My son Nick, who was screening a series of classic films for his friends, put on the 1981 Spielberg pulse-pounder, Raiders of the Lost Ark, which came out in the year he was born and therefore stood to him, in terms of the history of film and the decline of taste, as Casablanca does to me.
FOR MOST PEOPLE, THE MOVIE’S most memorable scene was the encounter between our bullwhip-wielding archaeologist hero and an Arab swordsman in a Cairo marketplace. After the would-be assassin puts on a menacing display of fancy samurai-style scimitar-waving, Indiana Jones, who has no time to waste, sets aside his usual sportsmanship and casually dispatches the black-clad virtuoso with a single revolver shot. Persons of unusually persistent memory may recall, however, that one of the film’s many other climaxes involved a fistfight between Jones and a gigantic shirtless Nazi – or Nazi employee, just following orders, since his party affiliation remained unspecified – underneath a big German aeroplane. That encounter ends when the certain victor in the unequal contest (that is, the giant) backs into a whirling propeller.
My son, showing that when it comes to a fondness for using big words – sesquipedalianism, I almost said – the fruit does not fall far from the tree, texted me: “Is the plane whose prop eviscerates a large bald man in raiders of the lost ark a real plane or is it a contrivance?”
No, I replied, the aeroplane was not real. But it was interesting nonetheless.
The plane was dreamed up by production designer Norman Reynolds. Designing a historically plausible and yet dramatic-looking Nazi aeroplane was not difficult, since the German aircraft industry was by far the most innovative of its time and came up with many stranger-than-fiction designs. It has been a fathomless mine of aeronautical nonce-formations, together with some remarkably prescient concepts.
‘The final concept of the plane featured in Raiders of the Lost Ark had four engines. By the time it hit the screen, it was down to just two’
The Reynolds aeroplane, a flying wing, seems to have been inspired by both an early Northrop prototype, the N-1M, and an abortive German project of a twin-engine fighter, tagged Li P.04- 106, conceived by the extremely smart and inventive Alexander Lippisch. The downward-turned wingtips of the Reynolds creation probably came from the original configuration of the Northrop aeroplane, the final version of which, with unbent wings and a brilliant yellow paint job, may today be found in the fabulous Udvar-Hazy annex of the National Air and Space Museum near Washington, D.C.. The strange dihedral joggle in the centresection, on the other hand, must have responded to some requirement that actors be able to jump onto, or from, the wing. Otherwise, it makes neither historical nor aerodynamic sense.
‘it looked more or less airworthy’
For the eponymous Ark of the Covenant, production designers had only to consult the Old Testament, which gives detailed instructions for its construction. I must have been getting popcorn when the reason for the Nazis’ interest in acquiring the Ark, or the Allies’ in retaining it, was explained. Generally speaking, the Germans displayed little interest in Hebrew memorabilia; nor did the Allies, until it was far too late, in rescuing European Jews. Screenwriters, however, are paid not to reproduce dismal reality, but to create alternative, and more interesting and uplifting, versions of it.
Apart from the strange centre-section and the structurally unlikely placement of the vertical fins atop the engine nacelles, the Reynolds design, or contrivance, looked more or less airworthy. Needless to say, it never flew, nor was it intended to. It suffered, instead, the unseemly fate of most large movie props. Exposed like Ozymandias to the elements on the abandoned Tunisian set, pillaged by souvenir-hunters, it was finally demolished, after ten years, by a bulldozer.
But that was not the end of its story.
About a decade after the release of the film, the German Aeroplane and its associated fistfight became part of a show called “The Indiana Jones Epic Stunt Spectacular” at the Disney World Resort in Florida. At this point the original prop already was, or was soon to become, dust in Tunisia, and at any rate it was probably too big to fit in the new show’s stage. A fresh, more conveniently proportioned German Aeroplane was required, and, incidentally, it needed to have tractor rather than pusher propellers and a much larger cabin, so that human actors could still climb into and out of the much smaller craft and could conduct their fight – which ended with the improbable disappearance of the large German in an antiseptic puff of red mist – in the space between the aeroplane and the audience.
A revised version was duly produced, with a bulging greenhouse cabin reminiscent of the famously asymmetrical Blohm & Voss BV 141, and with tractor nacelles elongated into booms supporting two vertical fins. The shape of the original wing, which with its sagging centresection, uplifted middle and downturned tips resembled an arthritic seagull, remained. Thanks to the general insensitivity of the non-specialist public to the appearance of technical things, many visitors to the Florida show probably left unaware that they had seen not the original, grand and now pulverized German Aeroplane, but a shrunken impostor – a nachgedunkelte Schrumpfgermane, as they used to call Josef Goebbels.
To the occasional bemused specialist, however, the natural question occurred: Could these confectionery German aeroplanes have flown, and if so, which would have been the better design?
The two wings were broadly similar. Cribbed from real flying-wing designs, they were tapered and swept, as is usually done in the absence of an empennage, to allow not only roll, but also pitch attitude to be controlled by what would be the ailerons of a conventional aeroplane.
The placement of the vertical fins atop the engine nacelles of the original version was structurally tricky, but not impossible. It was aerodynamically senseless, however, because, to the extent that the vertical surfaces were to have any stabilizing effect, they ought to have been as far aft as possible, and therefore to have been placed near the wingtips.
A more serious difficulty – and this is a challenge for any tailless design – was the position, rather far aft, of the engines themselves. Tailless aeroplanes have narrow CG ranges and require careful balance. Placing the engines too far from the centre of gravity makes balance impossible. The Northrop aeroplane solved the problem by burying its engines within the wings and driving the propellers through extension shafts.
The Mark II German Aeroplane, although differently arranged, was little better in this regard. Its engines were too far forward. The aft extensions of the nacelles put the vertical fins in a much more favourable location, but could not have been heavy enough to balance the engines unless some massive fixed equipment had been installed in them – perhaps two remotely-aimed gun turrets.
‘Tailless aeroplanes have narrow CG ranges’
By the same token that a wing-only aeroplane – in German, a nurflügel – has a narrow CG range, it has relatively weak longitudinal stability. Tractor propellers are destabilizing: When the nose comes up, tilting the propeller, the stream of air passing through the propeller is bent downward. The resulting equal and opposite reaction pulls the nose up farther. Tractor props are therefore not a good choice for a flying wing, especially one with powerful engines like the 1,200-hp Daimler-Benz V-12s that would have been the Luftwaffe’s likely choice, had this aeroplane really existed.
Apart from stability considerations related to this particular style of airframe, the tractor vs. pusher debate is of course an endless one. The tractor propeller operates in undisturbed air, but drives accelerated air back over the aeroplane, increasing its drag, and the fuselage or nacelle disturbs the path of the slipstream. The pusher propeller operates in disturbed air, but air that has slowed down with respect to the aeroplane; the slowing, in principle at least, improves the propeller’s efficiency. The distortion of the approaching flow field, however, impairs it. The choice is commonly dismissed as “a wash,” but the great majority of designers have preferred tractor installations, usually for secondary reasons like engine cooling, ground clearance, or the harsh noise that pusher propellers operating in an aeroplane’s wake inevitably produce.
Were these German Aeroplanes aeroplanes, or just contrivances? All things considered, it’s probably best that no one tried to take to the air in either of them. But, to be fair, they served their purpose, and, after all, it’s not so bad to be a mere contrivance. Aeroplanes are contrivances too.