12-inch Siege Howitzer 1916, Part 2 Technical Notes скачать в хорошем качестве

12-inch Siege Howitzer 1916, Part 2 Technical Notes

12-inch Siege Howitzer 1916, Technical details This animation illustrates how the mechanisms of the carriage control recoil, and use the recoil energy to prime a hydraulic reservoir. The 12-inch Howitzer was probably the first British heavy gun to provide hydraulic loading - other contemporary guns relied on manual ramming by teams of gunners. The Howitzer used the Asbury breech, invented by the American Dorsey F Asbury and patented in 1912. This breech used a single lever to unlock, open and close the breech. Having covered the mechanics, the animation gives a simplified example of the corrections that had to be made to take account of the environmental conditions - temperature, atmospheric pressure and wind. Simply setting the range and bearing of a target from a map was not sufficient - it was also necessary to account for any difference of height between the target and the howitzer battery, and the wear of the rifling in individual guns. The Howitzer cartridge consists of a core and (in this example) 5 strap-on cordite bags. The larger the charge, the more wear caused to the rifling. Wear in a barrel results in loss of muzzle velocity. One way to measure this loss would be to fire a around at a known and observable target. The error between the expected and actual impact (registration) could be used to calculate the loss of muzzle velocity. The 12-inch Howitzer carriage limited the elevation that the gun could be fired at: 20 - 65 degrees. With this limitation, a ‘close’ target could be engaged with a minimal charge, while a full charge (charge 6) was needed for maximum range. For a given elevation the range achieved depends on the charge weight. The cartridge charge weights were designed to provide overlapping range spans. Range Tables were created to allow Gunners to calculate the elevation and deflection necessary for each gun in a battery to engage a target. The animation shows range tables from 1942. These are probably more detailed than those available in 1916, but the principles are the same. Despite all the careful calculations, successive shells fired with the same settings are unlikely to land in the same spot. Range tables include an estimate of the area where 50% of shells would land. However the blast from a 750 pound (340 kg) high explosive shell can be extensive. The final part examines three types of shell fuzes. A Direct Action fuze relies on the shell hitting something substantial nose-first. It is a simple, fast acting fuze, but if the shell hits at a shallow angle, it might not get triggered. The Graze fuze is a very sensitive fuze. The detonator pellet is free to move during flight, when it grazes something to check its flight, the fuze is triggered. Howitzers might have to engage a solid fortification or structure where it is desirable for the shell to penetrate the structure before exploding. A common pointed shell would be used. This has a Base Fuze with a powder train that provides a delay after hitting. Base fuzes would normally be fitted at the factory or shell depot. A fuzed shell must be safe to handle, it must not be triggered by the shock of being fired, and only enabled once it has left the barrel and is spinning fast enough open the centrifugal shutters that block the flame path. If you appreciate this animation, please Buy Me Coffee - https://buymeacoffee.com/vbbsmyt or support my channel through Patreon.com: www.patreon.com/vbbsmyt My thanks to the Royal Artillery Museum, Larkhill References: Handbook of the B.L. 12-inch Howitzers, Marks II and IV, 1918 Imperial War Museum Film IWM 218 - ‘With Britain’s Monster Guns in Action’ www.Britishartillery.co.uk - Nigel Evans Handbook for the Ordnance B.L. 12-inch Howitzer, Mk IV on Carriages 12-inch Howitzer Mark II, 1940 Range Tables for B.L. 12-inch Howitzers, 1942 Treatise on Ammunition 1915 Animation made using Cinema 4D, Quicktime and iMovie. Music: Satya Yuga - Jesse Gallagher, Houston Vibes - Unicorn Heads