The IDF standard M3A1 Mk-C type mounted a 81mm
mortar on a rigid baseplate, which, during the first Arab-Israeli wars
became the main tactical support weapon in tank and armoured infantry
companies and battalions. Combat proven by
insufficient firepower, it was followed by the Mk-D heavy mortar
carrier, mounting the Soltam 120mm mortar. Initial firing tests on an
AMX-13 chassis failed due to the excessive recoil (120 ton local
pressure!) but an ad-hoc quite simple solution produced the answer.
Instead of trying to absorb the recoil forces elastically, the Israeli
technicians mounted the mortar base to the halftrack mass permanently,
thus achieving an overall absorbtion of the recoil blast by the carrier
spring mechanism itself. The Mk-D 120mm mobile mortar became a key
element in IDF combat support for many years, until more technically
advanced systems were locally developed by Soltam.