3D software-3

25.10.2004

Answer or Commentary:

I agree with the last comment however there are a few points. How does one determine the distance that an obstacle is inside the secondary area?

Firstly is the distance to be measured perpendicular to the nominal track or is it perpendicular to the inner edge as suggested by the phrase "full MOC at the inner edge reducing to zero at the outer edge"? The two distances are different and give different MOC values.

In the diagram the blue line is the distance to the obstacle using a line perpendicular to the nominal track, this is the most conservative, and gives the highest MOC. The magenta distance is perpendicular to the inner edge and is less than the blue line giving a lower MOC. Finally the red line is the shortest distance between the inner and outer secondary lines. I think that this line, because it is the shortest distance, must be the slope of any 3d surface.

This final distance (red line) results in the smallest MOC. Which seems to be in contradiction to either the method of measuring the distance perpendicular to the nominal track or the method which is perpendicular to the inner secondary area line.

I.W. (Ed.)