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This is Q.  I’ll try and produce a decent diagram next time.  It’s still on the back of an envelope at the moment.  Once you know which quadrant your in, you could also find Q using geometry.  Now all you have to do is decide whether to add or subtract it from Hs.  "Why not act as follows?" Probably because I’m completely wrong.  I await comments.  DaveP

I thought I’d better check my graphical solutions to the 1998 Q problem before making any more bold statements about it.  In doing so I found a much simpler mathematical solution.  As I said in my earlier post today, one of the problems in commenting on posts is that often insufficient information is given as to what the solution has to achieve.  Do we need Q to 0.1’ accuracy as proffered by the Nautical Almanac or will 1’ as proffered by aeronautical tables do.  As a rule of thumb sort of nav, I find Polaris Tables in the Nautical Almanac with a₁ and a₂ included a bit complicated, so let’s stick with the aeronautical Q Table in AP3270 Vol 1 (US Pub 249?).  The only set I had available was for the 1980 epoch which were calculated for an SHA of 326° 52’ or 326.87° and a declination of N89° 10.5’.  Most scientific calculators can cope with degrees over 90 and 360 using the “all silly tabby cats” rule, so the simple formula is Q = minus 49.5 x Cos (LHA Aries + 326.87) minutes of arc to be applied to the corrected sextant altitude.  Using this gave me Q values within 1’ of the values in AP3270 / Pub249

On a Casio fx992s the fingering was:  [Cos] [LHA Aries + 326.87] [=] [x] [49.5] [+/-]

In EXEL this was =-49.5*COS(RADIANS(xy+326.87)) where xy is the cell into which you’ve placed LHA Aries.  Keep hitting reduce decimals until you’re down to an integer.
For 22Jun1998 you should use SHA Polaris= 323.158° Declination Polaris =  89° 13.9'

 So the formulas would read  Casio Q is [Cos] [LHA Aries + 323.158] [=] [x] [46.1] [+/-]

 EXEL:   Q is =-46.1*COS(RADIANS(xy+323.158)) Please check before trusting!

 DaveP