Can I make a request for only one copy of each posting?
'Gene Mechtly' wrote: > How did you determine *range*, Terry, from one point of observation? > Did you use a range finding laser device? No, we did not use laser rangefinders. We used what is called the Mark 2 Eyeball i.e. not much more than a guess. The Mark 1 Eyeball is the untrained version. There are a few techniques taught to soldiers that improve range estimation but they are all fairly primitive. 1. Direct recognition e.g. it looks like a <something> at 1000 metres. This can be practiced. 2. Comparison with map. You have the bearing so you can look at the line on the map. Say the target is visually further than a copse which is slightly left at 10 o'clock. The map puts the copse at 2600 m. So you have a minimum range. With luck you can get a good feature reference that is beyond the target. With a bit of practice, you can use contours as features. 3. Multiples. You know that the distance to the road in front of you is 800 metres. The target is 3 times further and is therefore 3200 m away. 4. Section average. Get a few people to guess the range and take the middle value. It works astonishingly well as a demonstration experiment to get the range. But I didn't find it very practical. 5. In defence: comparison with features close to target on pre-prepared range card (this doesn't eliminate the range estimation task but it puts part of the problem into non-real time). 6. Target size in binoculars. A T72 is about 7 metres long and will measure 7 mils at 1000 metres. This is an intellectually attractive method but I cannot imagine the right combination of circumstances ever appearing. 7. Bracketing. It is common for visual range estimates to be wrong but you can use artillery rounds to get the range. If your first rounds fall short, then add what you think to be double the error. Then halve the difference. > Terry, what are the particulars of a NATO (or UK) Military Compass. It > appears to combine aspects of both the 1918 and Gurley compasses I > have described above. Is there *only* a mil scale, or is there also a > degree scale? There is only a mil scale. Degrees are not used by Nato land forces as far as I know. >What are the least divisions? I believe it is 20 mil. Take a look at the web page in my last email and also this one: https://secure.surveysupply.co.uk/products/prods2/compass/comp-mk4.htm Many British army officers will carry a flat 'Silva' compass for simple navigation and the prismatic compass for artillery work and critical navigation. -- Terry Simpson Human Factors Consultant [EMAIL PROTECTED] www.connected-systems.com Phone: +44 7850 511794
