Quote Originally Posted by Compost View Post
However believe there are good reasons for organising such mortars into two or more sub-units. Such organisation firstly enables a battalion to have a mortar sub-unit firing or emplaced/ready to fire while its other mortar sub-unit(s) are moving in leap-frog or other manner.
Even platoons can be separated like that. Leap-frogging is probably a lesser reason for this need than the different range and bearing dispersion and the need to reach behind obstacles (hitting a street behind a large building, steep rear slope).

Two 4-tube platoons with 81mm mortars might be enough firepower for most light infantry battalions.
I never quite understand why people pay attention to mortar tube quantities so much. Mortars can shoot at up to 16rpm, and electric laying systems even permit a fine accuracy at such a RoF.
The greater issue is in my opinion the ammunition supply. Even mechanised forces may be limited in their indirect fire support first and foremost by ammunition carried, not by tubes carried (since mechanised spearheads got to expect resupply only every 2nd day on average).
Infantry with more limited carrying capacity (especially in airborne / heliborne / mountain / swamp context) needs to look at ammo carried more than tubes as well. 81.4 mm mortars may be crew-portable, but their ammo is portable only in very restrictive quantities, even with a few mules.

Realise that some commentators prefer 6-tube mortar sub-units and the redundancy of 3-tube sections. Others might insist on the need to standardise on either 81mm or less likely 60mm long-barrel. Believe that very few would propose 120mm smooth-bore mortars for a light infantry battalion and that none would propose 120mm rifled mortars.
120 mm rifled mortars can actually fire 120 mm smoothbore ammo and as far as I know their only real drawback is their higher weight.

120 mm has probably passed its prime since the cluster munitions ban (smaller calibres = more efficient in terms of fragmentation effect divided by ammo weight). It is nevertheless the standard calibre for almost all guided mortar munitions and thus a must-have for well-funded ground forces.


The challenge is as usual to get a long list of things right
* leader training
* technical personnel training
* grunt training
* training with vehicles
* security training
* qty of ammunitions in national stock
* quality and age of ammunitions
* signatures of propellants (smoke / flash)
* quality and reliability of fuses
* qty ammunitions carried
* composition of ammunitions carried (enough smoke!)
* resupply with ammunitions
* communications reliability - radio, cable
* communications prioritisation
* encryption/decryption/authorization
* spacing barrel-radio emitter-other personnel or shoot&scoot for survival
* observer training (not just dedicated forward observers)
* observer authority
* observer equipment
* qty of tubes
* heat transfer and thermal capacity of tubes
* tube laying system
* deconfliction rules
* RoE
* authorised personnel strength
* actual personnel strength
* sleep deprivation, sleep discipline
* anticipation of mortar support needs
* location of tubes relative to target, friendly troops/civilians and obstacles
* readiness / reaction lag
* nighttime effectiveness / illumination
* camouflage and concealment


The qty of tubes almost disappears in this list of important factors and is definitively not #1.