[Proj] Scale factor for Transverse Mercator

Gerald I. Evenden geraldi.evenden at gmail.com
Wed Sep 10 15:37:26 EDT 2008

On Wednesday 10 September 2008 3:17:50 pm Clifford J Mugnier wrote:
> The State Plane Coordinate Systems were 
> The Scale Factor at a Point maximum of 
> 1:2,500 at the Central Meridian was considered OK for Fire Control because
> for this application, the 6° Zones were limited in longitudinal extent
> because of the convergence angle between Grid North and Geodetic North -
> soldiers don't really care that much about the difference between Grid
> Distance and Geodetic Distance ... the blast radius of a 155mm Howitzer
> shell takes care of that little "problem."

Under the same logic, I could never understand the reason for fuzzing the GPS 
signals because what difference does a few meters mean with the blast radius 
of an H-bomb?

The wonders of the military mind.

If one is laying in air burst of with 155 a little fuzz will not make much 
difference because you are probably doing a carpet barrage anyway.  But if 
you are trying to knock out just one house in a city block (like they do with 
the smart bombs) then ... .  Curious about the electronics in some of the 
newer artillery pieces.  New command and control is something else from what 
little I've seen and heard.

The whole religious complexion of the modern world is due
to the absence from Jerusalem of a lunatic asylum.
-- Havelock Ellis (1859-1939) British psychologist

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