Section Leaders:
Fionn Kelly & Madmatt

Artillery Practices by the Major Combatants of WWII

 by: James Sulzen

In the European theater, artillery practice is one of the most fundamental doctrinal distinctions among each of the major combatants of WWII. Even if no other national-related distinction is made, any good tactical game must account for the different ways each of the major belligerents used their artillery (IMHO). Let me try to briefly (for once? :-) describe the differences in which the major combatants performed fire missions with their artillery (as opposed to how they organized and deployed it).

Most everything I have to say here is derived directly from a lecture I heard at the Origins gaming convention in San Jose two years ago. Unfortunately, I cannot find my notes or the hand-outs from the lecture (my crazed filing system, I'm afraid), and I especially regret that I cannot properly accredit the gentleman who gave the talk. He was extremely knowledgeable and incredibly entertaining and what I learned at the talk I have not seen ANYWHERE else. Drives me crazy because I've been looking for corroboration since, and I cannot believe data so fundamentally important to understanding the dynamics of WWII combat is not readily available. Maybe somebody could point me to a good source that will verify (or refute?) what I say below. (BTW, I do not believe Bruce Gudmundsson's "On Artillery" covers the following in any meaningful detail; it was a major disappointment to me to find such detail missing. To be fair, as I remember it, Gudmundsson cites another source that he claims does have much detail not covered by he himself.)

Impromptu Fires  

What I will cover below relates to unplanned "impromptu" fires, as opposed to the pre-planned and plotted fires delivered prior to an expected offensive. The pre-planned fires tend to be a special case of impromptu fires. Note also that the descriptions below largely tend to apply to relatively long distance howitzer fire. Mortars for instance, tended to use other techniques, such as walking shots into the target. Also, note that all nations had several techniques, and that each of the nations could and did make use of techniques used by the other combatants (except that nobody but the U.S. used the U.S.'s system).

German Artillery Practices

Germany had what most game designers (certainly among micro-armor aficionados, anyway) regard as the "typical" system. There are specially trained Forward Observers (FOs) associated with each artillery battalion. The FOs are detailed to be with and travel with advanced elements which are being supported by the particular artillery battalion. For communications back to their artillery, the FOs had either a radio, or in the German case, more often a wire line strung out behind them going ultimately back to the battery. Yes indeed, I did say "wire". Apparently German artillery was a distant third behind the Luftwaffe and panzers for radio-communications equipment, and they had a wire-based system which they knew how to make work.

The position of the firing battery had to be surveyed to precisely locate it on a map. By survey, I mean the time-consuming whole nine yards of using transits (surveyor's telescope) and the like along with the hand calculations to get the battery's precise position on the map. Thereafter, the FOs, survey teams, recon units or whatever, would further survey major terrain features (whenever possible), and further add new "known" positions to the map back at the artillery HQ. These locations became "firing points".

To call for fire, an FO had to scurry off to one of the firing points, and take an angle and range estimate to the potential target from the known firing point. Because of the need to do spotting from known points, and the technical training required to be part of this fairly complex system, only specially trained FOs were ever likely to call for impromptu fire support (I believe). The data was called in to the firing battery over the wire. Human computers back at the battery then did the trigonometric calculations (by hand or maybe with limited slide rule assistance) to calculate where on the map the apparent target was relative to the firing point, and from that then calculate the apparent angle and range to the target from the firing battery. Part of the calculation was to factor in the meteorological data (apparently even a slight cross-wind can hopelessly throw off the accuracy of a shell fired through miles of the troposphere and stratosphere. Other variable also had to be factored in (gun wear, temperature, gun caliber, munitions type, etc. Now the battery was ready to fire one spotting round. Time from initial call-in to first spotting round: Approximately 15 minutes. Then if the spotting round's explosion was visible to the FO, the FO could correct (i.e., "left 200, down 400 yds") and another spotting round fired and so on until one fell "close enough". At this point the FO could do the call for "fire for effect" and the entire battery and/or batteries could open up.

One major problem of the above system was that apparently even trained observers tend to have something like 20% errors when estimating ranges from the observer's position to a target. Along with all the other potentially unrecoverable errors (variable winds, uneven terrain, etc.), this could lead to some pretty wild initial spotting rounds and therefore to even more delay in delivering effective fire.  The calculations for subsequent spotting rounds could usually be made much more quickly than for the initial round because it was likely the corrections would be relatively small. Therefore simple linear interpolations could be used to fudge to an adequate firing solution. Given that typical time of flight is something like 30 seconds, and needing several additional minutes for the necessary communications, calculations, and gun laying, I'd guess maybe 3-5 minutes is required for each extra spotting round.

However, when the artillery came down, it landed pretty much where Jerry wanted. In other words, the concept of "drift" should have been largely irrelevant to an impromptu German barrage. On the other hand, however accurate the barrage may have been, given the above process, you have to figure a savvy target might have some idea what was coming.

The only really good thing you can say about the above system is that it was much better than what had previously existed. In World War I practice, it was virtually impossible to do impromptu fires unless the firing battery could directly see the target. So in comparison to WWI practice (and to Russians), the German system seemed quite good, and even had some advantages over the British system. (Like accuracy; but I get ahead of myself.)

Of course, a battery could always engage in map fire (also known as blind fire) where essentially no reliance is placed upon initial spotting rounds. This apparently tends to result in fairly inaccurate results and tends therefore to be limited to harassing fires. It's probably reasonable to allow for some sort of "drift" factor in the context of a game when engaging in such fire.

There are several optimizations to the above process to speed the delivery of effective fire. First, any previously targeted location could have fires very quickly brought against it because all previous firing data was logged and could be easily re-used (you'd better believe they saved that data, given what a bother it was to calculate). Also, fire could be fairly quickly and accurately delivered against targets located near a known firing point (read that as: "near a previous target") because the necessary calculations were relatively easy to perform to correct for small target location changes. Consequently, if most of the places the Germans needed to shoot at could be ascertained ahead of time, there is little reason to see why individual German batteries could not fire as effectively as U.S. artillery (see below).

In a prepared defense (or in a prepared attack) the battery could in theory have any number of pre-plotted firing points so that effective fire could be quickly delivered as needed. This technique is also known as "registered" fire (the pre-plotted locations being considered "registered"). Even in a hasty defense, defending units probably tended to have at least a few firing points to cover the more obvious lines of attack and could call in fire request via wired phone (a much more reliable communications method than the radios of the day).

British Artillery Practices  

The British had a very different system. They gave their people (artillery and FOs) good maps with grids marked on them. The artillery would plot its own grid coordinates when it set up. To request a fire mission, the FOs would call in the grid coordinates of the target to the artillery. Then to calculate firing distance and angle, the artillery simply assumed that the earth is a perfectly flat, infinite plane (take it from me, it ain't) and did the standard (7th grade?) calculation:

distance = SQRT( (x1 - x0) ^ 2 + (y1 - y0) ^ 2)

and similarly for the angle calculations (SOHCAHTOA if I remember the mnemonic for the Law of Cosines from high school trigonometry).

The British could then fire spotting rounds and correct just like the Germans, but this would have required sticky arithmetic calculations, even if only linear interpolations. Also there's the time delay to work all those formulas out. So instead, the British just accepted the errors and tended to fire every available battery at the target. Since each battery's fire would tend to be somewhat in error relative to the other batteries, this had the useful effect of blanketing a large area around the target, as well as the target itself. (And probably any Tommy close enough to observe the target.)

The British were ignoring a whole host of errors that the Germans carefully accounted for (elevation changes, wind, temperature, etc.). By using many batteries, they could get a large enough area covered so that they would have a reasonable effect on the target. Also, they got their impromptu fires really quickly: Something like two minutes from the time of the first call until those shells are bursting everywhere.

There are a few major drawbacks to the above system. While fast it is not accurate, wastes a lot of ammo, and ties up a lot of division artillery assets. Also, it requires accurate maps with many terrain features accurately located on the map (i.e., cross roads, stream beds, towns boundaries, etc.). The British tended to assign fairly senior NCOs and experienced personnel in the FO role so that they wound up mitigating the problem somewhat of wasting ammo (i.e., the more experienced FOs had good judgment as to what was and wasn't a worthwhile target). Also, it seems that only FOs called in missions (at least that is my impression).

I presume (but have no specific references) that the British could have and did use the German system of setting up registered fire when they had occasion in more static situations. Also I should mention my reservation that I have a hard time believing the allegation that the British habitually fired an entire division's worth of guns (more or less) for each fire mission.

On a slightly different topic, the following occurs to me as an explanation as to why the British may have suffered high tank losses over and over to German AT guns in North Africa (especially during Rommel's heyday). It could well be that the above British artillery practices prevented effective fire against the dug-in AT guns. Without good maps (it was North Africa after all), accurate fire may have been very difficult to obtain in a fluid situation. The ultimate result being that the British felt the only way they had of dealing with the guns was by using their tanks. If true, this is another example of failure of combined arms tactics on the part of one side and successful employment of it on the other side. Just wildly speculating here - flame the idea, not me.

American Artillery Practices  

Americans used the British system, but with a very significant innovation. They pre-computed the firing data for a HUGE number of variations of wind/temperature, barrel wear, elevation differentials, etc. Then for each possible variation, they created a separate calibrated tape measure. Along the tape was printed the gun laying information instead of distance marks. When a firing mission came in, the plotting officer would simply go to a filing cabinet containing the hundreds (thousands?) of these tapes and pull out the correct one for the current meteorological and situational factors. Then the tape would be laid out between the two grid points on the map (the battery's and the target's) and the firing data would be read from the printing on the tape. Apparently there were some other fudges that got thrown in to make the firing even more accurate.

Net result was that there were about three minutes elapsed time from the initial fire support call until shells were making the enemy duck. And the firing was almost as accurate as the spotted German fires. Ergo, very responsive explosions exactly where they are wanted.

Again, a drawback to the American system is that it requires very accurate and detailed maps (say showing individual farm buildings for instance) which must be plentifully supplied to troops at all levels. However, given the availability of such maps then American artillery could be hellacious.

I might guess that temporary lack of such maps may be a reason why certain obvious movements were tardy during the pursuit across France. How would you feel about moving into an area where your artillery could not fire (because the forward troops as well as the artillery had no maps with appropriate grid marks)?

The tape measure system was not the only innovation of the Americans, as there were several others that followed directly from the simplicity of the tape usage.

Since the grid system was so easy to use for calling in fires, it was standard doctrine to train all officers in it (and many enlisted men as well?). In fact the technique was so easy, that an otherwise ignorant enlisted man could be readily walked through the procedure over radio (and was on more than one occasion) when all his officers had fallen.

Another trick of the Americans, as Jim O'Neil has recently posted in detail, was the Time on Target mission (TOT). With this one, every battery in range was told the grid coordinates of the target and time when all shells were to initially land at the target. Each battery did its normal firing computation and then calculated the time to "pull the lanyards" by backing off the time-of-flight from the target time. TOT was particularly nasty because the initial shell from every gun landed virtually simultaneously before any defender could take cover. It took too much effort for the Germans to care much for such a technique, and the British were not accurate enough to make the technique particularly useful. Very nasty and only Americans could pull it off (Jim claiming it required as little as 10 or 20 minutes preparation).

Another innovation of the Americans was their ability to obtain accurate fires extremely quickly from a LARGE number of firing batteries. Because of the simplicity and elegance of the tape system, almost any battery in range could fire on any target in any direction. All they had to do was get a request from another firing HQ or even just listen in on other battalion radio nets ("Hey, Red Bravo Two, we have a situation at grid coordinates such and so").

This system was formalized by having a fire mission request being kicked "upstairs" if warranted for a suitably attractive target. The firing artillery battalion might contact the division which then might also request support from corps. Ostensibly, the inclusion of the division support added an additional three minutes to the fire mission, and including corps assets added three minutes yet again. There apparently was one case in Italy of a piper cub pilot (an artillery spotter) calling in no less than five corps level missions in one hour (this extremity of fire concentration was of course EXTREMELY uncommon, but certainly not unheard of).

Such relatively spontaneous massing of fires was absolutely not true of the German system which required a careful pre-plotting by surveyors to figure out where things really were on the map. In some sense, all American batteries wind up in general support (can fire for anybody). Consequently a given fire request may pick up extra "idle" batteries to thicken the fires. And during emergencies, any battery in range could leap into the fray to save a Yank ground pounder's tail.

Beyond the above "standard" organizational doctrine, apparently Americans were quite capable of concentrating fire support on as large a scale as needed. I'll offer an example from the German counter-attack at Mortain in August of 1944 (from Saving the Breakout, Alwyn Fetherstone, 1993). Three American infantry companies were trapped by the Germans on top of a hill overlooking the valley that Mortain lies within (this was a bottle neck that a major part of the German attack had to pass through, if it was going to cut off Patton's breakout). The American infantry held out for something like two days against the better part of a panzer/panzer grenadier division that desperately wanted the lousy Yanks off of the hill. The only problem seems to have been that some twelve and a half battalions of Uncle Sam's artillery could be called on in the instant by the infantry, anywhere on the highly visible countryside for miles around. This not only prevented all daylight movement by the German attack, but completely thwarted any attack on the infantry itself, even at night. To imagine the effect of being a German attacking up that hill, think of being on a football field with some fifty to one hundred 20-odd pound TNT explosions going off around you EVERY second (some two hundred guns each firing every 3 to say 8 seconds). Another way to think of it is to say that, in some sense, you might expect to have a shell land within touching distance of you every 15 seconds or so. Yep, I don't think the US needs to bow to anybody when it comes to an ability to deliver impromptu concentrated fires

By the way, as a side note, no artillery gun anywhere (in the US Army at any rate) ever fired more than about 800 rounds in any day (Trevor Dupuy, Search for Historical Records of High Rate Artillery Fire in Combat Situations, 1978). This was the extreme high, and a more typical high for any given battery is likely to be on the order of several rounds per gun per day. Apparently logistical limits more than anything tended to prevent firing a larger number of missions.

No doubt more than one German officer assumed he'd have at least the first 15 or 20 minutes of his surprise attack free of defensive artillery fire. And when the artillery did start to come in, he'd expect to be warned by the initial spotting rounds. Instead he found he was under immediate fire placed directly on his men while many were still crossing the start line. I'm sure it appeared to more than one German that the Americans must have known when and where such attacks were coming. No wonder some Germans were impressed with American artillery.

Soviet Artillery Practices  

I am not sure my information may be as reliable regarding Soviet practices as it is with the American or German. Also, I would not be surprised, as in so much else, that much of the Soviet practice significantly changed during the course of the war.

Having said that, let me venture the following as my understanding. Apparently the Soviets had very limited ability to call in impromptu fires. As the guy giving the Origins lecture said (more or less), "If Ivan knew how to do those calculations (that any German high school graduate was capable of), then they did not waste him firing artillery, but put him to work designing aircraft." Possibly apocryphal, but somehow telling.

Therefore I'd postulate that in prepared, and certainly observed fires, the Soviet artillery should be able to be reasonably effective (i.e., accurate and timely). However, once the situation turns fluid, and the front starts to displace, Soviet artillery fire probably becomes almost useless except where the artillery itself can see the target and correct its own fires. In essence, this mirrors the World War I experience of well-planned initial fires, and slackening effect as troops move forward (especially in fluid situations). Regardless, the general take is that by late '43 Ivan is rolling in barrels of batteries, and is indeed evilly equipped in '44 and '45.

Again, the above is just my best guess, and the Soviets may have been able to adopt some other system as the war progressed, especially for mobile operations.

How this Affects Wargames

You can see from the above, that in a tactical-level wargame one would expect each nation's artillery to be governed by rather varied rules. The Germans get accurate artillery, but it's somewhat slow to come. The British get the fire very promptly. Their fire is less likely to seriously damage the intended target, but the effect of the barrage is going to be spread over a much wider area than a similar German or American fire mission. Furthermore for the most part, for the British and Germans, only specially trained Forward Observers can call in artillery fires.

The Americans of course get it all: Fast, deadly accurate (i.e., little or no drift), they get extra when they care (and even if they don't care), and they get the additional potent weapon of Time on Target. I should also mention that proximity fuses were introduced (sometime during the Bulge, I believe) so that Americans then can start getting the benefit of the far more deadly airburst fires (deadly to infantry and especially to open-topped vehicles).

Note that when in any kind of prepared defensive position, I would expect the British and German artillery to start responding as quickly and accurately as American. However, I suspect that the British and Germans may still have been limited to only FOs calling the artillery, even when in defensive positions.

Lastly, depending upon the period of the war, probably get a ton of not tremendously accurate, but decent artillery (again the amount and quality of fires will vary enormously during the course of the war). In a mobile situation they are probably largely limited to line of sight firing (maybe this is one of the reasons why they liked relatively big mortars so much?).

Another effect I might expect is differences in relative setup times for deploying artillery into new positions. British and American artillery should be fairly quick to get setup, being only really limited by having to set up the equipment, connect up their communications links, and lay in ammo. The Germans should require more time (unless all survey prep was done prior to the move) because the new position has to be surveyed, and the survey results have to be tied into previous results. Also the German artillery seems to have been rather more dependent upon wire communications than were the Western Allies, and so may be further delayed because of this. I cannot speak at this point to what the likely limits are which affect Soviet setup.

Now that I think of it, the utility of German and Soviet artillery "divisions" probably existed in the ready ability of such a division's firing elements to share survey results and coordination within itself. Contrawise, the difficulty of tying survey results together across artillery organizations strikes me as an additional complication that enormously hinders quick massing of German and Soviet artillery battalions, such as occurred with the Americans at Mortain. It's not that the Germans and Russians could not as effectively mass their artillery fire, but that it would take a lot longer because essentially everybody's map would have to be calibrated against each other. Again, I'm just speculating here.

Author's Footnote:

I said that the American's had developed a system of using many (as in thousands of) highly customized "tape measures" to measure map distances and thereby semi-automatically do artillery calculations. (I.e., one tape was calibrated for "wind from the NE at 6 mph", another tape for "wind from the NE at 7 mph", etc. and other tapes for wind from NW, wind from W, etc.). Apparently, what the Americans really did is simply read correction values from a humongous set of precomputed artillery tables (books really). The source I quoted, a lecture I heard at a conference, probably said something like "it's as if the Americans had thousands of specialized tape measures" and I missed the "it's as if" part of the lecturer's statement and thought he literally meant that they utilized pre-calibrated tape measures to read artillery tube settings directly from the tapes. Oops. A minor detail, but a rather telling one.