NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Index corr., Octant as dipmeter
From: Trevor Kenchington
Date: 2004 Nov 22, 22:59 -0400
From: Trevor Kenchington
Date: 2004 Nov 22, 22:59 -0400
Alex, As a former artillery man, you will understand the difference between direct and indirect fire. Ship versus ship engagements are (very nearly always) direct fire, which avoids all of the navigational difficulties of indirect bombardments. In exchange, they have their own set of difficulties with both the gun platform and the target changing heading and speed -- slower changes in the target than with anti-aircraft fire but also much lower rates of firing. It is essential to know bearing, range to target and rates of changes in those but the actual position of any of the ships relative to the geoid isn't that important. Rangefinders (radar from about 1940) were vital, as were various mechanical or electro-mechanical analog computers, developed from around 1900 onwards. (I'm not sure when digital electronic computers began to be used for gunnery control but I would guess after 1945.) Navigation was a secondary concern once the shooting started. Aircraft, missiles and the much greater ranges that they introduced did, of course, change things for ship-to-ship conflicts. But it was still shore bombardment of inland targets by indirect fire that posed the greatest navigational challenge for the ship doing the firing. Trevor Kenchington -- Trevor J. Kenchington PhD Gadus@iStar.ca Gadus Associates, Office(902) 889-9250 R.R.#1, Musquodoboit Harbour, Fax (902) 889-9251 Nova Scotia B0J 2L0, CANADA Home (902) 889-3555 Science Serving the Fisheries http://home.istar.ca/~gadus