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Wednesday, June 28, 2023

Thoroughbred

Thoroughbred (pronounced thur-oh-bred, thur-uh-bred, thuhr-uh-bred)

(1) Of pure or unmixed breed, stock, or lineage, as a horse or other animal; bred from the purest and best blood; a pedigree animal; purebred.

(2) By analogy, a person having good breeding or education.

One of a breed of horses, to which all racehorses belong, originally developed in England by crossing three Arabian stallions with European mares (always initial upper case)

(3) By analogy, a machine built to exacting standards with mostly bespoke parts rather than something assembled from parts or components from other manufacturers.

1701: The construct wass thorough + bred.  Through is traced to circa 1300, from Middle English thoruȝ & þoruȝ, an adjectival use of the Old English þuruh (from end to end, from side to side, a stressed variant of the adverb þurh), a byform of Old English þurh, from which English gained through.  The word developed a syllabic form in cases where the word was fully stressed: when it was used as an adverb, adjective, or noun, and less commonly when used as a preposition.  Bred is the past tense of breed.  Breed is from the Middle English breden, from the Old English brēdan (bring (young) to birth, procreate (also "cherish, keep warm), from the West Germanic brodjan (source also of the Old High German bruoten, & German brüten (to brood, hatch)) & the Proto-Germanic brōdijaną (to brood), from brod- (fetus, hatchling), from the primitive Indo-European bhreu (warm; to boil, bubble, effervesce, burn).  It was cognate with the Scots brede & breid, the Saterland Frisian briede, the West Frisian briede, the Dutch broeden, the German Low German bröden & the German brüten.  The etymological notion is incubation, warming to hatch.  The intransitive sense "come into being" is from circa 1200; that of "beget or bear offspring" from the mid-thirteenth century.  As applied to livestock, the meaning "procure by the mating of parents and rear for use" was standardised by the mid-fourteenth century.  The sense of "grow up, be reared" (in a family; clan etc.) is from the late 1300s, extended to mean "form by education" a few decades later.  Thoroughbreed (also as thorough-breed) is a now rarely used alternative form.  Thoroughbred & thoroughbredness are nouns; the noun plural is thoroughbreds.

Among the thoroughbreds:  Lindsay Lohan visiting Flemington Racecourse for the Spring Carnival, Melbourne, Australia, November 2019.  Melbourne Cup Day (left) and Derby Day (right).

The noun breed "race, lineage, stock from the same parentage" (originally of animals) dates from the 1550s, derived from the verb but wasn’t applied to people until the 1590s; the scientific use to define a “"kind or species" began to be used in the 1580s.  The noun half-breed (person of mixed race) is attested from 1760 and was used first as an adjective in 1762; now though offensive it appears to have been replaced by “mixed-race”  but even this is not recommend for use unless being applied self-referentially.  The verb cross-breed appeared in 1670, used in relation to dogs, livestock and plants and, surprisingly, appears not to have been a noun until 1774.  Underbred (of inferior breeding, vulgar) from the 1640s was an adjective which didn’t survive; it was applied to animals "not pure bred" after 1890.

Thoroughbred the adjective dates from 1701 in the sense of persons "thoroughly accomplished" and wasn’t used for horses until the concept was created in 1796; the noun is first recorded 1842 but it’s hard to believe if wasn’t earlier in use in the horse-racing business; the noun is first recorded in 1842.  Use to refer to racehorses soon became definitive and all other applications are now analogous.








Needs a trained eye.  Thoroughbred (Indy King by Mr Prospector out of Queena) on the left, Standardbred to the right.

Sometimes casually used to refer to any purebred horse, it’s correct to use the word only with the Thoroughbred breed.  If used with a lower-case "t", it technically may be applied to just about any object when appropriate but never with other horse breeds.  It can cause confusion or worse. 

The Thoroughbred was bred in seventeenth and eighteenth-century England when several dozen native mares were crossbred with three imported Oriental stallions, Byerley Turk, Darley Arabian and Godolphin Arabian; all Thoroughbreds can trace their pedigrees to these three.  Between the 1730s and the late nineteenth-century, the breed spread throughout the world, first arriving in Australia in 1802.  Bred mainly for (gallop but not trotting or pacing) racing, they are also used for show jumping, combined training, dressage, polo, and fox hunting.  Thoroughbreds born in the Northern Hemisphere are officially considered a year older on the 1 January each year; those from the Southern Hemisphere having their birthday on 1 August.  These artificial dates enable the synchronization of northern and southern competitions for horses within their age groups.  Thoroughbreds are bred for speed, and depending on their intended career, for endurance over distances less than a mile (1600m) or as long as four (6400m).  They have a reputation for being highly-strung, sometimes deserved, sometimes not.

A horse cannot be registered as a Thoroughbred unless conceived by natural means; any form of artificial insemination is banned.  The industry maintains there are all sorts of reasons for this but it’s really a restraint of trade designed to limit supply and maintain high prices.  One charming second career for a Thoroughbred stallion which has proven too slow to race is that of a teaser.  A teaser’s job is to be placed close to a mare, usually behind a fence, to see if she’s in the mood to mate.  If she proves receptive, the teaser is led (unwillingly one supposes) away and replaced with a fast stallion.  Nature is then allowed to take its course.

The Maserati 5000 GT (Typo 103, 1959-1966)

1957 Maserati 450S.

It’s never taken much to induce advertising agencies to describe a car as a “thoroughbred”.  Some have been more convincing than others but few have been as deserving of the appellation as the Maserati 5000 GT (Typo 103).  With coachwork fabricated by eight different Italian coach-building houses, all of the thirty-four built used a slightly tamed 4.9 litre (300 cubic inch) variant of the 4.5 litre (273 cubic inch) V8 last seen in the Maserati 450S with which the factory’s racing team contested the World Sports Car Championship.  It really was end of the era stuff, a shift to unitary construction soon dooming most of the specialist coachbuilders while increasingly interventionist governments were in the throes of passing a myriad of laws which would outlaw barely disguised racing cars being used on the road.

1959 Maserati 5000 GT (Shah of Iran) by Touring.

In keeping with the pedigree of its illustrious engine, the 5000 GT enjoyed a blueblood connection in its very origin.  Before the Ayatollahs ran Iran, it was ruled by the Shah (king) and he got a lot more fun out of life than his clerical successors, noted especially as a connoisseur and of fast, exotic and expensive cars, his collection including multiple models from Lamborghini, Mercedes-Benz, Rolls-Royce, Ferrari and Maserati among others.  In 1958 he’d driven Maserati’s then popular 3500 GT but thought it lacking in power and, because hundreds a year were sold to the (rich) public, a bit common.  Accordingly, after receiving material advertising both the 3500 GT and the remaining 450S race cars the factory wished to dispose of after withdrawing from racing, the shah decided he wanted a combination of the two, the race engine in the road car.  To have it created, essentially he sent Maserati a blank cheque and asked them to call when it was ready.

1962 Maserati 5000 GT by Allemano.

It wasn’t as simple as it sounded for the 450S V8 was not some adaption from a production car but a genuine racing engine designed for use nowhere but the circuits and only in the hands of skilled racing drivers. Robust and powerful it certainly was but it was also raucous, inclined to roughness at low speeds and not all that well behaved except when at racing speed when it was more raucous still, if a little smoother.  Taming such a beast for the road was a challenge but, with the shah’s buckets of money and some Italian ingenuity, remarkably, a relatively quiet and tractable engine (compared with that of a race car) was concocted.  The bore-stroke relationship was changed, the camshaft profiles softened and the porting was altered, which, combined with a lower compression ratio, improved torque and delivered the still ferocious power over a more usable range.

1959 Maserati 5000 GT by Allemano.

Italian house Carrozzeria Touring designed one of their signature superleggera (their clever technique of lightweight construction) frames, onto which they attached a hand-made skin of aluminum to create a strikingly modernist two-seater coupé, its lines and interior appointments influenced by Persian Baroque architecture.  Delivered to the shah (Mohammad Reza Pahlavi, 1919-1980) in 1959, it was almost a secret but when a second, commissioned by a South African customer,  was displayed at the 1959 Turin Motor show, it generated such interest that Maserati were soon fielding enquiries from rich commoners wanting what royalty had.  Priced stratospherically however, there weren’t enough rich folk on the planet to make it a viable option for their production lines so it entered the catalogue as a bespoke item, Maserati modifying the 3500 chassis which, frankly had been a bit over-taxed by the big V8 and tweaking the engine still further, slightly increasing the capacity but in a way that rendered it more docile, yet still a howler when stirred.  The chassis appeared in the list and buyers could choose their own coachbuilder and eventually eight produced their own interpretations, the most numerous being by Carrozzeria Allemano which, over the years, finished twenty-two, the Allemano cars thought also the most alluring.

1963 Maserati 5000 GT by Fura.

It was capable in some of the configurations in which it was supplied of 170mph (275 km/h), the fastest road car of its day, almost matching the 183 mph (295 km/h) achieved years earlier by the Mercedes-Benz 300 SLR “Uhlenhaut” coupé, which was little more than a Formula One car with a bigger engine and number plates.  The 5000 GT was quite something and even if the early versions weren't exactly suited to urban use, they were never anything less than exciting.  All the 34 built still exist, most percolating between private collections, high-end auction houses and the odd appearance at an appropriately exclusive Concours d'Elegance.

The Gordon-Keeble GK-1 (1964-1967)

1965 Gordon-Keeble GK-1.

Although elegant and capable, the Gordon-Keeble was no thoroughbred.  Using a square-tube space-frame purchased as part of the assets of a bankrupt company, it was clothed not in hand-formed aluminum but with the much cheaper fibreglass.  Using various bits and pieces taken from the parts-bins of many manufacturers, it was powered by a 327 cubic inch (5.3 litre) Chevrolet V8, essentially the same motor found in everything from Corvettes to pick-up trucks and while it may have lacked a pedigree, the purchase and the running costs were appreciably less than Maserati 5000 GT, one able to buy one for a fraction of the cost and, if the worst came to the worst, replace the engine and gearbox for less than the cost of an Italian cylinder head.

1965 Gordon-Keeble GK-1.

All but one of the one-hundred Gordon-Keeble GK-1s were built in England between 1964- 1967 by engineers once associated with the Peerless company, one of quite a few briefly to flourish during the 1950s producing low-volume runs of swoopy-looking fibreglass bodies atop custom frames, using a variety of power-plants.  It was a simpler time.  The genesis of the GK-1 was a request in 1959 from a US Air Force (USAF) pilot then stationed in England to fit a Peerless with a 283 cubic inch (4.6 litre) Chevrolet Corvette V8.  The concept, essentially the same as that Carol Shelby (1923-2012) famously and historically would pursue by mating the AC Ace with the Ford V8 to create the Cobra (1962-1967), so impressed the engineers they took a V8 Peerless to Carrozzeria Bertone in Turin, Italy where a steel body designed by Giorgetto Giugiaro was built, appearing on Bertone’s stand at the 1960 Geneva Motor Show where it was well received.

1964 Gordon-Keeble GK-1.

After long delays related to securing contractual relationships with external component suppliers, the show car was finished to a point close to the standard required for regular production and, after testing which convinced the engineers it was a commercially viable proposition, sent to Detroit as a proof-of-concept for General Motors to evaluate.  Suitably impressed, Chevrolet agreed to supply the Corvette engines and gearboxes for the first production run.  Visually, the GK-1 differed little from the prototype, but structurally and mechanically, there were changes.  Most obvious was the switch of the body construction from steel to fibreglass, the engineers’ preference for aluminum prohibitively expensive and the Corvette engine was the newer 327 cubic inch (5.3 litre) unit introduced in 1962.  Mechanically, the GK1 was ready and reliable and, with its space-frame, De Dion rear axle, four wheel disk brakes, twin fuel tanks and a host of internal fittings hinting at a connection with aviation, the specification was tempting.  Released in 1964, the critical response was overwhelmingly positive (although nobody had a good word for the steering) and demand seemed initially strong.

1965 Gordon-Keeble GK-1.

However, the back-shed curse, which afflicting many small-scale British manufacturers in the era, struck.  Under-capitalized, the company was unable to successfully to link its cash flow with the demands of external suppliers upon which production depended and, whatever the engineering prowess available, the accounting skills required successfully to operate as a trading organization were lacking; a retail price under Stg£3,000 was unrealistically low and inadequate to support the actual cost of production and development.  By 1965, with ninety GK1s having been sold, the company was perilously close to insolvent and was sold but the new owners proved no more adept than the old.  After struggling to complete another nine cars (one more was added to the total in 1971, assembled the previous year from the residual spare parts when the factory was liquidated), operations finally closed, hopes of a US-based revival proving abortive.

Clan Gordon emblem.

One quirky footnote in the Gordon-Keeble story was the creature on the marque’s badge: a tortoise.  That may seem a curious choice for a vehicle designed for high-speed but the beast ended up on the badge because of a boardroom dispute.  Bertone’s prototype at the 1960 Geneva Motor Show had featured a badge with a stag's head, the emblem of the Scottish Clan Gordon to which belonged one of the founders of Gordon-Keeble.  Because the clan’s motto was Bydand (abiding or remaining) which, in modern parlance translates as something like “durable, immortal, steadfast & everlasting”, it was thought appropriate for the GK-1, which did live up to the motto better than most, some ninety-two of the one-hundred said either to be in running condition or undergoing restoration.

Gordon-Keeble corporate logo.

However, because of the long delays before production began, it was necessary to seek bridging finance and this brought the inevitable managerial disputes and as a result, Mr Gordon left, contractually obliged to allow the project to continue using his name but he withdrew the right to use the clan emblem.  With everything else going on, that wasn’t given much thought until late 1963 when, with a debut finally close, a photo-shoot was arranged so brochures and other promotional material could be prepared.  At just the moment the absence was noticed, a tortoise happened to be wandering in the garden chosen as the backdrop and the meandering Testudinidae, unaware of the minor role it was about to play in UK corporate history, was picked up and placed on the hood (bonnet), everyone amused at the juxtaposition of one of nature’s slowest creations adorning one of mankind’s fastest.  The tortoise was returned to the flower-beds and adopted as the emblem, appearing on the escutcheon of every Gordon-Keeble.

Thursday, June 8, 2023

Superleggera

Superleggera (pronounced soo-per-lee-ghera)

(1) In automotive coach-building, a method of construction which combined a framework of thin steel tubes with aluminum outer panels, producing a lightweight structure.

(2) In recent years, a designation used as a model name to refer to a “lightweight” vehicle even if not a classic superleggera structure.

1935 (a patent for the technique issued in 1936):  From the Italian superleggera (super light) (feminine singular of superleggero), the construct being super- + leggero.  Super was from the Latin super-, from the Proto-Italic super, from the primitive Indo-European upér (over, above) which was cognate with the Ancient Greek πέρ (hupér) (above) and the Proto-Germanic uber (now familiar in English and translated as “over” although this doesn’t wholly convey the sense in Modern German).  Leggero (light in weight, slight, thin) was from the Old French legier, from the Vulgar Latin leviārius, from the Latin levis, from the Proto-Italic leɣis, from the primitive Indo-European hlengwih-, from hléngus, from hleng (lightweight). The cognates included the Sanskrit लघु (laghú), the Ancient Greek λφρός & λχ́ς (elaphrós & elakhús) and the Old English lēoht (the ultimate source of the English light).  Superleggera is a noun & adjective; the noun plural is superleggeras (or in the Italian the masculine plural is superleggeri, the feminine plural superleggere).

Carrozzeria Touring and superleggera

It was in 1926 that two Milanese lawyers discussed how bored they were with mundane, if lucrative, legal work and much preferred the exciting world of the automobile, the industry then something like that of IT in the early twenty-first century in that a critical mass of users had been established, growth was consistent and new ventures were coming and going amid a milieu of M&A (mergers & acquisitions).  The lawyers negotiated a controlling interest in Milan-based coachbuilder Carrozzeria Falco, changing the company’s name to Carrozzeria Touring.  Contracts to provide bodywork soon followed including from some of the industry’s major manufacturers including Citroën, Isotta Fraschini & Alfa Romeo and for some time they continued to adopt Falco’s methods which was an adaptation of the “Weymann” system which involved laying fabric over lightweight frames supported by a traditional separate chassis.  Touring produced elegant coachwork of a high quality and attracted the patronage of both Benito Mussolini (1883-1945; Duce (leader) & prime-minister of Italy 1922-1943) and Victor Emmanuel III (1869–1947; King of Italy 1900-1946) although perhaps more influential was the Queen who was often photographed alighting from one of Touring’s large cars, a more imposing sight than the exit of her diminutive husband.

1938 Alfa Romeo 8C-2900B LeMans with Touring Superleggera (left), a wrought-iron artwork installation based on the idea using the Volkswagen Beetle as a model (centre) and Lindsay Lohan with conventional (body-on-chassis) Beetle (Herbie: Fully Loaded (2005)).

Touring proved innovative in its use of strong, lightweight alloys to support the fabric skins and they enjoyed much success also in applying the technique to aircraft components such as wings and fuselages but during the 1930s with both the military and civilian airlines wanting to fly higher, faster, for longer and in all weather, the shift was beginning towards all-metal construction.  This was an organic evolution of the Weymann technique but the weight and other characteristics of sheet aluminum differed greatly from stretched-fabric and the system needed substantially to be re-engineered and it was the lessons learned from fabricating fuselages which led to Touring developing superleggera, the design patented in 1936.  The essence of superleggera was a skeleton of small diameter tubes which formed a body’s core shape, to which were attached thin aluminum-alloy panels which provided both aerodynamic form and strength.  Compared with earlier methods, as well as being inherently light, the method afforded great flexibility in fashioning shape and Touring took advantage of the properties of the metal to create both complex and flowing curves.  Some of their cars of the era did have lovely lines and in addition to the collaboration with Alfa Romeo which yielded sports cars, gran turismo machines and racing cars, the house attracted business from Lancia, Bianchi and others.

1938 Lancia Astura IV series coupé by Touring (left), 1949 Ferrari 166mm barchetta by Touring (centre), and 2014 Ducati 1199 Superleggera (right).

In the post war years, an era in which demand was high and regulations rare, the number of cars built according to the superleggera system increased as Touring licensed the use of its patent to others including Hundon in the US, Pegaso in Spain and Bristol, Aston Martin & Lagonda in England.  Bristol particularly took to the idea because of their long experience with airframes but perhaps the most influential stylistically was the 1948 Ferrari 166 MM Touring barchetta, a charismatic shape which provided a template which would remain recognizable in Ferraris for a quarter-century, the motif of the egg-crate grill still in use today.  While superleggera was unsuited to volume production, for the exclusive ranges at the upper end of the market it was ideal and both Lamborghini and Maseratis emerged built with the technique.  Although the two are sometimes confused because there are visual similarities under the skin, the space-frame method differs in that it can support the whole structural load whereas a superleggera is attached to an existing chassis.

1960 Aston Martin DB4 GT Zagato (left), 1961 Aston Martin DB4 Convertible (centre; the Volante designation wasn't then in use) and 1965 Aston Martin DB5 Saloon.

In the public mind, the most enduring connection was with Aston Martin which was granted a license to use the design and the Superleggera construction method at its Newport Pagnell plant for a fee of £9 for each of the first 500 bodies and £5 for each subsequent unit and the DB4 & DB5 (the latter made famous in the early James Bond films) were both built thus.  However, they represented something of the end of the era because governments were starting to pass laws which demanded road cars attain a certain degree of crash-worthiness, something the superleggera technique couldn’t be adapted conform to without sacrificing the very lightness which was its raison d'etre.  Additionally, the manufacturers were moving swiftly to replace body-on-frame with unit-construction.  Touring attempted to adapt to the changing environment by offering its services as a coach-builder for small, exclusive production runs and made the necessary capital investment but it had become crowded field, the supply of coach-builders exceeding the demand for their skills.  Touring ceased operations in 1966 but four decades on, there was an unexpected revival of the name, the company re-established as Carrozzeria Touring Superleggera, offering automotive design, engineering, coach-building, homologation services, non-automotive industrial design, and the restoration of historic vehicles.  A number of very expensive one-off and limited-production ventures for Maserati, Alfa Romeo and Bentley followed but what attracted most comment was the Sciàdipersia, shown in coupé form at the Geneva Motor Show in 2018, the cabriolet introduced the flowing year.  Based on the underpinnings of the Maserati Grantourismo, although owing no visual debt, it was very much in the tradition of the three Maserati 5000 GTs Touring built in 1959-1960, the first of which had been ordered by the Shah of Iran.  Superleggera however is now just a name with an illustrious history, the method of construction no longer in use and when used as a model designation, it now simply denotes what a literal translation of the Italian suggests: lightweight.

The original Maserati 5000 GT "Shah of Iran" by Touring (left; chassis #103-002) and Touring's Maserati Sciàdipersia in coupé form (centre; 2018) and roadster (right; 2019).

Vickers Wellingtons (B-series, Mark 1) during production, the geodesic structure visible, Brooklands, England, 1939.

There are obvious visual similarities between the classic superleggera method and the geodesic structure used in airframes and some buildings, most famously the “geodesic dome”.  The imperatives of both were strength both aim to create strong and lightweight structures, but they differ in their specific design and application.  As used in airframes, the geodesic structure consisted of a network of intersecting diagonal braces, creating a lattice framework which distributed loads as evenly as possible while providing a high strength-to-weight ratio.  This was of great significance in military airplanes used in combat because it enhanced their ability better to withstand damage better, the stresses distributed across the structure rather than being restricted to a limited area which could create a point-of-failure.  The geodesic framework was based on geometric principles which had been developed over centuries and typically employed hexagons & triangles to render a structure which was both rigid & light.  Superleggera construction differed in that it involves the creation of a lightweight tubular frame, covered with aluminum body panels of a thinness which wouldn’t have been possible with conventional engineering.  The attraction of the superleggera technique was the (relatively) minimalistic framework supported the skin, optimizing weight reduction without compromising strength.  So, structurally, the difference was the geodesic design used a network of intersecting braces to form a lattice, while the superleggera construction used a tubular frame covered with panels.

Saturday, May 13, 2023

Geodesic

Geodesic (pronounced jee-uh-des-ik or jee-uh-dee-sik)

(1) In spherical geometry, a segment of a great circle.

(2) In mathematics, a course allowing the parallel-transport of vectors along a course that causes tangent vectors to remain tangent vectors throughout that course (a straight curve, a line that is straight; the shortest line between two points on a specific surface).

1821: A back-formation from geodesy (a branch of science dealing with the measurement and representation of Earth, its gravitational field and geodynamic phenomena (polar motion, Earth tides, and crustal motion) in three-dimensional, time-varying space and with great (and "down-to-earth" as it were) practical application in surveying.  The adjectives geodesical & geodetic had first appeared in 1818 & 1819 respectively, both from geodetical which had been in use since the early seventeenth century.  All the forms are derive ultimately from the Ancient Greek γεωδαισία (geodaisía) from γῆ (geo) (earth) + δαιεῖν (daiesthai) ("to divide" or "to apportion") and the use in English was most influenced by the French géodésique, dating from 1815.  In general use, the word entered general use after 1953 when it was used of the "geodesic dome" (a structure built according to geodesic principles); despite the earlier use in wartime aircraft construction, the use there was only ever "engineer's slang".    Geodesic is a noun & adjective, geodesicity is a noun, geodesical is an adjective and geodesically is an adverb; the noun plural is geodesics.    The alternative adjectival form geodetic appeared in 1834 but fell from use by mid-century.  

Four-dimensional space-time.

Geodesic describes the curve that locally minimizes the distance between two points on any mathematically defined space, such as a curved manifold; essentially the path is the one of the most minimal curvature so, in non-curved three-dimensional space, the geodesic is a straight line.  Under Albert Einstein's (1879-1955) theory of general relativity (1915), the trajectory of a body with negligible mass on which only gravitational forces are acting (ie a free falling body), defines the geodesic in curved, four-dimensional spacetime.  Dictionaries and style guides seem to prefer “space-time” but scientists (and space nerds) like “spacetime” and because it was one of them who “invented it”, it seems polite to ignore the hyphen.  The term, a calque of the German Raumzeit (the construct in English being (obviously) space + time) first appeared in a paper by German mathematician Hermann Minkowski (1864–1909), published in the Philosophical Review.  The existence of the noun plural "spacetimes" does not imply something to do with the so-called multiverse (in cosmology, a hypothetical model in which simultaneously more than one universe exists) but rather that there are different space-times created in different places at different times.

General relativity fan girl Lindsay Lohan in optical illusion dress from the Autumn-Winter collection of interior designer Matthew Williamson (b 1971), illustrating an object causing the curvature of spacetime, Gift Global Gala, Four Seasons hotel, London, November 2014.  An “optical illusion dress” is one which uses a fabric print or other device to create the effect and differs from an “illusion dress” which is made with skin-tone fabrics placed to emulate the wearer’s own flesh.

In Einstein's theory of general relativity, gravity is treated not as a force as had been the historic understanding explained in the writings of Sir Isaac Newton (1642–1727) but rather as a curvature of spacetime caused by the presence of mass and (thus) energy.  The Sun, being a massive object, causes a (relatively) significant curvature in the surrounding spacetime and the Earth, as it moves through this curved spacetime, follows a path (a geodesic) which manifests as what appears to be an “orbit” around the Sun.  It is this curvature of spacetime that is perceived as the “gravitational pull” of the Sun on the Earth, keeping it in a (relatively) stable and predictable orbit.  Einsteinian physics supplanted Newtonian physics as the structural model of the universe and nothing has since been the same. 

Hull of Vickers R.100 Airship.

Sir Barnes Wallis (1887-1979) was an English engineer, best remembered as the inventor of the bouncing bomb used by the Royal Air Force in Operation Chastise (dubbed the "Dambusters" raid) to attack the Ruhr Valley dams during World War II and the big Tallboy (6 tonnes) and Grand Slam (10 tonnes) deep-penetration "earthquake" bombs.  Wallis had been working on the Admiralty’s R.100 airship when he visited the Blackburn aircraft factory and was surprised to find the primitive wood-and-canvas methods of the Great War era still in use, a notable contrast to the elegant and lightweight aluminum structure of airships.  He was soon recruited by Vickers to apply his knowledge to the new generation of fixed-wing aircraft which would use light alloy construction for the internal structure.  His early experience wasn’t encouraging, the first prototype torpedo bomber, which used light alloy wing spars inspired by the girder structure of R.100, breaking up mid-air during a test-flight.  Returning to the drawing board, Wallis designed a revolutionary structural system; instead of using beams supporting an external aerodynamic skin, he made the structural members form the aerodynamic shape itself.

The geodesic structure in an airframe.

The principle was that the members followed geodesic curves in the surface, the shortest distance between two points in the curved surface although he only ever referred to it in passing as geodetic; it wouldn’t be until later the label came generally to be applied to the concept.  As a piece of engineering, it worked superbly well, having the curves form two helices at right angles to one another, the geodetic members became mutually supporting, rendering the overall framework immensely strong as well as comparatively light.  Revolutionary too was the space efficiency; because the geodetic structure was all in the outer part of the airframe meant that the centre was a large empty space, ready to take payload or fuel and the inherent strength was soon proven.  While conducting the usual wing-loading stress tests to determine the breakage point, the test routine was abandoned because the wings couldn’t be broken by the test rig.

Vickers Wellseley.

The benefits inherent in the concept were soon demonstrated.  Vickers’ first geodesic aircraft, the Wellesley, entered service in 1937 and in 1938, three of them, making use of the massive fuel capacity the structure made possible, flew non-stop from Ismailia in Egypt to Darwin in Australia, setting a new world record distance of 7,158 miles (11,265 km), an absolute record which stood until broken in 1946 by a Boeing B-29 Superfortress; it remains to this day the record for a single-engined aircraft with a piston engine, and also for aircraft flying in formation.  While the Wellesleys were under construction, Wallis designed a larger twin-engined geodetic bomber which became the Vickers Wellington, the mainstay of the RAF’s Bomber Command until 1943 when the new generation of four-engined heavy bombers began to be supplied in in the volume needed to form a strategic force.  Despite that, the Wellington was still used in many roles and remained in production until after the end of hostilities.  Over eleven-thousand were built and it was the only British bomber to be in continuous production throughout the war.

Vickers Wellington fuselage internal detail.

The final aircraft of the type, with a more complex geodetic structure was a four-engined heavy bomber called the Windsor but testing established it didn’t offer significantly better performance than the heavies already in service, and the difficulties which would be caused by trying to replicate the servicing and repair infrastructure was thought too onerous so it never entered production.  Post-war, higher speeds and operating altitudes with the consequent need for pressurised cabins rendered the fabric-covered geodetics obsolete.

Aston Martin DB4 GT Zagato (one of 19 in the "Continuation Series", production of which began in 2019) during construction, an aluminium panel being attached to the superleggera frame, Aston Martin Works, Newport Pagnell, Buckinghamshire, England.

There are obvious visual similarities between the classic superleggera method and the geodesic structure used in airframes and some buildings, most famously the “geodesic dome”.  The imperatives of both were strength both aim to create strong and lightweight structures, but they differ in their specific design and application.  As used in airframes, the geodesic structure consisted of a network of intersecting diagonal braces, creating a lattice framework which distributed loads as evenly as possible while providing a high strength-to-weight ratio.  This was of great significance in military airplanes used in combat because it enhanced their ability better to withstand damage better, the stresses distributed across the structure rather than being restricted to a limited area which could create a point-of-failure.  The geodesic framework was based on geometric principles which had been developed over centuries and typically employed hexagons & triangles to render a structure which was both rigid & light.  Superleggera construction differed in that it involves the creation of a lightweight tubular frame, covered with aluminum body panels of a thinness which wouldn’t have been possible with conventional engineering.  The attraction of the superleggera technique was the (relatively) minimalistic framework supported the skin, optimizing weight reduction without compromising strength.  So, structurally, the difference was the geodesic design used a network of intersecting braces to form a lattice, while the superleggera construction used a tubular frame covered with panels.