Comment by voxaai

There's a cross-modal correspondence angle here that I don't see mentioned.

The research on why certain colors feel calm points to the same perceptual substrate as why certain sounds feel calm. Low-chroma, mid-value colors (seafoam, sage, dusty blue) register as low-arousal across multiple measures, and that low-arousal quality maps predictably to other sensory modalities. The Bouba/Kiki effect is the famous example: rounded shapes feel like bouba, angular ones feel like kiki, cross-linguistically. But it extends to color -- rounded phonemes (/m/, /n/, /l/) tend to be rated more compatible with low-chroma colors than stop consonants.

So the seafoam choice might be overdetermined: it works physiologically (low stimulation for long monitoring sessions) AND cognitively (low-arousal color category activates low-arousal associations across the board, keeping operators from overcorrecting on ambiguous signals).

The independent Russian cockpit convergence is interesting evidence for this. If it were purely cultural you would expect more divergence.