Editing PIAT (section)

==Design==
[[File:Kinematics of the PIAT Anti-Tank weapon CC BY-SA 4.0 by Grasyl.svg|thumb|In firing, the pin moves forward into the round, the round is fired pushing the rod back against the spring and cocking it again.]]
The PIAT was {{convert|39|in|m}} long and weighed {{convert|32|lb|kg}}, with an effective direct fire range of approximately {{convert|115|yd|m|0}} and a maximum indirect fire range of {{convert|350|yd|m}}.<ref name="War Office Manual"/> It could be carried and operated by one man,<ref name="War Office Manual"/> but was usually assigned to a two-man team,<ref name="Bishop, p. 211">Bishop, p. 211</ref> the second man acting as an ammunition carrier and loader. The body of the PIAT launcher was a tube constructed out of thin sheets of steel, containing the spigot mechanism, trigger mechanism and firing spring. At the front of the launcher was a small trough in which the bomb was placed, and the movable spigot ran along the axis of the launcher and into the trough.<ref name=Weeks/> Padding for the user's shoulder was fitted to the other end of the launcher, and rudimentary [[Peep sight|aperture sights]] were fitted on top for aiming; the bombs launched by the PIAT possessed hollow tubular tails, into which a small propellant cartridge was inserted, and shaped charge warheads.<ref name=Weeks/>

Conventional spigot mortar designs have a fixed spigot rod, for example the [[Blacker Bombard]]. The moving spigot rod in the PIAT design was unusual, and served to help reduce recoil sufficiently to make it a viable shoulder fired weapon.<ref name="War Office Manual"/>

The PIAT was a little lighter by about {{convert|1|kg|lboz|abbr=on}} and about {{convert|0.6|m|ft|abbr=on}} shorter than its predecessor, the [[Boys anti-tank rifle]], although it was heavier than the {{convert|18|lb|abbr=on}} [[bazooka]].

[[File:A PIAT (Projectile Infantry Anti-Tank) in action at a firing range in Tunisia, 19 February 1943. NA756.jpg|thumb|left|A PIAT team at a firing range in Tunisia, 19 February 1943; part of a demonstration team. Crew has a cardboard three-round ammunition case]]
To prepare the weapon for firing the spigot mechanism, which was operated by a large spring, had to be cocked, and to do this was a difficult and awkward process. The user had to first place the PIAT on its [[Stock (firearm)|butt]], then step on both sides of the shoulder padding (a la [[Pogo stick]]) and quarter-turn the weapon to unlock the body and simultaneously lock the spigot rod to the butt; the user would then have to bend over and pull the body of the weapon upwards, thereby pulling the spring back until it attached to the trigger sear and cocking the weapon. Once this was achieved, the body was then lowered and quarter-turned to reattach it to the rest of the weapon, and the PIAT could then be fired.<ref name="Hogg45"/> Users of a small stature often found the cocking sequence challenging, as they did not have the sufficient height required to pull the body up far enough to cock the weapon; it was also difficult to do when lying in a [[prone position]], as was often the case when using the weapon in action.<ref>Hogg, pp. 45–46</ref>

Note, however, that troops were trained to cock the PIAT before expected use, and "in action the projector will always be carried cocked" (but unloaded).<ref name="War Office Manual"/> Unless a stoppage occurred, it would not normally be necessary to manually re-cock the weapon in action.

When the trigger was pulled, the spring pushed the spigot rod (which has a fixed firing pin on the end) forwards into the bomb, which aligned the bomb, ignited the propellant cartridge in the bomb and launched it along the rod and into the air. The recoil caused by the detonation of the propellant blew the spigot rod backwards onto the spring, similar to that of a [[Blowback (firearms)|blowback operation]]; this reduced the shock of recoil and automatically cocked the weapon for subsequent shots, eliminating the need to manually re-cock.<ref name=Weeks/><ref name="Hogg45">Hogg, p. 45</ref>
[[File:Australian PIAT team Balikpapan.jpg|thumb|An Australian PIAT team during the [[Battle of Balikpapan (1945)|Battle of Balikpapan]], 1945]]
Tactical training emphasized that it was best used with surprise and concealment on the side of the PIAT team, and where possible enemy armoured vehicles should be engaged from the flank or rear.<ref name="Bull">Bull, p. 42</ref> Due to the short engagement distances and the power of the bomb, the crew could be in the bomb blast zone so hard cover was desirable; on open training grounds this might be a [[slit trench]].<ref name="War Office Manual"/> The PIAT was often also used in combat to knock out enemy positions located in houses and bunkers.<ref name="Bull"/> It was possible to use the PIAT as an ad-hoc crude [[Mortar (weapon)|mortar]] by placing the shoulder pad of the weapon on the ground and supporting it.

Despite the difficulties in cocking and firing the weapon, it did have several advantages. The Spigot mortar design allowed a large calibre powerful shaped charge bomb<ref name=Weeks/> giving greatly increased penetration power over the previous anti-tank rifles, allowing it to remain effective for the rest of the war; its construction was relatively simple and robust without a conventional barrel; there was no back-blast (unlike the contemporary American [[bazooka]]) that might endanger friendly troops and give the user's position away, this also meant that the PIAT could be used in confined spaces as in urban warfare; compared to the previous anti-tank rifles the muzzle blast was minimal, also a potential concealment issue. However, the weapon did have drawbacks. It was very heavy and bulky, which meant that it was often unpopular with infantry required to carry it.<ref name="Bishop, p. 211"/> There were also problems with early ammunition reliability and accuracy. Although the PIAT was theoretically able to penetrate approximately {{convert|100|mm|in|0}} of armour, field experience during the [[Allied invasion of Sicily]], which was substantiated by trials conducted during 1944, demonstrated that this capability was often nullified by problems of accuracy and round reliability. During these trials, a skilled user was unable to hit a target more than 60% of the time at {{convert|100|yd|m|-1}}, and faulty fuses meant that only 75% of the bombs fired detonated on-target.<ref name="French"/>