Israel continues a tradition of developing innovative weapons systems. The latest such idea combines a lightweight 120mm mortars that can fire laser guided shells, with a lightweight hand thrown (to launch) UAV that carries a camera and a laser designator.
The lightweight, low recoil 120mm mortar is called the Spear system. This a 120mm mortar that can be mounted on anything from hummer type military vehicle to a commercial pickup truck. Spear uses an innovative recoil system that reduces the recoil and allows the mortar to be fired from lighter (under six ton) vehicles. The ”soft recoil” system reduces the force of the recoil over 90 percent. The rate of fire is also reduced a bit (from 20 to 16 rounds a minute) but with the use of GPS guided or laser guided shells this is less of a factor.
The UAV is the Skylark 1LE. This is a 7.5 kg (16.5 pound) aircraft with a 1.1 kg (2.4 pound) payload. This is sufficient to carry Israeli designed vidcam, laser designator and communications gear that can work with the American Rover ground terminals (designed to let commanders on the ground see what UAVs are seeing). Max endurance is three hours, max altitude is 4,700 meters (15,000 feet). Max distance from the operator is 40 kilometers.
Several American military commands are evaluation Spear and Skylark, but Israel is also pitching the system to the UN and countries who provide peacekeepers for the UN (and have extra money from the UN to buy special weapons and equipment.) Using the laser guided shell Spear/Skylark can find and hit hostiles even when they are hiding out in residential areas. Spear/Skylark is also inexpensive and lightweight, thus easy for cash-strapped peacekeeping operations to move into an area. Peacekeepers and special operations forces both appreciate a system that employs a lightweight UAV that can fly high enough to avoid ground fire that is backed up by instant precision firepower to destroy a target that will quickly disappear into the background if not attacked promptly.
This is not the first Israeli lightweight 120mm mortar system. Back in 2004 Israeli innovation in this areas led to the use of a 1.6 ton Israeli mortar in the seven ton Supacat HMT (High Mobility Transport). HMT is four wheel cross country vehicle with a capacity for 3.2 tons. The cab was modified to hold the five man mortar crew. The Israeli mortar system was mounted on a computer controlled turntable. The mortar fired regular 120mm shells 8.2 kilometers, or rocket assisted ones 13 kilometers. This was not as far as a 155mm howitzer can reach, but was adequate to reach targets for the smaller (battalion and brigade) units that used 120mm mortars as their artillery. Air power and rockets were available to handle longer range targets.
The breech loading mortar system allowed for rapid fire and the turntable system takes data directly from forward observers and quickly positioned the 120mm tube to put the shells on the target. This mortar system could put shells on the target within minutes of a request. The system fires 20 rounds in two minutes and uses a GPS assisted fire control system to provide accuracy comparable to any other artillery system. The light weight of this system enabled it to be moved by helicopter or V-22 tilt-wing transport. The Spear mortar follows in this tradition, with the same capabilities of earlier lightweight 120mm mortars but now usable in even lighter vehicles.
The 120mm shells are also about half the weight of 155mm ones. This was overcome with a higher rate of fire and the use of several types of cluster bomb shells and, more recently, GPS guided and laser guided. One of these, for example, will destroy most armored vehicles. The laser guided 120mm shell is particularly effective for this because the laser guidance means the shell will hit within a 2-3 meter circle. The GPS guided shells lands within a ten meter circle.
The 120mm mortar is often preferred to 155mm howitzers because the mortar is lighter, faster firing, more mobile and, with the right ammunition, just as destructive as the larger howitzer. For peacekeepers this is ideal because it gives them less destructive but more accurate firepower.