Looking through the overstock of my Grandfather’s bookstore, I have quite a number of Architectural Magazines, including many editions of “The American Architect,” “The Architectural Forum” (which actually covered Architecture, unlike today’s Architectural Forum, which almost no Architects read) and “The International Studio.” They cover the period from from the early teens to the late Thirties, but most fall between 1928 and 1934.
From the December 1930 edition of “The American Architect” there is an interesting article about Seadromes. Of course, no one today knows what a Seadrome is because they were never built, so this article is just about the only source I am aware of. There isn’t even an entry on Wikipedia. (Although there is a paragraph about them in the entry for Edward Robert Armstrong, the Engineer who had conceptualized and advocated the Seadrome concept.)
A Seadrome was to be a stopping point for transatlantic Airplanes, flying between Europe and North America. It was basically, an aircraft carrier on steroids, in that it had hotels & restaurants, as well as facilities to refuel and repair passenger airplanes. Of course, back then the largest passenger airplane held nine passengers, with a crew of three, so a passenger airplane wouldn’t really carry such a big load anyway. The intial plans called for the Seadrome to be 1,100 feet long, 340 feet wide at the middle, and 180 feet wide at the ends. The deck would be 70 feet above sea level. An interesting feature is that, as opposed to most designs for boats, which had solid hulls, the Seadrome hull was open between buoyancy chambers, allowing waves to pass through. “The resulting bending moments are thus reduced to a few percent of those incurred by a large steamer.” Of course, that sacrificed manoeuvrability, as the Seadromes were planned to be anchored semi-permanently at no fewer than 8 (!) locations along the route between Europe and North America:
I find it fascinating that such an elaborate and very expensive infrastructure was almost built (the contracts had already been let, according to the article, and 1/32″ scale model had been built and tested in Chesapeake Bay) when it was so foreseeable that it could so easily be made obsolete by long-range airplanes.
But the non-existence of Seadromes must have come as a surprise to some, because the article begins:
“The signing of Construction Contracts definitely assures the building of islands in Mid-Atlantic to service transatlantic seaplanes and to furnish hotel and restaurant facilities for their passengers.”
Was the development of airplanes of increased range so unforeseeable in December 1930?
I don’t think so. Perhaps these otherwise intelligent people were having their judgment clouded. My suspicion is that they were thinking in terms of analogies with automobile transportation, which had just come of age and had caused a very visible and expensive infrastructure of service stations, motels, restaurants, etc. to be built up to service that new mode of transportation. So those backing Seadromes just thought it was natural that a similar infrastructure would develop to serve long range aviation. Of course, they were overlooking the differences between long range aviation and long range automobiling.
They also failed to take notice of the fact that the development of the long range airplane hadn’t hit a plateau as the development of the automobile had. The automobiles, of 1930, though considerably less reliable, traveled about the same speed and had about the same range as my car does today in 2007. However, the Airplanes of today are almost six times as fast as those of 1930 were. (Cruising speed of the Ford Tri-Motor was a blistering 90 mph, although it could top out at 150 mph; a Boeing 767 flies at 540 mph) A Ford Tri-Motor held 8 passengers; the 767 holds 375.
So, for me the take-away is: to be very careful when using analogies in a predictive framework, and when doing so, be on the lookout for important inflection points, especially ones which might underlie critical assumptions of your framework.
What things do we think are about to happen, but those in future will look back and say “How could they have thought that would happen? In other words, What are the Seadromes of today?
Source: The American Architect, December 1930. “Transatlantic Flying a Commercial Reality through Man-made Islands” by J.T.W. Marshall, page 30-31 cont page 68.