The equation may be written in either of two common formats:

h = horizon (in statute miles)
a = altitude (in feet)

h = sqrt (2*a)

or

h = 1.414 * (sqrt (a))

If we are ballparking instead of surveying, we generally drop it to 1.4.


Jim




"john smith" wrote in message
...
In article .net,
cavelamb himself wrote:


horizon
(in miles) is equal to 1.4 times (sqrt (altitude in feet))


1.4 Jim??

Thought it was 1.17.

Square root of 2 = 1.414