Panel from Fantastic Four Annual #6 (November 1968), script by Stan Lee, pencils by Jack Kirby, inks by Joe Sinnott, letters by Sam Rosen
The Rail-Plane is powered by Annihilus's Cosmic Control Rod (available for 2.5 quatloos at every N.Z.T.A. (Negative Zone Transport Authority) station), so Reed Richards naturally takes the controls, even to my disappointment because we here at Comics Oughta Be Fun! all know that Ben Grimm can fly anything.
The Rail-Plane may well be inspired by an actual invention of Earth-1218 (that's our earth, for those of you without your Official Handbook of the Marvel Multiverse on hand) called the Bennie Railplane, which if I hadn't seen a photo of I would have sworn that artwork just below was a fictional creation of Bruce McCall:
While the Negative Zone Rail-Plane rides on fins that fit into a slot, making it the original slot-car racer, the Bennie Railplane is pulled by propeller along an overhead wire. You can see it in action in this amazing period clip that the National Library of Scotland won't allow us to embed, thus re-inforcing that very unfortunate ethnic stereotype of the Scottish...as a people who won't let us embed their videos. Why, what did you think I was going to say? BULLY DON'T DO THAT.
George Bennie's railplane was demolished for scrap in the 1950s. Annihilus's was demolished for food by the Borers:
Since I'm not likely to have a feature any time soon that covers 365 Days of Jack Kirby Monsters, here are the Borers.
They're the Borers! Keep them away from your exciting parties!