ΔE 6.2, close: similar, with a visible difference side by side. Aircraft Gray Green BS283 is more saturated than Dark Imperial Khaki.
Usually, if you are not matching paint already on the model. Close match (ΔE 6). Aircraft Gray Green BS283 is more saturated than Dark Imperial Khaki.
The same difference applies the other way round: Dark Imperial Khaki is more muted.
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 Dark Imperial Khaki on the colour wheel See Aircraft Gray Green BS283 on the colour wheel
All matches: Dark Imperial Khaki equivalents · Aircraft Gray Green BS283 equivalents