ΔE 12.6, fair: the same colour family, but not a straight swap. Green Sky is noticeably lighter, more muted than RLM 82 Light Green.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 13). Green Sky is noticeably lighter, more muted than RLM 82 Light Green.
The same difference applies the other way round: RLM 82 Light Green is noticeably darker, 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 RLM 82 Light Green on the colour wheel See Green Sky on the colour wheel
All matches: RLM 82 Light Green equivalents · Green Sky equivalents