Combat knife

A combat knife is a multi-purpose knife designed for military use. Several types of combat knives are used by the United Nations Space Command, as well as other human organizations. All UNSC troops are issued a combat knife for field and utility uses, as well as a backup weapon for desperate close-combat situations.

Design details
One version of the UNSC's multi-purpose combat knife has a 20-centimeter (7.9 in) blade made of high carbon steel, an anti-flash, non-reflective titanium carbide coating, edge coated for corrosion resistance and is 43.3 cm long when sheathed. It is also balanced for throwing. The Spartan-IIIs' standard-issue combat knife features a self-sharpening blade made of a hyperdense material. Modern UNSC combat knives are made of strong enough material to pierce a Spartan's helmet, and the hull of a Lich.

Some soldiers in service with the UNSC carry a combat knife of their own design or choice. Major Faison had a very large knife that he kept sheathed at his ankle, with the words "Bug-Hunter" engraved on the blade. Emile-A239 used a large kukri for his weapon of choice. Roland-B210, a member of the SPARTAN-III program's Headhunters division, also used a custom combat knife.

The placement of the combat knife sheath varies depending on the combat uniform and individual loadout, and may be kept, for example, on the shoulder with the handle pointing downward, sideways on the lower back, or on the side of the boot. Some Spartan-IVs keep their knives sheathed in a wrist compartment.

Models
M11 combat knife: A combat knife designed and built for Spartans, and the standard close combat weapon of Spartan Operations. Manufactured by Watershed Division since 2551, the M11 is constructed with hyper-dense metal alloys, making it nearly unbreakable. When wielded by a Spartan operator, the blade can be thrust with force sufficient to penetrate energy shielding or hardened armor. These blades are extraordinarily sharp and retain their edge even after repeated use. The M11 combat knife is 365.8 millimeters in length and weighs 2 kilograms.

History
Knives have been used in battle almost since the dawn of warfare, first as a sharp piece of rock, and then when metal proved effective during a period of time where projectile weapons were not readily available. Even after the invention of the firearm, knives were still used as bayonets for close-quarters-combat and in the event of an enemy's cavalry charge. As more modern times came about during the 21st century, combat knives became almost exclusively used for utility purposes in the field, and were only used as a weapon during desperate situations, simply due to the fact that they were impractical for use during combat in most situations due to firearms and other advanced weaponry.

By the 26th century, the UNSC still use knives in their operations, showing that such an easily accessible and created weapon and tool still runs strong even thousands of years later. Even the Covenant use knives; the Jiralhanae use their own combat knives as well as a multitude of bayonet-like blades. The Sangheili sometimes use curveblades, which inspired the design of the Type-1 energy sword. The blamite-bladed energy cutlass is an analogous weapon used by the Kig-Yar.

Trivia

 * Frederic-104 possesses particular skill with combat knives, and it can be interpreted that he has a liking for their use.
 * When performing an assassination, a second knife spawns out of nowhere. This can be seen in Theater: despite using a knife to assassinate your opponent, it still appears sheathed on your chest.
 * In Halo: Reach, the Security armor permutation for the right shoulder has a kukri on it. However, if a player equips it, there will still be a standard combat knife on your chest and the kukri will remain unused during assassinations.
 * In Halo: Reach, should the sheathed knife be moved by any chest permutations, the player will still sheath the knife in the default position (this is most noticeable with chest pieces such as Tactical/Patrol).
 * In Halo Wars, Sergeant John Forge's combat knife "Lucy" was used to seriously wound Arbiter Ripa 'Moramee, allowing Forge to kill 'Moramee with his own energy sword. In Halo 5: Guardians, Spartan Jameson Locke uses his combat knife to fight and kill Jul 'Mdama the leader of the reformed Covenant.

List of appearances

 * Halo: The Fall of Reach
 * Halo: The Flood
 * Halo: First Strike
 * Halo 2
 * Halo: Ghosts of Onyx
 * Halo 3
 * Halo: The Cole Protocol
 * Halo Wars
 * Halo 3: ODST
 * Halo Legends
 * Homecoming
 * The Package
 * Halo: Evolutions - Essential Tales of the Halo Universe
 * The Mona Lisa
 * Headhunters
 * Halo: Reach
 * Halo: Fall of Reach
 * Invasion


 * Halo 4: Forward Unto Dawn
 * Halo 4
 * Spartan Ops
 * Halo: Escalation
 * Halo 2: Anniversary
 * Terminals
 * Halo: New Blood
 * Halo: Last Light
 * Halo 5: Guardians
 * Halo: Shadow of Intent
 * Halo Mythos
 * Halo: Tales from Slipspace
 * On the Brink
 * Halo: Smoke and Shadow
 * Halo Wars 2
 * Halo: Retribution
 * Halo: Rise of Atriox
 * Halo: Legacy of Onyx
 * Halo: Bad Blood
 * Halo: Official Spartan Field Manual
 * Halo: Outpost Discovery