I imagine fuses had to be set for altitude( except for later U.S. proximity ). And for distance. Did wind/rain etc come into computing firing? How did they do it before computers, slide rulers? When was first mechanized range finder used (WW1?), and when were they capable of being incorporated onto the gun itself? Seem to recall the enormous ones used for Japanese ships from a link here. And then a small unit on a British field arty piece....Could look all this up, but where's the fun in that?
This is one of the early gun director computers although there were some simple ones apparently in the 20s and 30s, best I can establish there were none used in WW1 outside of ships Kerrison Predictor - Wikipedia, the free encyclopedia edit - apparently the Vickers predictor was the earliest useful land based one from 1928; http://www.militariarg.com/signal-corps--other-technical-equipment.html (about 1/3 of the way down) http://www.wpafilmlibrary.com/detai...get/47f1adca-ac1c-102b-b605-0030482f0128.html This might interest you; http://sydney.edu.au/engineering/it/research/tr/tr223.pdf - rangefinders harder to answer - as range was judged back to at least napoleonic time by assorted mechanical and optical devices, the sextant being one of the first accurate ones, but the technology was earlier than that. Binocular rangefinders were used during WW1,The Museum of Technology, the Great War and WWII" probably not much before that - found a 1908 model. Hope it helps
I spent a little time as a mortarman (I was a school trained machinegunner but my first unit was short of mortarmen so I spent @6 months as a mortarman, OJT'd) and also some time after I came off active duty in a reserve artillery battery, same basic priciples. Yes before computers, firing data was calculated with data charts and slide rules. Atmospheric conditions are/were factored in, I used to take ballistic met messages for use in computing artillery firing solutions.
Bookmarked. The bits I saw were totally interesting. Another angle I'd never really considered. Artillery is it's own science. Thanks for your efforts SR. You banged that out in minutes and it's chock full of vitamins
Some fascinating details of WWII era naval fire control computers: http://www.hnsa.org/doc/op1140/index.htm (Slow download but worth the wait) http://www.hnsa.org/doc/op1140/op1140-2.pdf - Mechanical computer components More manuals: Navy Documents Edit: This was the manual I was really after - a fascinating and fun read: http://www.hnsa.org/doc/firecontrol/index.htm
Poppy's initial post implies interest in AA artillery specifically. On that point I wish to point out that before the advent of the VT fuse, the universal practice was to fuse AA shells based on time, not altitude. Before radar this was done typically with some form of ranging (binocular) theodolite, which gave a "line of sight" range and an angle above the horizon. A quick look to the trig tables yielded a calculated altitude. Consulting a ballistics table for the gun and the shell yielded a time in flight for a shell fired at such and such an angle to reach that altitude. If the table said 2.2 seconds, that how you set the fuse. The problem is the enemy planes are moving all the while, so the vertical angle and the "line of sight" distance are changing all the while. Calculations and more calculations! The Germans attempted to solve this with a barometrically fused 128mm shell -- if the enemy is at 7000 meters, that how you set your fuses. Just point and shoot. Fortunately for the Allies, this project never yielded anything useful. The VT (variable time) fuse wasn't anything of the sort. I suppose the name was a form of disinformation. The VT system used a small radar transceiver to detect proximity. There was also a backup time fuse to make sure the shell detonated at or near the top of its ballistic arc so that there was no danger of missed shots falling on friendlies. (BTW A lot of the damage done to Honolulu on 7 December 1941, initially blamed on savage Japs bombing helpless civies, was caused by AAA misses). One problem with the VT fuse was its size. It was too big to use with the 90mm M3 AA gun, so it's first use was confined to the naval 5/38 dual-purpose mounts.
Can't find a source right now, but IIRC one of the reasons they mounted more AA artillery on vehicles in early WW1 than field mountings was because they would try and drive at as high speed as they could, hopefully on a road roughly parallel to the aircraft's flight path - this was just for balloons and similar I'm fairly sure, although they may have used the technique with aircraft as well - this left them not having to calculate as much significant other than distance/time to target and set the time fuzes as Cpl P said. They apparently had more success with this method than you might think!
Basically depth charge fuses were manually settable barometric/pressure fuses, although I guess they may have used time fuses and other methods too - I suspect the problems with a high velocity round and a pressure fuse are the natural high pressures induced while firing and in flight, separate from the barometric pressure, and I guess they overcame at least some of these problems, but not all. Not found anything, but i guess some air-dropped weapons designed for airburst may have been Barometrically fused, although there weren't many of those in ww2, and the problems of barometric altitude measurement are many.
Seem to recall US dropping depth charges from fighters on land troops during Guadalcanal with devastating results. Any truth to that? Any other instances of depth charges being used for things other than depth charging? I guess in a pinch, use what you got.
Certainly the Germans dropped naval mines over land targets quite regularly during the blitz. See no reason why not a depth charge if you have a lot more in stock than you think you need - they have a fairly short shelf life, so by that period in the war they may have found less need than expected for ASW? probably fitted with a different or extra fuse. I'm sure unwanted depth charges were used for static demolitions from time to time, and i vaguely remember stories of them being buried as large landmines, probably remote detonated, but doubt if was common.
Do you mean the spikey kind of ship mine? That would be hard to put on a hard-point or center line. How would they drop a mine? Depth charge could be carried in a torpedo bay I'd imagine.
