ΔE 9.1, close: similar, with a visible difference side by side. Deep Khaki Drill is a little darker, warmer than A-21m Light Yellowish Brown.
Usually, if you are not matching paint already on the model. Close match (ΔE 9). Deep Khaki Drill is a little darker, warmer than A-21m Light Yellowish Brown.
The same difference applies the other way round: A-21m Light Yellowish Brown is a little lighter, cooler.
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 A-21m Light Yellowish Brown on the colour wheel See Deep Khaki Drill on the colour wheel
All matches: A-21m Light Yellowish Brown equivalents · Deep Khaki Drill equivalents