Survivable brigade artillery: Light howitzer

A brigade of the line should be modestly ambitious, high end only in critical key areas (reliable instant communication in the field and ability to defeat any AFV type) and it can be designed to be very dependent on higher level support. This way we can force design a brigade of the line ('infantry brigade') that has the training requirements toned down enough that reservists can fill 99% of its jobs (all jobs except battalion CO, brigade CO and XO and some brigade HQ positions).

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It would be dependent on such support anyway, so the force designer can -in an act of self-discipline- drop the pretence that such a brigade could stand against a main effort attack on its own.

Long range artillery fires are amongst what can be outsourced to above brigade level. Supporting fires on several kilometres front width and several kilometres front depth on the other hand is an every day need and should be organic, thus more reliable.

There are two ways to address this; we could think at battalion level and require the range needed to support a battalion. This leads to a 120 mm mortar with usually much less than 10 km range.

To address a brigade sector with all indirect fire support weapons requires more range. How much depends on many factors. A brigade sector is often assumed to be about 20 km wide, which requires about 15 km effective (with acceptable dispersion!) range. That's more than 120 mm mortar offer.

One might say 155 mm could cover much more than that, but shells flying that far isn't quite the same as capability to support well at that distance. The dispersion gets ever worse with longer ranges (especially with RAP shells) and 155 mm shells have ceteris paribus a greater danger close footprint than 105 mm shells have. In combination, you could not give 155 mm fire support against targets close to friendly troops at much greater distances (if any greater ones at all) than with 105 mm guns.

You can expect a dispersion better than 0.3% of range (30 m shot length dispersion at 10 km shot range) and better than 1% of range left/right (with gun set after first shot, about 10 m shot dispersion left/right at 10 km shot range) from a modern 105 mm howitzer.

120 mm mortars are popular as battalion-level support, but they are largely unavailable for brigade main effort fires due to their short range (their time of flight and sensitivity to wind is bad at extended ranges). This makes them reliable organic weapons for the battalion commander, but suboptimal for the brigade. A brigade with 120 mm mortars would need howitzers (105...155 mm) as brigade asset to be able to move fires quickly in the whole brigade area of responsibility. 105 mm field howitzers can also be reliable organic assets; standing orders and hardcoded priorities in fire control software can ensure that a battalion in contact always has support by two ro three howitzers. A brigade with three infantry battalions and 18 105 mm howitzers would still have 12...14 howitzers available for the brigade CO's main effort this way.

Moreover, think of the typical frontline deployment of an infantry brigade: Either one infantry battalion forward and two behind or two forward and one in reserve. Brigade fire support that consists 100% of 105 mm howitzers could be 100% available in such dispositions, while 1/3 to 2/3 of 120 mm mortars would either be detached forward or unavailable for fires at most of the line of contact. A one battalion forward deployment also shows that this battalion's mortars would be overstretched on a 15 km brigade frontage.

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So let's look at 105 mm howitzers for affordable brigades of the line, brigades suitable for creating, holding and occasionally slowly moving a defensible (often entrenched) frontline.

105 mm mountain howitzer OTO Melara Mod 56

The old light (mountain) howitzer OTO Melara 105 mm Mod 56 may serve as an example. Its dimensions in travelling configuration are

• 3.65 m length
• 1.5 m width
• 1.93 m height (can be lowered to 1.55 m)

A more modern piece is the GIAT LG-1 Mk. III:

• 5.20 m length
• 1.85 m width
• 1.62 m height

Both fit into a normal European car garage, which has approx. the internal dimensions

• 5.5 m length
• 2.3 m width
• 2 m height

An ISO 20 ft container (which could be dropped in the landscape by the thousands) has the internal dimensions

• 5.89 m length
• 2.35 m width
• 2.39 m height
  

This makes it much more feasible to effectively hide with such a gun than with 155 mm or self-propelled guns.

I say it's possible to design a more modern light howitzer that fits this description:

• shorter than 5.4 m
• narrower than 2.2 m
  
• lower than 2 m
• fits into a typical European car garage
• fits into ISO 20 ft container
• boattail shell range no shorter than 10 km
• maximum elevation 70°
  

I strongly suppose it's possible to add these features without exceeding the dimensions

• integral accurate position- and northfinding equipment
• integral auxiliary drive (battery-electric or 2-stroke diesel or a hybrid of both) for moving on flat hard surfaces under own power forward/backward up to running speed
• hydraulic power from auxiliary drive can be used to raise the spades (getting them unstuck manually may take time)
• boattail shell range 15 km
• basebleed shell range 18 km
• burst rate of fire 12 shots in one minute (as have L118 and LG-1 howitzers)
• barrel (liner) durability (and carriage durability) better than 5,000 EFC (equivalent full charges)
  

without it becoming too big to hide, to difficult to move or unsuitable for a 4x4 SUV as towing vehicle.

This would give the howitzer fire support qualities against all line-of-sight threats that the friendly forces face. Most targets that are identifiable with small (highly expendable) quadcopter drones or mast-mounted sensors would be within range as well. Deeper fires would be left to 'real' artillery, while this 105 mm howitzer would be more of a 120 mm mortar (practical range less than 10 km) alternative. Some danger close fire missions would be executed with SatNav-independent trajectory-correcting munitions to reduce the dispersion in range.

The howitzer could hide in a partially destroyed building, a 20 ft ISO container, a concealed trench, a garage or in woodland. The crew could receive a fire mission, move the howitzer into firing position in less than a minute, fire twelve shots in one minute (first shot least accurate and possibly self-destructing used for setting and measuring muzzle velocity only, others benefitting of now embedded spades and measured muzzle velocity of first shot) and go back into hiding within up to 2 minutes.

The munition of such twelve shots would weigh less than 250 kg including fuzes and propellants. This means a transportation with some kind of wheelbarrows would suffice for 100 m, alternatively even a small car such as Suzuki Jimny could provide a platform for the munition, for a fire control laptop, a radio and also serve as a towing vehicle (towing capacity of Suzuki Jimny is 1.3 t).

It might even be possible to hide the gun inside a shovel-dug trench (with overhead concealment if not cover and a ramp). The gun's auxiliary propulsion might drive an onboard winch to pull the gun out of the trench easily and quickly.

Even a combination of counter-artillery radar, standoff observation drones and PGM for counterfires is not very effective if the opposition can move and hide its guns like this. You might need to hit 5...20 probable locations to hit one gun, and such guns are difficult to take out of action for good. The guns would be dispersed; counterfires could never hit more than one gun and its crew. Friendly forces and civilians would be banned in the general area and the gun would thus be deployed at a safe distance to important roads and villages.

So what would be the jobs of such brigade artillery?

• suppressing fires (105 mm is about as effective as 155 mm at this)
• destructive fires at soft targets of opportunity (single gun or few guns on point targets, massed fires on area targets), including fires on mortar teams and triangulated radio frequency emitters
  
• fires at marshalling areas
  
• (IR) illumination shots
• (multispectral) smoke fires
• leaflet (propaganda) fires
• occasional neutralising fires
  
• possibly shooting down observation drones if they are close enough (using proximity fuses)
  

This leaves especially deep fires, fires on hardened targets and most neutralising fires to the higher level artillery (divisional or corps artillery). This frees the brigade HQ of tasks, as they would not have to handle such activities. The forward observer teams and aerial observation would communicate targets for deep strikes and hardened targets directly o higher level fire support.

The brigade HQ would not pay much attention to what happens beyond about 5 km of its troops other than receiving warnings about incoming hostile forces. This limitation of the brigade HQ is possible and driven by not giving the brigade longer-ranged artillery (such as 155 mm howitzers or MRL) and it helps with allowing a slim, quick and largely reservists-staffed brigade HQ.

S O

defence_and_freedom@gmx.de

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