Interesting...I first happened across the Aviation in Ted Haigh's "Forgotten Cocktails", which points out that - although originally made with maraschino and violette - by the drink's heyday, it was only maraschino. And the Savoy Cocktail Book has no violette on its flight plan either.

And I've drunk all my violette...

So I'll continue mixing gin, lemon and maraschino and happily calling it an Aviation...but I'm curious about the purple.