W. E. Johns 
Kings of Space [EPUB ebook] 

When Group-Captain Timothy ‘Tiger’ Clinton and his son Rex take a holiday in Scotland, they expect to spend time in the great outdoors.Instead, lost in the fog while deer-stalking, they find themselves at the door of a mysterious, lonely castle, the home of a brilliant Professor. A brilliant Professor who has been building something incredible . . . a spaceship.Recruited to the Professor’s schemes, Tiger and Rex conquer the newest frontier — SPACE.These classic space stories by the legendary creator of Biggles are perfect for fans of pulp science fiction romps and classic Star Trek!