Stallie!
Here is a worked example to find the circumcentre Alice Springs, Adelaide, Brisbane. I have left a case of Bundaberg there and a Toohey's or two. I used compsys21 dads and routines <inverse> and <bearing-bearing>. the former does distances and azimuths; the latter does intersections; check the answer with <inverse>.
To find the circumcentre of the spherical triangle YBAS-YPAD-YBBN
B = YBAS = S23* 48’ 24” E133* 54’ 08”
A = YPAD = S34* 56’ 42” E138* 31’ 50”
C = YBBN = S27* 23’ 03” E153* 07’ 03”
Mc = S29* 23’ 53.457” E136* 05’ 23.767” Az McA = 160.123*
Az McO = 070.123*
Mb = S31* 22’ 22.400” E146* 06’ 56.332” Az MbC= 058.718*
Az MbO = 328.718*
Ma = S25* 54’ 50.523” E143* 21’ 55.978” Az MaB = 281.692*
Az MaO = 191.692*
Intersection McO-MbO = S26* 55’ 55.076” E143* 07’ 50.089”
Intersection MbO-MaO = S26*55’ 54.796” E143* 07’ 49.909”
Intersection MaO-McO = S26* 55’ 55.184” E143* 07’ 49.189”
Assumed circumcentre is S26* 55’ 55.019” E143* 07’ 49.729”
Distance BO = 535.024nm
Distance AO = 535.025nm
Distance CO = 535.028nm
Therefore the circumcentre has been found.
