JF Ptak Science Books

"Small Target Bombing Probabilities"--Bombing Calculator, 1944

JF Ptak Science Books  Expansion of an earlier post from  2011 

I found this object in my paper-calculators box (moveable disk calculators made of paper, two going back to  Fr. A. Kircher in the 1680’s)—I’m not sure why it was there as it is not paper, though it is an interesting calculator.

[Images are greatly expanded in click mode.]

You can learn or re-learn an interesting lesson from it on bombing accuracy.

The “Small Target Bombing Probabilities” calculator was issued by the little-known (in the popular sense) Applied Mathematics Panel of the National Defense Research Council (NDRC)¹ in the early 1940’s during WWII. 
Marked “Restricted”, it calculated the number of bombs that would successfully be delivered given (1) the number of bombs, (2) the “aiming error”, and (3) target size. It would then generate results for “(a) the expected number of hits for the indicated number of bombs”, (b-e) the probability of at least one hit to four hits.

What is a little surprising to me was the number of bombs that didn’t find their target. For example, a 65,000 square foot target bombed with 1000 bombs and an aiming error factor of 2000 feet could expect to land 3-4 bombs on the target, with an 88% chance of landing at least two hits, 75% chance of landing three hits, and about 50% of landing at least four hits.  And so the necessity of large numbers of planes dropping a large number of bombs.  

Notes

1. The establishment of the NDRC was announced so: “It is announced by Science Service that the following committee has been appointed in the United States to correlate "scientific research on the mechanisms and devices of warfare": -- Nature 146, 191-191 (10 August 1940).

“Members included: Dr. Vannevar Bush (chairman), president of the Carnegie Institution of Washington, formerly dean of the faculty of engineering at the Massachusetts Institute of Technology; Prof. Richard C. Tolman (vice-chairman), dean of the graduate school and professor of physical chemistry and mathematical physics at the California Institute of Technology; . Dr. Irvin Stewart (secretary), formerly Federal Commissioner for Communications and chairman of the Committee on Scientific Aids to Learning; Rear Admiral Harold G. Bowen, director of the Naval Research Laboratory, Anacostia, D.C.; Conwiy P. Coe, U.S. Commissioner of Patents; Dr. Karl T. Compton, president of the Massachusetts Institute of Technology, formerly professor of physics at Princeton University; Dr. James B. Conant, president, formerly professor of organic chemistry, Harvard University; Dr. Frank B. Jewett, president of the Bell Telephone Laboratories; Brigadier General G. V. Strong, assistant chief of staff, U.S.”

Your Daily Dirigible (1913)

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Well, no, this is not really a "daily" dose of dirigibles, though it is a nice display of the airships. This double-page display is found in the Illustrated London News  from 22 February 1913, illustrating a short article addressing the need for legal reform in the flight of dirigibles, particularly in regards to the airships being used in possible combat.  WWI wasn't far off at this point, and the ILN takes its readers on a quick tour of who-had-what in regards to the airships, depicting German and French airships and aerodromes. If you click on the images and then click again you'll see that there is info on individual airships as well.  

Click to Expand

Details follow:

Gliding Flight and The Seventh Seal (1897)

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Science heavyweight and Nature editor and founder J. Norman Lockyer wrote in 1897¹ a three-page summary of the recent experimental work of aviation pioneer Percy Pilcher. Mr. Pilcher (1866-1899) was rather more than a "pioneer"--he was an inventor and perhaps Great Britain's premier experimentalist and visionary in flight at the end of the century—and made significant contributions towards understanding flight dynamics, though he would not live out the century, fatally crashing in a glider flight that was leading towards the launching of a powered glider of his own design.

The article was accompanied by a seven-part rapid-photo series of Pilcher in flight, and what caught my eye in this series were the small figures on the rolling hill under the glider. Enlarging the image quite a bit (the originals in Nature shows figures only 3mm tall) brings proto-post-Swedish-noir to mind, especially the very animated figure on the right and  particularly for a famous scene from Bergman's Seventh Seal (1957):

 

 

 

 

 

 

 

Notes:

Sir J. Norman Lockyer (1836-1920), long-time experimentalist/instrumentalist/theoretician who worked in astronomy and spectroscopy and was co-discoverer of helium (found in the atmosphere of the Sun).

1. (PILCHER, Percy.) Lockyer, William J. "Soaring Flight", in Nature, a Weekly Illustrated Journal of Science, 12 August 1897, vol 56 no. 1450, pp 344-346 in the issue of pp 337-360.

And the full series of photos:

On Flying Machines--Scientific American, 1848

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I found a short article on human flight ("Flying Machines") in the fourth volume of Scientific American (1848).  It is an interesting and occasionally predictive piece that saw a bit into the future, well past the contemporaneous failures and iron-punk possibilities of sky machines, into a place of "mathematical certainty.  The writer saw the possibility of heavier-than-air flight, only just not in 1848 (or any time soon). "The air furnishes a vast fund of power for the use of mankind, although as yet they have only used it to propel ships and wind-mills. We live in an age of great discoveries and improvements, and among these will certainly be ranked the navigation of the air." 

And so some snippets from the article: 

"Flying Machines and Perpetual Motions are very old and unfortunate acquaintances. No people have invented so many as the Germans, and many a poor fellow has lost his life by his fool hardy confidence in some machines he had invented to ride upon the winds, yet for all the accidents that have taken place to high flyers, from the Dutch Doctor at Ratisbone in 1692 to the unfortunate Englishman who perished a few years ago in London when descending by a parachute, there are still to be found new flying machines coming out every few months. An Austrian made quite a fine display in Cremone Gardens, London last winter, by taking several long jumps with a steam flyer. Since that we have heard no more about it, and presume it has met the fate of its illustrious predecessors...

"But the end of flying machines is not yet, and here we insert the description of a new and an original one certainly, taken from the Jacksonian published at Pontiac, Michigan... After describing how wings had been tried to beat the lark and eagle, he says:—“As wings then, have failed, and balloons been attended with no better success, men have begun to think that the end is unattainable, and that flying is a victory which man can never achieve."

"The Fine Sport" of Flying, 1893.

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I found an interesting article in Nature¹ just now,  a piece by Carl Runge on 19th century heavier-than-air human flight by the remarkable Otto Lilienthal. 

Lilienthal was an international authority on human flight, and was known to many as The Flying Man, and The Father of Flight, because, well, he flew. And he flew more often and with more recorded/documented successes in his non-powered flying machines than any other aviation pioneer of the time. In fact, he had a major influence on the Wright brothers (though not necessarily for his experimental data, which they abandoned after a while to create their own in their wind tunnel), with Wilbur Wright saying: "Of all the men who attacked the flying problem in the 19th century, Otto Lilienthal was easily the most important. ... It is true that attempts at gliding had been made hundreds of years before him, and that in the nineteenth century, Cayley, Spencer, Wenham, Mouillard, and many others were reported to have made feeble attempts to glide, but their failures were so complete that nothing of value resulted." (From the Wikipedia article on Lilienthal.)

Lilienthal was well into making  successful jumps/flights by this time, but would suffer his fatal fall in about two more years, dying August 10, 1896, after a series of 850' flights. (I'm offering a later paper on Lilienthal, also available on ABE, from Nature for 12 December 1894.)

The last three sentences by Runge are remarkable:

"If it [flying or attempting to do so]  is taken up by a great many people, improvements of the apparatus are sure to follow, and the art of keeping one's balance in the air will be developed. Perhaps this is the road to flying. At any rate it must be fine sport."

Notes:

1. (LILIENTHAL, Otto). Runge, C. "Experiments on Flying", in Nature, a Weekly Illustrated Journal of Science, 14 December 1893, volume 49 no. 1259, pp 145-168, with the Runge article on pp 157-8, with three photo illustrations of Lilienthal in flight.

Cutaway View of the Cockpits of the Hawker Hurricaine and Messerschmidt (1942)

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I think that there are several dozen aircraft cutaway and cross section aviation schematics on this website, and tonight's main entry is for the British (Hawker) Hurricane (predominantly by Hawker Aircraft Ltd.) followed by a small inset of an (unnamed though I'd guess the 109) Messerschmidt of the Luftwaffe. The image is found in the August 1942 issue of Popular Mechanics, which has hosted a number of these sorts of displays of information.  

 

Lunar Space Suits, 1950

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This is just a very quick post based on a book that I'm trying to sell over on the bookstore end of this blog--the images are arresting and interesting, and I at least wanted to share them here.  These two illustrations are the first serious scientific study of what sort of suit would be needed to survive on the surface of the Moon (according to the Space Centre UK website) and appear in  H.E. (Harry) Ross' article “Lunar Space Suit” as it appeared in the  Journal of the British Interplanetary Society, (vol 9/1, January 1950) . Enjoy. 

“In a November 1949 symposium, Harry Ross presented a paper on the “Lunar Space-Suit”. Ross had examined the problem of a 68 kg lunar space suit (equivalent to 11 kg on the Moon) which could be worn for up to 12 hours, within the temperature range of 120 degrees to minus 150 degrees Celsius, representing night and day. The suit design was a 4-ply, made up of a thin exterior skin of closely woven cloth. It had a 1 cm layer of cellular heat-resisting material (Kapok, wool, felt et cetera) and a 1-2 mm main airtight sheath of fabric-backed natural or synthetic rubber. It also had an interior lining of non-hygroscopic material, mainly for comfort and to manage contact between the rubber and skin and absorption of the water-vapour. The exterior of the lunar space suit was to be a highly burnished metallic film, designed to reflect as much heat as possible.”

“The helmet was to be a light, rigid double-shell structure, with the inner a bright alloy metal and the outer a plastic with burnished metal coating. Lateral vision of 180 degrees was proposed with a minimal vertical extension in order to minimise heat gain or loss. A special glass to prevent heat and actinic Ultra-Violet rays would be employed...”

“The space suits that were eventually worn by the Project Apollo astronauts are a far cry from this original 1940s design. But the work started out by Harry Ross, led to credible thinking on how humans could survive in a self-contained, mobile habitat. The original paper by Harry Ross is [this paper].” --British Interplanetary Society website

Zed + Zero Zeppelins = No Zeppelins at All (1913).

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I knew I needed to do something with this tremendous image (found as you can see in Scientific American for 16 August 1913) and thought it might be nice to make something of it rhyming "zeppelin" all the way through...but there aren't very many single words that do that, though if you cheat a little you can have a lot of two-word constructions with the second word being "in" that would close the gap. Anyway, that's not all that fruitful or interesting, so I'm just going to note that this composite image depicts Zepps on their way to be zero and zed following their zigs and zags through the sky. It is an attempt--I think--to show that in spite of their tremendous size and threatening nature, the Zeppelins could break just like everything else.  

Defining What "Flying" Is, or Was (1894)

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What does “flight” mean, anyway? How much do you have to be off the ground for something to be “flying”? If the answer is “two feet off the ground for 500 feet”, then Hiram Maxim did indeed succeed in being the first to construct a heavier-than-air aircraft that “flew”. Perhaps this definition might be a little broad, or narrow, though it does make falling sound like flying, too.

In any event, that is what Mr. Maxim (1840-1916) did on 31 July 1894 with his enormous aeroplane as reported in the Scientific American of 15 September 1894 ("Maxim's Flying Machine").  He invested a good amount of money in the project funded by his tremendously successful “Hiram gun”, creating a number of aircraft before settling in on a great beast of a flying machine in 1894.

The image of the aircraft is a perspective looking up at it, as though it were in flight. It wasn't, though it was a semi-romantical thought and presentation. It had big numbers: 7000 pounds, 17.5' diameter propellers, 2 steam-powered 180hp engines, 120' long and 105' wide, and 8” cylinders with a 5” stroke. Big numbers.

One of the images that really struck me though was the steam chamber, which looks absolutely huge (though I can't find dimensions for it), but you can make it out on the aircraft's bow. For test runs 600 pounds of water were needed—2500 pound were needed to generate lift.

So back to the “flight” issue; Mr. Maxim was on board the 3-person-crew aircraft on the day of the test. The aircraft was tethered to an 1800' wooden rail to prevent it from actually taking off if it could...I think mainly because they were really just testing lift, as controlled flight was still yet another enormous issue. The aircraft did manage to achieve lift two feet above the rail, but the force was so great it ripped up the rail and crashed. (Mr. maxim found himself in a somewhat similar position to that of Frankenstein when overpowered by the monster which he himself had fabricated and endowed with life.") No one was hurt, though the aircraft was decimated. As the writer in the Sci Am stated, "the ride in this way was brought to a sudden stop, and it will be several months before it can be renewed". It isn't anything like the Wright's flight nine years later, though some do consider this Maxim experiment to constitute a “first flight”.

One thing is certain: it was a lovely and impressive thing that Maxim built--it wasn't elegant by any means, though it had a certain crushing charm to it.  

Here's a photo of the aircraft (with a person standing right there in front of it, for scale):

(Image source: ctie.monesh.edu.au/hargrave/maxim.html)

Light Bombs, 1913

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In the earliest periods of the history of bombing it seems as though the among the first generations of "bombs" dropped from flying machines were "light" or light sources, as we can see in this pair of illustrations from the Illustrated London News for 30 August 1913. These weapons appeared almost two years after Lt. Giulio Gavotti dropped an actual explosive from his plane on 1 November 1911 in a battle of the Italo-Turkish War¹. Not that the exploding bombs weren't  heavy (they weren't) but that the feature of the weapon dropped in the 1913 case was capable of generating a penetrating or at least illuminating light.  We are told in the legend of the print that the light-bomb dropped from the dirigible was attached to a parachute which opened immediately, and from the height of 1500 ' at release the writer states that it would take the weapon three minutes to descend to the ground. (Of course the illuminated area would get together an tighter in descent, though it seems like there would be a good minute of so where there was some intelligence gathering possibilities.)

Even though this package wasn't exploding, it did provide the observers from above time to gather information on the position of the enemy and relay that data so it could be employed in tactical or strategic manners.  

Notes:

1. Lt. Gavotti (1882-1939) actually dropped four four-pound grenades from a height of 600' from his Etrich Taube monoplane in action against the Ottoman Turks in Libya. This was the first instance of bombing from a heavier-than-air aircraft, bombs being dropped from balloons for several decades already by the turn of the century. Dropping bombs from balloons was deemed an illegal act of war and outlawed in the Hague Convention of 1899--but as the Wright flight was still a few years away at that point there was no provision established for bombing from aircraft that didn't yet exist.  There were other instances of bombing from aircraft before the start of WWI, with the first instance during the Great War occurring when German Zeppelins bombed the city center of Antwerp a few weeks after the war began on 24 August 1914. The Brits launched an aeroplane attack  against two Zep bases in Cologne and Dusseldorf in response, and, well, and so on, raids and bombs becoming more sophisticated, cities becoming targets, and the race to destruction became developed. 

Images are expandable.

 

Floating Mines of the Air (1939)

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 This thrilling nail-biter from the near future appeared in Popular Mechanics for December 1939.  What we are seeing floated here (sorry/terrible) was a system of relatively primitive helium-filled air mines to guard against enemy attack from the air.  There was no doubt the (fighting) end of the European and British part of WWII there would be a very major role played by aircraft. Bombing had already been introduced on a larger scale with German practice and assistance to Franco in Spain, and of course there was plenty of evidence for air power in the crushing of Poland just a few months earlier beginning 1 September and ending 26 days later--a victory and a defeat that shocked the military world. So much of the world had entered into war in the first two weeks of September 1939, and of course the U.S.  reacted with predictable strong sentiments for isolationism.

I remember a headline--can't place where--reading it, years ago, announcing that the Olympic Games for 1940--that were to be held in Soviet-attacked Finland--were cancelled.

There was a simple idea behind the aerial minefield--take 5' diameter balloons, fill them with helium, attach a 40' line to it on one end with a bomb with 4 lbs of high explosive on the other; send them aloft, and then wait for a plane to hook one of the lines with a wing or tail or something. These were to be sent aloft by the hundreds if not thousands. Maybe this could work, I dunno--but what comes to mind is what happens with the hundreds of balloons that didn't have something run into it?  They bomb would explode on contact, so at some point, they're all going to come down... There'd that, plus what if fighter planes came in before the bombers (once the Germans were close enough that is) and simply shot down the balloons? I imagine that they'd be used over rural areas where there could be some absorption of hundreds of falling failing bombs. Anyway, this idea seems a little problematic.    

The USAF "Flying Saucer" Prototype (1954)

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Appearing as a splashy double-page spread in LIFE magazine for May 31, 1954 is the great “Project Y” USAF flying saucer. It was the continuation of the work carried out by John C.M. Frost (1915-1979) who was a superior engineer who worked for de Haviland and Avro Canada, and who continued his VTOL work with the Air Force under the “Project Y”. This aircraft was to fly 1500-2000 mph and have a 1500 mile range. Of course, this particular aircraft didn't get very far for Frost, a person with numerous successes, but it did experience some fair amount of attention.

A Double Dose of Dirigibles

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There's nothing quite so satisfying as seeing a representation of quantitative data where the graphical displays are flying.  "One Dreadnought Buys 52 Dirigibles and 235 Aeroplanes" is a full-page diagram appearing in the 3 June 1911 issue of the Illustrated London News , making a very strong point that in the new age of aviation the 2 million pounds it would cost to produce one battleship could also (or rather) buy a lot of aircraft. 

You may notice that the ship is flying a U.S. flag--this is because the graphic appear a month or so earlier in the U. S. publication Scientific American, and the ILN is simply reprinting the info  In any event the image enumerates U.S. and international aircraft, making for a lovely representation of a broad range of airplanes filling up the same sky. 

A World of Untranslatable Colors and no Color Vocabulary (1638)

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There was something that caught my eye as I paged through an online copy of Francis Godwin's The Man in the Moone or A Discourse of a Voyage Thither by Domingo Gonsales (1638), something beside this work being about the first English language trip to the Moon. There were other earlier trips made to our friendly neighbor before Godwin (whose work was published posthumously) like the late Greek Lucian first century ACE).  And there were contemporaries who wrote in other languages, like Cyrano and Kepler (Somnium, 1638); Aphra Behn’s farce (The Emperor of the Moon 1687) and Margaret Cavendish  (The Blazing World 1688); and John Wilkins (The Diversity of a World in the Moon, (1638) to name a few...and then there's the wide world of the plurality of worlds, like the wonderful Fontenelle...and of course later there were trips to the Moon made by Verne and Wells, and so on.

Godwin's book is short and quick, deceptively simple but not so—there's a bit of introduction where we are shown a little bit of the influence of Galileo's Sidereus (1610), and the frontis depicts the flying machine by which the intrepid traveler, Senior Gonsales flies off to the Moon. This is a craft powered by a sort of wild swan, which struggles mightily to free itself of the Gilbertian great magnet, but once free of that, the “flight” took twelve days. Our traveler may also be the first one to get to the Moon by accident: he flees a fiasco in which he kills someone in a duel winds up in St. Helena, and then has a problem with the British fleet off Tenerife, from which he flies off again with his bird machine...he hadn't intended to go to the Moon, but that is what happened.  

Here's what I found so interesting: once he gets there, Gonsales tries to describe clothing and—even more fascinating—he tries to find words for colors that he has never seen before. Marvelous.

“[T]heir colour and countenance [was] most pleasing, and their habit such, as I know not how to expresse. For neither did I see any kind of Cloth, Silke, or other stuffe to resemble the matter of that whereof their clothes were made; neither … can I devise how to describe the colour of them ….

It was neither blacke, nor white, yellow, nor redde, greene nor blew, nor any colour composed of these.

But if you ask me what it was then; I must tell you, it was a colour never seen in our earthly world, and therefore neither to be described unto us by any, nor to be conceived…. Only this I can say of it, that it was the most glorious and delightfull, that can possibly be…."

And that, I'm afraid, is where I left off. As I've said elsewhere on this blog I only give each one of these post an hour's time maximum, and after my fumbling around in the Godwin, I'm about at my limit. This much-studied book deserves a lot more than what I can give it here in 700 words, but this will have to do for now, for me. The bottom line here is that I don't think that I've ever read anything by anyone before, say, 1920 and the real birth of the sci fi genre (with which I'm am not very familiar) that tries to describe a color that was without description. 

[Image source: Wikipedia Commons.]

Oh, before I go, Godwin also introduces us to the imaginary language of the Lunarians, which he describes as being beautiful, and very expansive, as the vocabulary can change given its tone. (He also notes that only one language is spoken on the Moon, which he credits as an advantage over the terrestrial polyglot.) This is also part of a long history of imaginary languages in early literature (for example, More's Utopia and Rabelais' Gargantua...)  The Lunar world is a Utopia, and evidently part of that blissful state is maintained by trading out ill-behaved Lunarian children with well-behaved children of Earth. 

Non-Silhouette Silhouettes and Dirigible Mooring Masts (1930)

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Just a very quick entry here on some interesting and arresting images relating to flight, all from the July-December 1930 volume of Popular Mechanics. The first is a full-page illustration for October (1930) showing an improved method for anchoring dirigibles--in this case, for demonstration purposes, it is His Majesty's Airship airship R-100, which was over 700' long and moved along at about 80 mph, and was less than a year old. Unfortunately, this protocol for moving though the air was nearly exhausted--it was fateful for this note on the mooring masts appeared in October as this was the month of the R-101 disaster, which effectively brought the end of the R-100, which was scrapped soon afterwards.  

• "Sketch of Latest Type pf Mooring Mast for Dirigibles, Showing the Lights, Tackle and Winches Used in Bringing a Big Airship to Anchor: Note the Ground lights That Indicate the Direction of Wind ..." 

The other image of aviation interest is a chart of airplane types and how to identify them in silhouette--except that they are not in silhouette. Still it is a handy chat, and I reproduce it here: