ΔE 13.7, fair: the same colour family, but not a straight swap. Tan (USAF) is a little darker, warmer than Krieg Khaki.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 14). Tan (USAF) is a little darker, warmer than Krieg Khaki.
The same difference applies the other way round: Krieg Khaki 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 Krieg Khaki on the colour wheel See Tan (USAF) on the colour wheel
All matches: Krieg Khaki equivalents · Tan (USAF) equivalents