ΔE 11.4, fair: the same colour family, but not a straight swap. Flanker Light Blue is a little darker, warmer than Hellblau RLM 65.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 11). Flanker Light Blue is a little darker, warmer than Hellblau RLM 65.
The same difference applies the other way round: Hellblau RLM 65 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 Hellblau RLM 65 on the colour wheel See Flanker Light Blue on the colour wheel
All matches: Hellblau RLM 65 equivalents · Flanker Light Blue equivalents