ΔE 7.5, close: similar, with a visible difference side by side. Dark Sand is a little darker, more muted than Flak Gun Yellow.
✓ Two Thin Coats comparison chart lists these two as equivalents.
Usually, if you are not matching paint already on the model. Close match (ΔE 7). Dark Sand is a little darker, more muted than Flak Gun Yellow.
The same difference applies the other way round: Flak Gun Yellow is a little lighter, more saturated.
ΔE is the colour difference between our two swatch estimates: under about 6 is close, over about 15 is loose. Real paints also differ in finish, coverage and how they thin, so test before you commit.
See Flak Gun Yellow on the colour wheel See Dark Sand on the colour wheel
All matches: Flak Gun Yellow equivalents · Dark Sand equivalents