Another comment mentioned green vs white. Even though it's practically impossible to get an aviation license with deuteranopia that just seems like it's asking

Another comment mentioned green vs white. Even though it's practically impossible to get an aviation license with deuteranopia that just seems like it's asking for trouble. White light is rarely pure white and depending on the weather conditions I have a hard time believing the contrast is unambiguous. Heck, maybe aviation should take a page from basic accessibility and figure out that information should be conveyed more than one way. Don't rely on color alone (and no, spacing of the rows of lights isn't unambiguous either, especially when looking at varying distances and angles).