Self propelled Artillery has an important role on the modern battlefield, but the current trend is towards heavier and heavier systems that will compete with MBTs for airlift resources.
Modern designers may benefit by looking back a few decades and visiting sites such as Achtung Panzer. The main Werhmacht SPH system was the WESPE, an 11 ton vehicle mounting a 105mm weapon. A bit of background reading reveals that the howitzer used on the Wespe was heavier than the M119/ L118 in current service. It is therefore quite feasable that a modern version of the Wespe using a M113 body and a M119 gun could be built.
The usual argument against such a configuration is that the crew are not as well protected as those of a turreted, fully enclosed SPH. While this is true, it is more useful to look at it from the point of view that the crew are still better protected than that of a towed weapon, and have the protection of greater mobility too.
The light weight of this system would allow it to be heli-lifted, increasing the options available to a commander.
An interesting idea mentioned by Larry Altersitz in his G2mil article on airmobile artillery systems is that a flatbed M113 variant with a PLS-type loading system could carry a pallet mounted 105mm Howitzer. Larry may not realise it, but this is the German Waffentrager- Grille idea. The idea was to have a vehicle that could operate as an SP-gun but could also leave its weapon in a static position, the vehicle then serving as a supply tractor.
One capability of such a vehicle that would be useful now is that the gun and its transport could be moved by separate helicopter lifts. The system that Larry suggests may be portable by helicopters smaller than Chinooks.
The Germans also produced a larger calibre stablemate to the Wespe, the Hummel. Such a vehicle mounting a 155mm gun could be built, but this role can readily be filled by the Soltam Rascal.
Another possible approach to building a lighter 155mm SPH is to simply accept that crew other than the driver cannot ride on the vehicle. This is the approach taken with the French Mk F3 155mm SPH based on the AMX-13 chassis. The rest of the gun crew rode on support vehicles.
Similar could be done with the M113. The AMX-13 FOV also included the AMX-105A and AMX-105B 105mm SPHs, which had overhead protection.
Another useful light 105mm SPH is this design:
Weight of this system was 14 tons. Obviously this vehicle has overhead protection for the crew and could be used in an auxillary direct fire role.
There was a very interesting TV program on artillery the other night that included the 155mm M777 Lightweight Howitzer. I finally got a good look at the design. Very clever! Basically it is like the Russian D-30 but with a baseplate and four short legs instead of the long trails. Wheels are raised for firing and it is towed by the muzzle.
If you can build a 155mm on that carriage for less than 3.75 tons how light could you make a 105mm? What about a 105mm or 120mm tank gun mounted on the same?
There was an animation of a SP version mounted on a LAV-system that was rather simiar to the Russian SP heavy mortars, weapon resting along the top and the baseplate being lowered to the ground to fires to the rear arc.
What the towed version reminds me of is the German Waffentrager- Grille. Adding retractable wheels to the pallet would be prudent.
Proposed for the British Armys LIMAWS(G) requirement is a M777 Portee System based on a Supacat 800 8x6 Truck.
Vehicle and gun can be separated for firing or transport by helicopter. A similar vehicle based on the six-wheeled Supacat 600 had been designed for the LIMAWS(R) requirement and mounted a pod of 6 MLRS rockets or a ATACMS. Both vehicles were intended to provide support for the UKs Rapid Reaction Forces such as 16 Air Assault Brigade and 3 Commando Brigade as well as medium forces.
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Attack, Avoid, Survive: Essential Principles of Self Defence
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