A few questions regarding Range Finding

[BasilY]

I have done 100% on GWX for some time now, and was pretty good with the target data inputs. But some questions remained the practicality the SH3 method in real world combat situation.

1. In SH3/GWX, your WO will give you a good range to target while on the surface (within 100 meters). Did he use optical range finders? (like those used in Surveying?) Is it installed on the UZO?

2. When you are observing the target using the periscope, SH3 advise the use of pause when measuring the height of the target from water line (and that's on a wide screen monitor most of us have). How will a real world captain, observing a moving target thru a small periscope viewer on a tossing boat, measure the height of a target with any degree of acuracy?

2a. If the method (as praticed in SH3 100%) was used by real world captains, how exactly did they do it?

3. If not, do they use optical range findings adopted for use in periscopes? And this wil make sense too. If the boat is stationary, (mine is, while observing) two observations, 3 minutes apart, each with heading and range with define a triangle, giving you the length of the third side (thereby the speed of your target and the AOB as well)

So really, how do real uboat skippers do it? Your inputs are appreciated.

[GoldenRivet]

i believe the process involved counting the vertical tick marks on the UZO/Scope cross hairs - each representing say - a degree. then comparing that to the mast height of the target as indicated in the recognition manual. given a specific mathematical formula of a triangle given known variables you could estimate the range failry accurately. you could do the math on paper... but i would say - like in aviation - a lot of the mathematics was done via "whiz wheel" / "slide rule" for a quick estimate.

but - even with good math there would be a margin of error

range however as far as im aware was only needed in a solution to determine the running time to impact.

otherwise i dont think it was so important as speed and AOB

Edit... from what i have read and been told, these U-Boats had a range calculating stadimeter built in. all you had to do was set one image atop the other and read the range estimate from a dial.

thats it - its expected to have a margin of error... the only thing range was used for was determining how long it would take the torp to get to the target.

crews understood there was error involved.

when they estimated 40 seconds to target they knew it might actually be 47 seconds or 35 seconds etc