ΔE 10.6, fair: the same colour family, but not a straight swap. Sand Yellow RLM79 is a little lighter, more saturated, cooler than Brown.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 11). Sand Yellow RLM79 is a little lighter, more saturated, cooler than Brown.
The same difference applies the other way round: Brown is a little darker, more muted, warmer.
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 Brown on the colour wheel See Sand Yellow RLM79 on the colour wheel
All matches: Brown equivalents · Sand Yellow RLM79 equivalents