And Buck Rogers comics from the 30's had tail-sitters before Heinlein. Some were rockets (tractor, from the nose) and some "ultronium" antigravity. http://nick

And Buck Rogers comics from the 30's had tail-sitters before Heinlein. Some were rockets (tractor, from the nose) and some "ultronium" antigravity. http://nick-stevens.com/wp-content/uploads/2016/12/buck-rogers-2.jpg http://nick-stevens.com/wp-content/uploads/2016/12/buck-roge...