I'm aware that automatic fuze setting for AA shells was introduced during WW2 (Machine Fuze Setting No11), so a few technical questions, if someone could assist, please: 1) I am unclear as to how this worked - was the fuze set before or after loading, and how? 2) Were all fuzes able to be set automatically, e.g. 199? 3) Which theatres of war were supplied with them, e.g. Italy? I'm aware that gun crews on the MkIII 3.7" Vickers denote one member as a 'Fuze Setter' - was this still a manual task? 4) What was the process of setting the fuze before automation? Was this literally a matter, for example, of turning the timing ring on a 199, and then switching it from 'safe' when loading it into the tray? Thanks in advance!
Machine Fuse Setting No11 was part of the power operated, remote controlled gun control system. The fully developed system used the US Radar NoIII Mk5 and predictor No10. These relayed all necessary information direct to the guns and automatically aimed, laid, set fuse, loaded a fired the gun. The fuse setting machine was fitted to the automatic loading tray. A shell was dropped into the tray, the fuse setter fitted over the fuse ring and set it to the correct time and the shell was power loaded and fired. The great advantage of this was that the time taken to set the fuse by hand, load the shell into the breech and then fire it used to vary between crews and over time as the loaders tired. The automatic system was always constant and thus the time for loading could be calculated and greater accuracy achieved. I dont think the system could be used on mobile guns. Mike
Mike, thanks for that, very helpful. The reason for my question 3 is that Routledge (p77) says that "a version was added to the mobile 3.7" mounting", and wondered whether these had found there way to Italy. I think the No11 was introduced in 1942.
I see tucked away in Hoggs 'Artillery of WWII' there is such a gun as you describe. This was a standard mobile 3.7" AA gun fitted with a loading tray and No11 fuze setter. Introduced in 1943 it predated the advanced system described above. It was also fitted to static mountings. No mention of Italy but this is quite likely, especially when more advance systems were introduced in the UK. Another byway to explore. Mike
Would the Machine Fuse Setting No11 be the "PF" referred to in this extract from 76 AA Brigade's war diary? This is from the Normandy period. I know that the GOR was the Ground Operations Room, and LW(V) was the AA No.4 Mk.III radar set. It may have been the case that PF was the brigade's own term, and possibly it stood for predictor - fuse setter. I certainly haven't seen the term PF used in any technical AA artillery documents.
