in their charge.

Allied TD crews were taught to move constantly. This was in large part due to the fact when you fired you drew attention to that area. If you fired more than once or twice from the same spot odds were that a highly trained enemy gunner would put a round into you. TDs did not have the armor to risk a hit. The Hellcats had the fast acceleration and speed to get from one firing position to another in a hurry. Not to make a dash at the enemy.

If my Panther get that close to Allied tanks he has made a mistake as well. In most cases I have had experience with in CMBO stationary tanks rip up moving ones. The exceptions have been when there have been ALOT of enemy tanks (30) and the percentages are real bad for survival(13% x 30= not good).

I agree with BTS that the code is correct for the scale. Moving 15-25 mph and getting a 13% chance of a hit at 250 yards is in the ballpark. The large drop off due to range is the key part. At 250 yards the target is much bigger and easier to track than at 400 or 500.

[Slapdragon]

<BLOCKQUOTE>quote:</font><HR>Originally posted by opfor6:

I have fired gunnery in M60A1,M60A3,M1,M1A1,Leopard 2 and Bradley. Of these only the M60A1 was not fully stabilized. In most cases a stationary vehicle at 250 yards is going to get hit. Only if it is very rough would a crew miss a barn sized target like that with three shots. 13% or 14% (or 1.3 shots out of 10) is not very high given the risk the shooter takes getting that close and moving.

What is happening is players are making very "gamey" tactics to take advantage of the fact there is no morale in vehicle units. I seriously doubt I could convince very many crews in my platoon or company to race their tank or AC at some stationary Panthers in the hopes of getting a 13% silver bullet shot. It would definately be harder after the Panthers killed the first few as they broke from cover in their charge.

Allied TD crews were taught to move constantly. This was in large part due to the fact when you fired you drew attention to that area. If you fired more than once or twice from the same spot odds were that a highly trained enemy gunner would put a round into you. TDs did not have the armor to risk a hit. The Hellcats had the fast acceleration and speed to get from one firing position to another in a hurry. Not to make a dash at the enemy.

If my Panther get that close to Allied tanks he has made a mistake as well. In most cases I have had experience with in CMBO stationary tanks rip up moving ones. The exceptions have been when there have been ALOT of enemy tanks (30) and the percentages are real bad for survival(13% x 30= not good).

I agree with BTS that the code is correct for the scale. Moving 15-25 mph and getting a 13% chance of a hit at 250 yards is in the ballpark. The large drop off due to range is the key part. At 250 yards the target is much bigger and easier to track than at 400 or 500.<HR></BLOCKQUOTE>

Well, Hellcats would dash from cover to cover, but SOP was to fire like hell as they dashed if they were in contact, otherwise they would try to be quiet.

The accelration was a major key here. Three of the Hellcat crew could help with the firing, so firing madly and running were their big defence. The crews were very aware they were in a death trap with no arnor if they stuck around.

On the other hand, running at full speed right at the enemy was not SOP. They preferred to flank or cross.

Part of the odd US TD tactics was that the TD command had been designed to soak up armored attacjs, but were called on during ETO to fight in the attack, which made them more aggressive than a modern tanker with better armor may expect or be comfortable with.

[aka_tom_w]

<BLOCKQUOTE>quote:</font><HR>Originally posted by Big Time Software:

Hey Tom,

We all make mistakes. The important thing is to understand that and look beyond them. Now that you (and others who share your opinions) have seen a fairly factually based counter discussion, what say you?

In my opinion these are the points, counter points brought up in this (and another) thread.

1. Firing on the move using FAST does not offer much of a penalty - my tests clearly show that even at point blank range this is not true. At longer ranges it is night and day different compared to firing while halted.

2. Tanks should not be able to fire on the move - historical accounts beg to differ. In fact, especially with the Soviets, this was SOP for armored vehicles on the advance.

3. Firing on the move was very difficult - yup, which is exactly what the stats show. But it doesn't mean it wasn't done simply because it was difficult.

4. AFVs should not be able to fire while going at top speed - again, there is no basis for this. In any case, Fast does not mean the vehicle actually acheives its top rated speed. Generally the speed is actually only 10-20mph over perfect open ground conditions.

5. Gyros add a huge advantage to a tank which has one - not true. At most it adds a couple of % points to the chance of hitting, but since firing on the move is already rather poor, it doesn't result in a massive difference between a non-gyroed vehicle.

6. Do moving vehicles get an accuracy penalty due to the impossibility of bracketing? - you bet. Each shot fired is treated like a "1st round" since it is highly unlikely that the TC is going to spot shotfall or be able to quickly calculate aiming corrections while bouncing around in the turret.

Uh... did I miss anything?

Steve<HR></BLOCKQUOTE>

Hi Steve

Thanks for looking into this. I admit after we all looked at it again, and after I got my math calculation problem sorted out, that the firing on the move thing does not look as bad or "gamey", as I had originally concluded.

I agree with opfor6 when he posts:

"What is happening is players are making very "gamey" tactics to take advantage of the fact there is no

morale in vehicle units. I seriously doubt I could convince very many crews in my platoon or company to

race their tank or AC at some stationary Panthers in the hopes of getting a 13% silver bullet shot. It

would definately be harder after the Panthers killed the first few as they broke from cover in their

charge."

This does make sense because I send Greyhounds and Hellcats in ALL the time to get close for great flanking shots, and sure, I get alot of my tanks and crews wasted, so vehicle moral would probably prevent trying to get "that 13-30% silver bullet shot" to the rear or flank of a heavy tank. BUT its still FUN to try!

Vehicle moral in CMBB should be VERY interesting indeed. I can't wait!

-tom w

[ 07-27-2001: Message edited by: aka_tom_w ]

[WineCape]

What a good read in this thread!

Regards,

Charl Theron

[Andrew H.]

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

Much more than that and you would be seeing some problems because cross country it was actually too light to handle major bumps.

<HR></BLOCKQUOTE>

Hmmm. I wonder if CM should model a (small) random chance that Hellcat traveling at full speed cross-country might hit a bump and fling the tank commander out of the turret. The sound file for this event could be based on the bridge scene from the Holy Grail.

Perhaps this should wait for the engine rewrite.

[Treeburst155]

No comments on my test? Look at that high hit percentage at 450-620 meters. I've got more than twice the hit percentage at twice the range mentioned by OPFOR in his post above. I didn't test Hellcats but look at the Stuarts! If I had the time I'd test those Daimlers and Greyhounds too. There's too much killing going on while bouncing cross country at 15-25 mph.

OPFOR6 wrote:

I agree with BTS that the code is correct for the scale. Moving 15-25 mph and getting a 13% chance of a hit at 250 yards is in the ballpark. The large drop off due to range is the key part. At 250 yards the target is much bigger and easier to track than at 400 or 500.

[ 07-27-2001: Message edited by: Treeburst155 ]

[Treeburst155]

A quick test of Hellcats convinces me they are virtually harmless at 500 meters while fast moving. This makes me happy. Stuarts however are a different story. It sure is tempting to blame it on the gyro-stabilizer. Perhaps the Stuarts are getting a break because their "fast" speed is lower. More testing is needed.

[Sergeant Saunders]

Every thing that I have read about the Stuarts touts the 37mm as a super accurate weapon. During the desert campaign the Grants with the same 37mm would fire it several times as far as the 75mm in the hull turret.

[Treeburst155]

Even a highly accurate weapon can't hit a target unless the gunner/shooter can put

the crosshairs ON the target. At 500 meters, over clear terrain, at 15-25 miles per hour I think the Stuart gunners should have just that sort of problem. Hit a PZIV one out of ten times under those conditions with regular crews? Yeah, that sounds plausible. However, my test showed a 31% hit rate under those conditions. I refuse to accept that as accurate modelling of a WWII tank with a gyro-stabilizer. It goes against my tanking experience in 1975-78.