@matigo There's no problem moving stuff in and out when you have an isolated facility with an airfield.
When he'd go out there in the 1960s and 1970s, it was always without notice, and they'd put him (and other personnel) on a standard-looking airliner at Burbank airport with the windows sealed shut. Then they'd fly in a random pattern for a few hours until they landed. The US government is (or used to be) very good at keeping things secret when it really wants to.
// @phoneboy @streakmachine