NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: David Pike
Date: 2022 Mar 8, 13:56 -0800
Tony Oz you said: my point is that the tan (or cotan) table is not enough, it is more tricky on an inclined surrface.
Even if you know that your pace is 47 centimeters on a 12° slope (upwards) and the shadow is 21,5 paces long, - you will have to solve a more complicated problem than the multiplication of two numbers (to get the height of an object casting that shadow).
Tony
I don’t believe I mentioned a tan table. When you get to 78, you realise that navigation is nothing if you don't make it fun take advantage of every opportunity offered. In this case a sharp shadow and a Sun's altitude of 30°.
I approached the problem by saying Perp=Base x Tan altitude. However, altitude ≈ 30°, and from pilot nav, Tan30=1/ √3 ≈ 0.6. Therefore, height of tower ≈ (34/66) x 100 x 0.6 ≈ 34/1.1 ≈ 31m. It’s just a way of entertaining those unwise enough to go walking with you. DaveP
