This problem is a lot harder than you think. æ sometimes becomes ae, sometimes becomes e, and sometimes becomes a. Which one is correct depends on the circumstances. For example, "encyclopædia" is normally written "encyclopaedia" in English and "encyclopedia" in American. And the name "Ælfred" is now normally written "Alfred".

You also forgot about œ, the crossed-out l thing that is used in Polish, the dotless i from Turkish, and no doubt others that I can't think of right now.