NavList:

John wrote:  I think I probably misunderstood Andres' problem, but I was commenting on a fix by horizontal angles, rather than by intersecting compass bearings.  Horizontal angle fixes are usually associated with the use of a sextant, but a pelorus, or a compass with a constant, unknown error will also do the job.  Of course, a satisfactory choice of objects for a good angle of cut between the circular LOPs is a good idea

 

We used to do similar to score radar PPI photos.  Photograph the screen.  Place tracing paper over the print.  Draw lines from the centre of the print though radar significant places which also appear on the 1:50,000 map.  Move the tracing paper around over the 1:50,000 map (actually it was a 1:63,000 map in those days) to get best fit of lines over points and that’s where you were when you took the radar photograph  +/-  ¼ mile or so. We never measured bearings using that method.  DaveP (too many Daves!)