vimanas are aircrafts based on antigravity engine, which as i understood were comonly used in treta-yuga, lasting over 1million years before our kali-yuga began.
vimana is a sanskrit word, there is also Vailixi an atlantean more advanced aircraft. they even had cross-planetary mode, alowing to fly to other planets in other systems
i hope to encourage you to search and read about it.
like it could be the most epic book or a movie if it covered the whole Atlantean-Rama empire conflict and the way they disappeared.
this one illustrates how it could look in our age, particulary in russia))
painted with my friend AmiTara, who has a slightly different version on her page