NavList:

Geoffrey Kolbe wrote: Surely the whole point about a sun compass is that you keep adjusting it for local time...?

Geoffrey
To add a bit more.  The way I read the original question was "Could you keep the Sun in the same position relative to the aircraft", which of course you can’t.  The Sun’s relative bearing would gradually move forwards or backwards depending upon which direction you approached your destination from. 

Yes, if you increased the Sun compass azimuth reading by one degree every four minutes making a further allowance for your rate of change in longitude, you would maintain the same heading.  However, at a time when you need maximum time for looking ahead for your destination, wouldn’t it be easier to follow that heading on your steering compass, and directional gyro.  Of course, if a Sun compass were all you had, you’d have to keep tweaking the azimuth setting. 

A Mars Bar for the first person to come up with a formula for the time between one-degree tweaks bringing in latitude, groundspeed and track.  Two Mars Bars for three nomograms to achieve the same answer. DaveP