The Covenant's use of energy shielding has always been their greatest advantage. Without it, the effectiveness of their directed energy weapons could perhaps be countered to the extent that ground forces would be able to make an effective resistance. As it is, any equipment or vehicle that features shields are three times harder to kill than their unshielded counterparts, and the widespread use of shields has allowed the Covenant unprecedented defensive abilities.
The SAM 41 "Switchblade" was an attempt to negate this effect. In most regards, the Switchblade was a standard surface-to-air guided missile, compatible with the M41, M19 and M19-B Shoulder-Operated Man Portable Rocket Launchers, featuring a High-Explosive warhead. The rocket would acquire the target using an advanced TADS, tracking the target until impact. Normal rockets would usually either bounce off or detonate on the energy shield, leaving negligible damage in their wake. The Switchblade circumvented this entirely by installing a miniature electromagnetic pulse generator within the missile itself - not effective enough to lower the shields entirely, but sufficient to open a gap through which the Switchblade could penetrate, detonating against the exposed hull. Early models relied on a timer, activating the EMP seconds before impact, time enough to leave a gap in the shields. With nothing between the missile and the target, the Switchblade was able to penetrate targets with a nearly 70% success rate - though less than ideal in combat against a xenophobic hegemony of genocidal religious zealots, it was enough to raise UNSC kill ratios against enemy aircraft by 80%, a staggering improvement over past records. At the time, the use of EMP weapons against Covenant energy shields was an entirely new concept and scarcely used, but it would be a tactic adopted rapidly in the coming years.
Introduced in 2539, the Switchblade would soon become a staple of the UNSC Army and Marine Corps arsenals, proving invaluable against Covenant fighters and dropships. It would also prove to be the basis of the AShM 441 "Anubis", a ship-to-ship missile that took the concept of using EMP in combat to a whole new extreme. Eventually, the Switchblade would halt production and be replaced by the more advanced Anaconda SAM in 2548, after seeing action in forty two theatres of combat in only nine years of service. During its time, the Switchblade was mass-manufactured in unprecedented numbers by the assembly lines of Misriah Armouries, and was adopted by virtually every ground force branch, helped by its compatability with virtually all UNSC launchers. When production ended, the Switchblade was still being used en masse by many ground units, and was often preferred over its successor by some units. Even after it was phased out of service, Switchblades were common in the military black market, often used by militia groups unofficially endorsed by ONI.
- "I remember back when the war was only just starting, when I was in an Army anti-air artillery battery. We rolled up, expecting the enemy to go down in a few minutes after our barrage of rockets - the damned things just kept coming. When the Switchblades came out, I don't mind telling you our kill-to-death ratio went up 80%."
- "The Switchblade doesn't look much different to a normal missile. There's a ring at the base of its' midsection, though, where the EMP is generated. It can punch a hole in the shields of a Seraph - not much good if the warhead fails to go off, though. Some of those Misriah assembly lines do very sloppy work."
- "There's still combat units using the Switchblade. They made a LOT of these things, and even after they stopped making them they're still in plentiful supply. Popular too. The Anaconda may be faster and more accurate, but it just doesn't pack as much "oomph" into the blast."