Norwegian munition manufacturer Nammo revealed at Eurosatory that it is developing a ramjet-assisted, INS/GPS-guided round for 155 mm L52 artillery pieces that will extend the range of precision fires out to 100 km and beyond.
Although it would sound like a wonderful idea, this is the usual over expensive, over engineered ideas looking for a market.
At 100kms the target you would want to hit will a large one like airfield or factories or storage. How many of these rounds can you fire? Just a normal guided shell is uber expensive. This one will more expensive than those. And all for a 45 kg warhead?
You are are better off using air launched glide weapon with a large warhead. Artillery are meant to cheap and something you can fire in thousands and constantly..
Long range precision fire is one of the upcoming strategic priorities of the US army
among others. There are a variety of such equipment
with varying ranges, from missiles,to integrated shells to screw on kits on regular shells/rockets.
Precision fire can often be effectively cheap because it allows for support near friendlies, reduced collateral damage and reduced shots/time/ammo to take out the objective (which increases survivability eg against counter battery fire) . ie The 100 km target need not be a large one !. There are limitations (eg suppression,area fire etc). It's not immune to being too expensive/wrong requirements
, small lots. You already have dedicated ballistic missile/rocket artillery. The hope is that providing greater flexibility with less dedicated units will help. But ramjet guided shells
seem to be a little ambitious, even if a south korean firm has also announced similar concepts
; it might pay to be careful
Air launched brings in a number of other complications (air co-ordination, sortie rate, air supremacy, limited airframes, reduced conditions at take-off. etc). It can have a role,too, but there's no single carte blanche panacea.