NavList:

Sam.  It’s difficult to analyse what might be causing your problem without knowing what the two longitudes are.  Please post these.  If the start point is the position of the observer (Z on a PZX triangle) and the finish point is the position of the body (X on the PZX triangle) and LHA is +10 minutes of arc. Then by the definition of LHA, the finish point must be west of the start and the bearing of the finish from the start is 356 degrees or -4 degrees.  If you want it to be 004 degrees then the finish must be east of the start, and the LHA is more like 359degrees 50 minutes.  Until you post the longitudes, it’s hard to go much further.  Formulas are rarely wrong, but you have to understand where the triangle you're trying to solve lies on the surface of the Earth.  Unless you've got a brain the size of an elephant, for that you need a diagram. Dave