--
The primary differentiation between the systems involves the way in which each of them handles kinetic energy rounds (or kinetic energy penetrators). The Trophy system handles threats with warheads, while the Iron Fist system can also handle kinetic energy rounds. A kinetic energy (KE) round is a long tungsten rod, shaped like an arrow, with a sharp point and stabilizing fins. To fit the caliber of the cannon firing it, the round is surrounded by a plastic shell called a Sabot, which separates from the round after it leaves the cannon. IMI, Rafael and the IDF Ordnance Corps were world pioneers in the development of such armor-piercing rounds, and the first KE round that entered service in IDF was known as Lituf (APFSDS - Armor-Piercing Fin-Stabilized Discarding Sabot). KE rounds of this type were used by the IDF 421st Brigade, the first IDF armored brigade that crossed the Suez Canal in the Yom-Kippur War of 1973, against the Egyptian armored formations.
“It is a long, thin rod that leaves the barrel at a speed of 1,600 meters per second. Its depth of penetration equals the length of the rod. How do you stop it? You shift it by an explosion,” explains Peretz. “The idea is to tilt it off course, and then it would not hit the target with its sharp point but with its body, thereby losing energy. The ideal is to rotate it by 90 degrees, but that is very difficult to accomplish. In effect, tilting the trajectory of the round by 7 degrees is enough to cause it to lose 80% of its energy and penetrate 30 to 40 mm of armor maximum. It will penetrate a light APC even in this case, reaching from one side to the other, but it would not damage a tank. Such a round costs several thousands of dollars and it is very cheap compared to other round/missile types.”
--