This is pretty much a duplicate of
Closing as "belongs on another StackExchange site" and Migration to Travel.SE although both the answers to those questions seem to cite that because Aviation.SE is in Beta, it will have to wait.
Well we did it, we graduated and now we can play with the big boys. Can we revisit this topic?
As of right now it seems that the only site we can suggest it be transferred to is Aviation Meta, which is far less common of a migration path than Travel.SE or Physics it would seem.
The second question has an answer that suggests that "it happens infrequently", but I think it happens frequently enough, plus I'm not sure what the harm is in adding it there as a suggestion, it should be much better needing 5 votes to migrate than everybody raising a moderator flag.
So the question is: Can we add Travel.SE and Physics.SE to the "belongs on another StackExchange site" close vote?