This originally came to my attention via Jess Nevins, who goes on to explain where this came from:
The poster to the tragically-unmade Hammer film Zeppelin v Pterodactyls.
(Ganked from Airminded, which will be of minority interest to most of you, but of great interest to a few).
Airminded provides a link to this plot summary:
"The story was along the lines of THE LAND THAT TIME FORGOT, with a German Zeppelin being blown off-course during a bombing raid on London and winding up at a “lost continent”-type place."
Zeppelin v Pterodactyls would have been the Hammer version of David Allen's Raiders of the Stone Rings, later called The Primevals.
Ah, what might have been.
Of course, what we need now is the sfx team behind Sky Captain and the World of Tomorrow to hire a good team of writers and make Zeppelin v Pterodactyls.
I’d certainly be up for a story that used something like this as a springboard (so not just a “look it has Zeppelins and pterodactyls in it, type of affair you might get from the Syfy Channel”) - a Steampunk Valley of the Dinosaurs or some kind of period Hollow Earth tale and now I type that I realise I might have something in the pipeline that could set up something like this, just without the biplanes. Another one to ponder.