Today I recieved a couple fligth manuals from someone my mom knows and they were US Navy flight manuals for the P2Vf,DC-9,and C-54(Note this doesn't include all the manuals just sections) They are dated the earliest 1959 and the latest is 1969 is it legal to own these? It says Confidential on some of them and it says

"Notice-This documant contains information affecting the national defense of the US within the meaning of the Espionage Laws,Title 18,U.S.C.,Sections 793 and 794. The Transmission or the revelation of its contents in any manner to an unauthorised person is prohibited by law."

I'm soooooo worried that I could get in trouble for owning these things. 

I'm sure they're more interested in not losing the secrets inside their drones rather than aircraft manuals from by-gone eras. 

Wikipedia says that documents in the USA become declassified after 25 years, although agencies who have a relevant interest in those documents remaining classified can keep them as such. I can't speak for the legality, but I really don't think they'd be all too concerned.