Field Manual: Grenade

Data Canister 0508c; X-COM Archives
Small Arms/Ammunition
M41 Grenade Family

The standard-issue hand grenades used by X-COM throughout the First Alien war were all members of the M41 FOFUS group. These represented a departure from contemporary grenade design, based on the experiences of military forces in small-scale peacekeeping and regional conflicts during the late 20th century.

Design conception took place in the early 1990s, following the end of the Cold War and bearing in mind the new military paradigm of multirole equipment. Existing designs, such as the L2A2 and M29A2 antipersonnel fragmentation grenades, had been found to suffer from significant operational inadequacies due to the design of the fragmentation component. Reports from the Falkland Islands conflict of 1982 highlighted this end-user dissatisfaction, where the small, high-velocity fragments produced by the notched-wire filler were often absorbed by the soft peat terrain. Similar issues were reported again during Desert Storm, where soft sand caused identical failings.

With this in mind, the design team looked to the grenades of World War II - the No.36 Mills Bomb, and the MkIIA1, whose most significant distinguishing feature with respect to modern thrown explosives was a heavy cast-iron fragmentation casing, which produced larger, heavier fragments with better penetration qualities. With this in mind, the team set out to replicate the design using modern materials. In a number of trials, sponsored by government defence procurement agencies and private security concerns, a 5mm aluminium casing was found to replicate the fragmentation properties and pattern of the classic MkIIA1 'pineapple', while retaining a weight similiar to the modern designs.

The revolutionary component, and the one from with the series takes it's name, was the Full-Option FUsing System. Previously, the detonation delay of the grenade was determined by the fuse charge. While a number of fuses - 1s, 3s, 5s and 10s being the most common - were available, flexibility was limited by the necessity to screw the fuse into the body before use - a simple but delicate operation rarely performed under fire. This led to ineffective grenade use, where overly long fuses were used for maximum flexibility, but at the same time providing opportunity for enemy soldiers to escape the blast, or in some recorded instances, to throw the grenade back. Attempts in the field to work around the problem, by 'cooking' grenades (i.e., allowing them to arm and start counting down before throwing them) were partially successful, but often resulted in injury to the thrower.

To counter these problems, a universal fuse was created. Using a simple, electromechanical timer and detonator, the user was able to select a suitable delay at the time of the throw. A simple twist cap both broke the insulating safety seal and rotated the detonator contacts away from each other by the correct amount. The ruggedised production fuses were accurate to at least 1s in 30s, and frequently surpassed this. Although initially designed to fit only into the M41 fragmentation body, a number of adapters were produced to allow compatibility with other explosives, notably the Mk.4 WP/Smoke grenade. It's simplicity and robustness also led to a standalone version suitable for use with demolition charges. The fusing system underwent further development after entering X-COM service, ultimately being incorporated in an alien elerium charge as a human-usable alien grenade, replacing the barely-understood psychotronic mechanism originally installed.

The fusing system proved so reliable and successful that it was used as the basis for the motion-sensing thrown antipersonnel mine commonly known as the prox grenade. In this variant, the twist-timer was replaced by a simple on/off switch for a crude vibration-based motion sensor. Used with both the M41 and M29 grenade bodies during the First Alien War, it was found to be extremely useful in the fast-moving small-unit environment. A final production version, introduced in 2005, incorporated a new sensing head based on X-COM research, and a remote-safe disarming system.

(See also Grenade, Proximity Grenade, Smoke Grenade; also cross-ref Alien Grenade)

- usmarox in StrategyCore Data Canister, pasted by JellyfishGreen