In Samurai Crafts I mentioned that Kuethe and Chow's book, Foundations of Aerodynamics, has a minor role in Helen DeWitt's novel, The Last Samurai. That was surprising to me because besides the rarity of the mathematics of aerodynamics being discussed, however briefly, in any literary novel, K&C's textbook was the one used in the introduction to aerodynamics course I took when I was an undergrad. The only difference being the edition mentioned in TLS was the 1986 one, and my class used the previous one from 1976. The first edition was published in 1950. The book was one of the best in the field, and maybe still is.
Ludo, the child prodigy and TLS's main character, receives a copy of an aerodynamics textbook from Sibylla, his mother, for his birthday; I think from the story's chronology it was his 7th, maybe 8th. I, on the other hand, didn't buy a copy of K&C until I was 20 or so. When I was 7 or 8 I couldn't spell aerodynamics let alone deal with its mathematics. At this point in the story the book's title isn't mentioned, and Sibylla buys it on the strength of the perceived humour in the passage about calculating the manoeuvrability of a grebe in water by approximating its body with an appropriately sized sphere, and on its use of classic 18th and 19th century math, which she thinks shouldn't be that difficult for her son to grasp.
It seems to me though that he does find it hard to grasp. There are several passages where Ludo picks up the text and tries to make headway, but soon puts it down in favour of some other book. It isn't until much later in the novel that Ludo confesses,
I put down Scientific American and picked up my book on aerodynamics. Sometimes I thought I understood it and sometimes it was hard to follow, and when it was hard to follow it wasn't easy to tell what would help; the thing that would really help would be to be able to ask someone who didn't sum up the mathematics required as 18th 19th century stuff. Any idiot can learn a language, all you have to do is keep going and sooner or later it all makes sense, but with mathematics you have to understand one thing to understand another, and you can't always tell what the first thing is that you have to understand. And even then either you see it or you don't. You can waste a lot of time trying to work out what you need to known and a lot more time just trying to see it.
When I read that a wave of deja vu and sympathy washed over me.
I'm an aerodynamicist by training, but I had a hard time with my first encounter with the subject. My introductory class seemed to me to approach the subject from a purely mathematical standpoint, and it wasn't clear why certain methods and assumptions were applied. The instruction had a strong air of 'that stuff should be quite self-evident' about it. I should note that the class wasn't taught to the K&C book; it turned out the book was only used as a reference. It took me a long time to dig into the experiments and observations of the early pioneers to finally appreciate why certain mathematical approaches were used. So, to be candid, it didn't help me that experts well versed in the mathematics of the subject were teaching it. What I needed was pre-mathematical insight into the physical nature of what was going on.
Back then I did a lot of reading into aerodynamics' early experimenters and writers. I eventually figured out that many of the fundamental physical insights and observations came from Fredrick W. Lanchester, and were discussed in his 1907 book Aerodynamics. I don't have a copy, but I borrowed it many times from the university library back in the day. The mathematical edifice Ludo encountered didn't exist when it was written, and it turns out it was the work that allowed practical mathematical approaches to be developed. I only mention this old thing because this pioneering work is a great combination of words and pictures, and that's what I think should be the first approach into the subject.
You don't need to seek out Lanchester's book as there are later ones that will give you a physical sense of the field and are light on the math, but don't talk down to you. I haven't practiced in the field for a very long time, so I'm not up-to-date on good recent books, but there are a couple of old ones that I like. One is The Science of Flight by O. G. Sutton. It was first published in 1949 and updated in 1955. It's a charming Pelican Book, and includes reprints of a number of the more crucial pages from Lanchester's book. Another choice is Aerodynamics: Selected Topics in the Light of Their Historical Development by Theodore Von Karman. It was first published in 1954, but Dover published the second 1957 version in 2004. A somewhat more modern choice is The Simple Science of Flight: From Insects to Jumbo Jets by Henk Tennekes. It was published by the MIT Press in 1997.
I guess from our vantage point 113 years after the publication of Lanchester's book, maybe aerodynamic flight does seem like a simple science, but I continue to think of it as The Beautiful Science. Flow visualization, along with physical observation, have been key to its development as has mathematical insight. I've found that triumvirate fascinating, and have often thought of aerodynamics as a form of sculpture, where what is being sculpted is the air around a moving body.
When I was Ludo's age there was a period when my father would sometimes take me to a local hill to fly a windup toy airplane. It was small and very forgiving in a crash, so it was easy to try and launch it over and over, making small adjustments, until we got a few nice flights. Even for an adult, if aerodynamics and flight is something you want to learn, that's where to start.
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