Exoskeleton & Endoskeleton

Exoskeleton (pronounced ek-soh-skel-i-tn)

(1) In zoology, an external covering or integument, any hardened external structure, as the shells of crustaceans or the scales and plates of fishes and reptiles, especially when it is of the nature of bone.

(2) All hard parts, such as hair, teeth, and nails which develop from the ectoderm or mesoderm in vertebrates (generally used only in technical literature).

(3) A wearable robotic machine used for aided or augmented mobility.

1841: The construct was exo- + skeleton.  The prefix endo- was used as a word-forming element meaning "inside, within, internal.  It was from the Ancient Greek ἔνδον (éndon) (within; inner; internal) from the primitive Indo-European en-do- (an extended form of the root en (in)).  Skeleton was from the New Latin skeleton (bones, bony framework of the body), from the Ancient Greek skeleton soma (dried-up body, mummy, skeleton), from the neuter of σκελετός (skeletós) (dried up, withered, dried body (and as a noun: parched; mummy), from σκέλλω (skéllō & skellein) (dry, dry up, make dry, parch), from the primitive Indo-European (s)kelha- (to parch, wither); related was the Ancient Greek σκληρός (sklirós) (hard).  Exoskeleton is a noun; the noun plural is exoskeletons or exoskeleta.

Model Kate Upton (b 1992) making visible parts of her endoskeleton, Halloween Party, 2011.

Skelton was an early variant form.  The noun use of Greek skeletos passed into Late Latin as (sceletus), hence the French squelette and the rare English skelet (1560s), the Spanish esqueleto & the Italian scheletro.  The meaning "bare outline" was first recorded circa 1600; hence the term "skeleton crew" from 1778 used to describe minimal staffing, the skeleton key a similar allusion to some of a structure being removed.  The phrase "skeleton in the closet" (source of secret shame to a person, family or institution) is from 1812 and thought an adoption from the imagery in the fable Bluebeard (1697) by Charles Perrault (1628-1703). Exoskeleton was in 1841 coined by by English paleontologist Sir Richard Owen (1804–1892).  Exoskeleton has become more widely used in recent years because of the interest in fields such as engineering, robotics and medicine in using external structures, often to augment or replace human functions.  As early as the 1960s, the "exoskeleton look" became fashionable among architects who would no longer conceal features like plumbing pipes

Trilobites

Trilobite variants.

Trilobite (pronounced try-low-byte) translates literally as “three lobes".  Often casually referred to as bugs or sea-bugs, in taxonomy, all trilobites actually belong in the class of trilobite in the phylum arthropod and within the class are ten orders.  It’s not known how many species of trilobites existed but almost 21,000 have thus far been identified in the fossil record, their numbers and variety leading them to be regarded as one of history’s more successful animals.  They inhabited all the seas and oceans and endured some three-hundred million years, surviving several mass-extinction events.  Their long duration, their structure and living habits meant they became a common and frequently discovered fossil, noted since antiquity although the first attempt scientifically to classify one seems to have been by Wan Shizen of China who, in 1689 described trylobite pygidia (tails) as "batstones".  The first known scientific drawing was by Welsh botanist, the Reverend Edward Lhuyd (1660-1709) whose sketch of a trilobite was published in "The Philosophical Transactions of the Royal Society.  The drawing, now classified as being a Ogygiocarella debuchii, was then (not unreasonably), called the "flatfish".

Truly ancient, trilobites pre-date the Cambrian explosion (some 540 million years ago) and went extinct only towards the end of the Permian extinction event (some 250 million years ago) which ended the Paleozoic age which had lasted some 290 million years.  However, the earlier events took their toll, a few orders vanishing after the Ordovician event (some 445 million years ago) while the Devonian event (some 370 million years ago) removed all but one order, that last survivor dying out in the Permian event.  Why such a successful and prolific creature could not endure these extinctions remains a debate, the more popular theories including (1) environmental change happening with such rapidity there was no time for evolutionary adaptation and (2) the needed sources of nutrition vanishing because organisms lower in the food-chain went extinct.  All shared the same basic structure, having three lobes: a left pleural, a middle axial and a right pleural lobe, their bodies divided into a cephalon (dead), thorax (middle), and pygydium (tail).  Trilobites had a thick, protective exoskeleton which formed a hard calcite shell, something like that of the modern crab and is the reason for their frequency in the fossil record, the exoskeletons usually the only part to survive although, in the rare cases where certain surrounding conditions exist, traces of soft tissue such as antennae can survive fossilization.  As a trilobite grew, it molted its exoskeleton, and many of the fossils which exist are molted frames rather than dead creatures.

Before & after avian intrusion: 1952 Mercedes-Benz 300 SL (W194), Carrera Panamericana, Mexico, November 1952.

In nature, exoskeletons evolved over thousands of generations through the interplay of natural selection and adaptation to prevailing environmental conditions but with man-made objects such things, in cases of immediate need, can within hours be fashioned.  Returning to the circuits for the first time since the end of World War II (1939-1945), Mercedes-Benz had enjoyed immediate success with the new 300 SL (W194) race car which, despite being underpowered, proved its mettle with a combination of robustness, reliability and outstanding aerodynamics which both increased performance and improved fuel economy.  The W194, ten of which were built, is often referred to as “the first gullwing” (although the configuration had in 1939 been seen on a one-off Bugatti and was not uncommon in aviation and nautical use) but the distinctive doors were introduced only after those enforcing the regulations of sports car at Le Mans ruled the 300 SL’s original “doors” were no such things and were merely “elaborately framed windows”.  With re-designed doors fitted, the W194 promptly delivered the factory a 1-2 result in the 1952 24 hour endurance classic.

1952 Carrera Panamericana: The winning 300 SL in the factory museum.

Concluding things that year was the third Carrera Panamericana, a gruelling endurance event of eight stages over some 3,100 km (1,925 miles) between 19-23 November.  With typical thoroughness, the factory shipped three W194s along with a large support staff and all was going well until the lead car collided with a large bird (contemporary articles variously reporting the unfortunate creature as a vulture or buzzard) which smashed through the windscreen at an impact speed in excess of 215 km/h (135 mph), stunning the co-driver and leaving him bloodied.  Shook awake, he recovered and when the car reached the service point a new windscreen was fitted and, as a precaution against other vultures (or whatever) seeking vengeance, eight metal bars were fitted, the ad-hoc birdcage designed to keep them out, not in.  Without further avian “events”, the W194 repeated the result from Le Mans by finishing 1-2 and, fully restored, the winning car is part of the collection of the Mercedes-Benz Museum in Stuttgart.

1968 London-Sydney Marathon: The 1968 Porsche 911S which finished fourth (left) and after a full restoration (right).  A zoologist would insist this is only a "semiexoskeleton" on the basis of the partial coverage. 

As all in the Northern Hemisphere understand, in Australia, on land, sea & air, all the wildlife will try to kill you.  Noting this, when Porsche’s competition department prepared its three entries for the 1968 London-Sydney they limited their concern about sharks and crocodiles to a single paragraph in the drivers’ instruction sheets and decided the main threat to the cars were wandering “giant” kangaroos and low-flying wedge-tailed eagles (a bird with a wingspan wider even than Mexico’s vultures).  The first event of its type in the modern era, the 1968 London-Sydney Marathon spanned half the globe over a distance of 12,237 miles (16,934) and the route shows how times have changed, stages in Iran & Pakistan included; neither country now places many organizers of events would include in their itineraries but in 1968, kangaroos were still deemed more a threat than terrorism.  Accordingly, the factory designed a kind of exoskeleton, a robust external roll cage which essentially was the W194’s “birdcage” but “on steroids”.  As originally conceived, the structure had been of more modest proportions and while the final result may look like “overkill”, things were “beefed up” following one of the drivers writing off a rented VW Beetle after colliding with a kangaroo during pre-event testing in Australia.  Impressed by the extent of the damage, the engineers produced an impressively strong protective cage, content that whatever else might go wrong, it wouldn’t be a kangaroo which ended the venture.  Porsche 911S #58 finished fourth, victory going to a Hillman Hunter #75, one of the more improbable machines to win an international endurance event.

1968 London-Sydney Marathon: The winning 1968 Hillman Hunter (left) and restored 1967 Pakyan 1725 (right), the Iranian variants often noted for their additional bling.  Unlike the cautious Germans, most teams fitted only rudimentary additional protection against kangaroos and such; some ruefully later casting envious glances at Porsche's exoskeleton. 

In fairness, though an unlikely competition car, the Hillman Hunter (the “mainstream” model in the “Arrow” range which would sold also as “badge-engineered” Sunbeam, Singer & Humber variants) was a success in many countries, lasting in Europe from 1966 until 1979 although its most extraordinary longevity was achieved in the Islamic Republic of Iran.  In 1966, during the reign of Mohammad Reza Pahlavi (1919–1980; last Shah of Iran 1941-1979) assembly from CKD (completely knocked down) packs had begun with the car sold as the Paykan (پیکان, Romanized as Peykān and literally “Arrow”) and, unlike many things, it survived the 1979 revolution to continue to flourish under the rule of Grand Ayatollah Ruhollah Khomeini (1900-1989; Supreme Leader, Islamic Republic of Iran, 1979-1989), full local manufacture starting in 1985.  Although theologically uncompromising, there’s no record of the Imam having complained of the presence on his assembly lines of a product from شیطان کوچک (Sheytān-e Koochak) (the UK & Israel being “Little Satan” and the US شیطان بزرگ (Sheytān-e Bozorg) “Great Satan” although in the West the terms are often misunderstood because in flavour of Shia Islam practiced in Iran, Satan is a pathetic rather than fearsome figure).  When in 1979 Grand Ayatollah Ali Khamenei (1939-2026; Supreme Leader, Islamic Republic of Iran 1989-2026) became supreme leader, the Pakyan carried on and although production of the salon finally ended in 2005, the pick-up variant continued to be sold for another decade, the last not leaving the line until almost 50 years after the first Hunter was sold in the UK.  From the modest Hunter, the ayatollah's got their money's worth.

Exoskeleton cars

MVE Exocet (left) & Exomotive’s Exocet Sport V8 (right).

Exoskeleton vehicles are numerous on farms, mine-sites and such but rarely seen on public roads.  They do though have a niche for those who want something which sacrifices just about everything (aerodynamics, weather protection, doors etc) for the nimbleness only extreme light-weight can deliver.  An example is the MVE Exocet, released for public sale in 2010.  It’s an inventive approach to the kit-car concept and takes the classic front-engined, rear-wheel drive approach, based on Mazda’s Miata (the MX-5, introduced in 1989 and a kind of clone of the Lotus Elan of the 1960s but without the problems), the advantage with the Japanese platform being its unusual sub-frame which permits the removal of the body, leaving the engine, drive-train and suspension as a rolling assembly to be transplanted to the Exocet chassis.

Because of the light weight, even when using sensible four-cylinder engines the Exocet delivers high-performance but the Americans in particular can’t resist the idea that just about any car can be improved by the installation of a V8 and quite outlandish power to weight ratios are possible.  An indicative example of Exomotive’s Exocet Sport used a 525 horsepower (LS3) version of one of the later evolutions of the small-block Chevrolet V8 which, fully fueled, weighed in at 1690 lb (767 kg, the 2026 Formula 1 regulations set a minimum dry-weight (ie excluding fuel) of 768 kg).  Because it possible to buy, off the shelf (as a “crate” engine), V8 engines with about the same power as a F1 power-plant generates, although there was be something a weight penalty, the potential does exist to build a two-seater roadster with a similar power-to-weight ratio and there are jurisdictions which even allow such a thing to be registered for use on public roads.  Opinions would differ on whether such a build is a good idea but the little machines, if the V8 was tuned more for low and mid-range torque rather than ultimate power, would seem to have great potential in competitions such as short-course events and hill-climbs although the dubious aerodynamics would render it less suited to high-speed tracks.

Art and money: Porsche 934 (left) by Benedict Radcliffe (b 1976) sold for US$249,002 while Comedian (a banana duct-taped to the wall, right) by Maurizio Cattelan (b 1960) realized US$6.2 million.

The exoskeleton concept inspired English artist and sculptor Benedict Radcliffe to create a number of small scale tubular steel sculptures in the shape of cars including the Lancia Stratos (1973-1978), Lamborghini Countach (1974-1990) and Ferrari F40 (1987-1992), mostly powdered-coated in lurid colors.  Usually, they sell for several thousand US dollars but in early 2025, one in 1:1 scale in the shape of a Porsche 934 sold for US$249,002; in a nod to history, it was painted in the same fluro-orange used for the Jägermeister livery used for the race cars in 1979-1977 and rolled on period-correct centre-locking BBS wheels shod with Avon slick tires.  At that price, it was little different from what one would pay for a new Porsche 911 GT3, straight from the showroom floor.  Still, it’s less than the US$1.5 million which is typical of what’s been paid in recent years on the rare occasions a 934 is offered for sale.  Produced between 1976-1977, Porsche built 31 934s, simply for the purpose of creating a version of the 930 (the 911 Turbo, 1975-1978) which would comply with the FIA Group 4 (GT Cars) rules (the 935 was the companion Group 5 (Special Production Cars) project).  The art market cannot be assessed with any form of conventional metrics but in paying a quarter-million odd for a tubular structure, one gets quite a lot compared with the Italian visual artist Maurizio Cattelan’s Comedian, (a banana duct-taped to the wall); a couple of months earlier, at auction, it had gone under the hammer for US$6.2 million.

Endoskeleton (pronounced en-doh-skel-i-tn)

(1) In zoology, the internal skeleton or framework of the body of an animal (generally the bony or cartilaginous skeleton of vertebrates).  Certain invertebrates, such as sponges and echinoderms, also have endoskeletons.

(2) For most (non-technical) purposes, a synonym for skeleton.

1838: The construct was endo- + skeleton  The prefix exo- was used as a word forming element in words of Greek origin meaning "outer, outside, outer part" and was used from the mid-nineteenth century.  It was from the Ancient Greek ἔξω (éxō) (outer; external) and was related to ex (out of).  Endoskeleton is used almost exclusively in the biological sciences.  For most general purposes, it’s synonymous with skeleton which is the default assumption of use because it’s familiar from humans and most familiar animals.  Endoskeleton is a noun; the noun plural is endoskeletons or endoskeleta.

The nicely defined shoulder blade and ribcage definition of Lindsay Lohan's endoskeleton.

The word endoskeleton may not have been needed had all creatures on earth had “conventional” skeletons like humans, cats, dogs, fish and such; there would have been just “skeletons”.  Of course, architects and engineers likely would have been unable to resist coining “exoskeleton” there seems no better word to describe an externally-located superstructure.  Both an endoskeleton and exoskeleton are structural frameworks to some degree (sometimes wholly) supporting and shaping an organism’s body and which form an animal evolved to adopt was a product of history and environment.  That’s best illustrated by those with hard outer shell (really the ultimate exoskeleton) which functions as a kind of armor-plate.  Among man-made objects, both models are used and easily identified although exoskeletons (such as the futtocks in nautical design) probably are more common in anything with a “skin” including buildings, aircraft and ships.

Endoskeleton cars

The Birdcage: The Maserati Tipo 60/61 (chassis #2549).

Endoskeleton cars are far from uncommon but some make the concept more obvious than others.  The Maserati Tipo 60/61 (1959-1961) gained the nickname “Birdcage” (by which it’s almost always known) because observers were much taken with the delicacy of the construction.  By the late 1950s, space-frames had become familiar to race-car builders but they were usually robust-looking arrangements whereas Maserati had rendered an intricate latticework of some 200 chromoly steel tubes welded often in triangulated form in the points of highest stress, the design delivering both lightness and rigidity.

Mercedes-Benz 300 SLR (W196S, upper) & 300 SL (W198, lower).

One of the reasons the Maserati’s skeleton looked so delicate was that the space-frame had become associated with Teutonic-flavored construction like that used by Mercedes-Benz for its 300 SL & 300 SLR.  Both shared the same method of construction but despite the names and the the visual similarity between the two, there were few common components beyond the nuts, bolts & screws.  The 300 SL (W198; 1954-1963) was a road car while the SLR (W196S; 1955) was a lengthened version of the W196R Formula One Grand Prix car with a sexy body and an enlarged (though somewhat detuned) straight-eight engine.  Despite appearing much more substantial than the Maserati's birdcage, the German space-frame was remarkably light.

Blackwing

Blackwing (pronounced blak-wing)

(1) In zoology (mostly ornithology, entomology & ichthyology), a widely used descriptor of birds, insects, certain water-dwellers and the odd bat.

(2) As Blackwing 602, a pencil with a cult following, manufactured by the Eberhard Faber between 1934-1988, by Faber-Castell 1988 to 1994 and by Sanford 1994-1998.  A visually (though not technically) similar pencil has since 2012 been produced by Palomino.

(3) A high-performance V8 engine manufactured by the Cadillac division of General Motors (GM) between 2018-2020.  Cadillac continues to use Blackwing name for the some of its sedans.

1100s (originally of birds, first informally, later in formal taxonomy): The construct was black + wing.  Black (In the sense of the “color”) was from the Middle English blak, black & blake, from the Old English blæc (black, dark (also "ink”)), from the Proto-West Germanic blak, from the Proto-Germanic blakaz (burnt (and related to the Dutch blaken (to burn)), from the Low German blak & black (blackness, black paint, (black) ink), from the Old High German blah (black), which may be from the primitive Indo-European bhleg- (to burn, shine).  The forms may be compared with the Latin flagrāre (to burn), the Ancient Greek φλόξ (phlóx) (flame) and Sanskrit भर्ग (bharga) (radiance).  Black in this context was “a color” lacking hue and brightness, one which absorbs light without reflecting any of the rays composing it.  In the narrow technical sense, black is an absolute (absorbing light without reflecting any of the rays composing it) but in general use, as a descriptor or color, expressions of graduation or tincture are used, thus the comparative is blacker and the superlative blackest.  The usual synonyms are ebony, sable, inky, sooty, dusky & dark while the antonym is white.

Wing (in the sense used in “flight”) was from the twelfth century Middle English winge & wenge, from the Old Norse vængr (wing of a flying animal, wing of a building), from the Proto-Germanic wēingijaz, from the primitive Indo-European hweh- (to blow (thus the link with “wind”)).  It was cognate with the Old Danish wingæ (wing), the Norwegian & Swedish vinge (wing), the Old Norse vǣngr and the Icelandic vængur (wing).  It replaced the native Middle English fither, from the Old English fiþre, from the Proto-Germanic fiþriją (which merged with the Middle English fether (from the Old English feþer, from the Proto-Germanic feþrō)).  The original use was of birds but this quickly extended to things where a left-right distinction was useful such as architecture, sport and military formations (later extended to organizational structures in air forces).  Blackwing is a noun & adjective; the noun plural is blackwings.  In commercial use, as a registered trademark, an initial capital is used.

Quite why Cadillac (the premium brand of General Motors (GM) since 1909) chose the seemingly improbable “Blackwing” as a name for an engine and later the premium, high-performance versions (the V-Series) of its sedans (a now rare body-style in North America) is said to date to the very origin of the brand, more than a century earlier.  It was to recall the stylized black birds which appeared on the corporate crest first in 1902 (although not widely used until 2005 and trademarked in 1906).  That escutcheon was adopted as a tribute to the French explorer (some are less generous in their descriptions) Antoine Laumet de La Mothe, sieur de Cadillac (1658-1730) who in 1701 founded the settlement which became the city of Detroit.

Evolution of the Cadillac Crest: Antoine Laumet's original (and dubious) family crest (top left), A early Cadillac from 1905 (top centre), from a 1960 Coupe DeVille (top right), with the restored laurel wreath on the unfortunate vinyl roof of a 1968 Eldorado (bottom left), a post 2014 version without couronne & merelettes (bottom centre) and the current versions (bottom right), the black & white edition an illuminated badge created to mark the transition to electric propulsion; it's currently available as an option on petrol vehicles.  The illuminated grill badge was a trick long used by the English manufacturer Wolseley (1901-1975). 

Although of bourgeois origin and having departed France surreptitiously after “some unpleasantness”, shortly after arriving in the new world, Antoine Laumet re-invented himself, adopting a title of nobility named after the town of Cadillac in south-west France and in some histories, it wasn’t unusual for him to claim some vague descent from the royal line, a story common among many of Europe’s aristocratic families and his “family crest” was wholly his own invention.  Such things were possible then.  The Cadillac company modified the crest but retained the most distinctive elements: (1) The couronne (crown (from the Old French corone, from the Latin corōna, from the Ancient Greek κορώνη (korṓnē)) symbolized the six ancient courts of France; (2) The pearls (which appeared in various numbers on both the family & corporate versions) signified a family descended from the royal counts of Toulouse; (3) The shield denoted the military traditions of a noble family, the “warrior symbol” one of the most commonly used in heraldry while (4) The black birds were known as merlettes (an adaptation of the martin), mythical small birds without beaks or feet and never touching the ground, always in flight; they represent a constant striving for excellence, and when presented as a trio, referenced the Holy Trinity and thus a family’s adherence to Christianity.

A Cadillac Escalade driven by Lindsay Lohan receiving a parking infringement notice (US$70) for obstructing access to a fire hydrant, Los Angeles, September 2011.

The crest’s laurel wreath would remain until 2014 but the merelettes had been removed a decade earlier.The merelettes appeared often on the standards flown by knights during the late Medieval Christian Crusades staged to recapture the Holy Land but they didn’t disappear from the Cadillac crest in deference to sensibilities in the Middle East (a market of increasing value to GM).  Like the crown, the black birds were removed in 2000 as a part of a modernization exercise, the aim to achieve something “sharper and sleeker”, the more angular look of the new “Art and Science” philosophy of design.  “Art and Science” was from the class of slogans campaign directors of corporations and political parties adore because they mean nothing in particular while sounding like they must mean something.

Prestige by associative semiotics: Emblem of the 1971 HQ Statesman de Ville by GMH (General Motors-Holden's).

Cadillac over the years made may detail changes to the corporate crest and structurally, the most significant addition came in 1963 when an almost enclosing laurel wreath returned (it had been there in 1902 but was gone by 1908, returning for a run between 1916-1925) and it proved the most enduring design thus far, maintained until 2014.  It clearly had some cross-cultural appeal because in 1971 Holden (GM’s now defunct Australian outpost) made a point of issuing a press release informing the country “special permission” had been received from Detroit for them to borrow the wreath to surround the Holden crest on their new HQ Statesman de Ville, a car so special that nowhere on the thing did the word “Holden” appear, the same marketing trick Toyota would three decades on apply to the Lexus.

Black-winged Damselfly.

The elegant black-winged Damselfly, one of dozens of insects, birds, aquatic creatures and the odd bat known as the “black-winged” something.  One of some 150 species of Calopterygidae, the taxonomic name is Calopteryx maculata and the stylish little mosquito muncher is commonly found in North America, its other common name the ebony jewelwing.

Well GM understood the symbolic significance of the wreath.  The Cadillac 62 (1940-1964) had existed as an "entry level" model (ie lower cost) after the shuttering of the LaSalle (1927-1940) and when it was replaced by the Calais (1965-1976), one signifier of its place in the hierarchy was the corporate crest appearing wreathless, unlike the more expensive de Ville & Eldorado.  However, unlike the accessories, what has remained constant throughout are the emblem's core colors and, according to Cadillac, black against gold symbolizes riches and wisdom; red means boldness and prowess in action; silver denotes purity, virtue, plenty and charity while blue stand for knightly valor.  Behind the and crest, the background is platinum (a high-value metal) and the whole combination is said to have been influenced by Piet Mondrian (1872–1944), a Dutch artist noted for his work with color and geometric shapes.

Cadillac Blackwing V8.  It was a genuinely impressive piece of engineering but according to Road & Track magazine, Cadillac booked a US$16 million dollar loss against the project.    

Cadillac’s all aluminium Blackwing V8 was designed with an AMG-like specification which would once have seemed exotic to Cadillac owners.  Built in a single basic configuration, it featured a displacement of 4.2 litres (256 cubic inches), double overhead camshafts (DOHC), four valves per cylinder, cross-bolted main bearings and twin, intercooled turbochargers mounted in a “hot-V” arrangement (atop the block, between the cylinder banks) a layout which delivers improved responsiveness but, as BMW found, can bring its own problems.  Intended always to be exclusive to Cadillac’s lines (recalling GM’s divisional structure in happier times) it was in production less than two years because the collapse in demand for the models for which it was intended doomed its future; it was too expensive to produce to be used in other cars.  The early indications had however been hopeful, the initial run of 275 over-subscribed, a slightly detuned version accordingly rushed into production to meet demand.  In 2020, the Blackwing V8 was cancelled.

2025 Cadillac CT5-V Blackwing.

Repurposed, Blackwing however lives on at Cadillac, the company in 2021 appending applying the name to exclusive variants of its CT range sedans.  The CT5-V Blackwing is the last survivor of what once was a well-inhabited niche and although clearly an anachronism, demand still exists and although Cadillac has admitted this will be their last V8-powered sedan, in announcing the 2025 range they’ve made it clear the last days will be memorable.  In a nod to history, the company chose Le Mans in France to reveal details of the 2025 V-Series Blackwing “Special Editions”, honoring the “Le Monstre” and “Petit Pataud” Cadillacs which contested the 1950 24 hour endurance classic.  Each of those was a one-off (one especially so) but in 2025 there will be 101 copies of the Blackwing Le Monstre and 50 of the Petit Patauds.  The two are visually similar, the exteriors finished in Magnus Metal Frost matte paint, accented by Stormhawk Blue Carbon Fiber and Royal Blue brake callipers, the blue theme extened to the interior fittings.  Mechanically, the two are essentially stock, the Petit Pataud based on the CT4-V Blackwing powered by a twin-turbo 3.6 liter (223 cubic inch) V6 while the more alluring Le Monstre includes a supercharged 6.2-liter (376 cubic inch) V8.  For those who care about such things, although Mercedes-Benz AMG once offered rear-wheel-drive (RWD) 6.2 litre V8s, the Batwing offers the chance to enjoy the experience with a manual gearbox, something the Germans never did.  The Blackwings are also much cheaper and have about them an appealing brutishness, a quality Stuttgart’s engineers felt compelled to gloss a little.

Donald Trump (b 1946; POTUS 2017-2021 and since 2025), aged 30, with Cadillac Fleetwood, New York, 1976; the Fleetwoods of 1976 were the last to use the 500 cubic inch (8.2 litre) V8.

Roy Cohn was between 1973 and 1986 Mr Trump’s personal lawyer but also was influential in providing business advice and forming his world view, his instruction to Mr Trump that life was transactional, there being (1) people who would use him and (2) people he would use.  Famously, he also detailed the “three rule” for business and legal matters: (1) Attack, attack, attack; respond to any assault not with defense but a counter-attack, (2) Admit nothing, deny everything (this regardless of facts or available evidence) and (3) Always claim victory and never admit defeat; even if losing in court, claim a win.  Mr Trump of course for decades applied these rules in real estate, entertainment and other business ventures and later, used the same template in politics.  Some of Mr Cohn’s influence was more subtle; it was after engaging him as his attorney Mr Trump followed his example and purchased a personalized New York registration plate (DJT) for his limousine.

2025 Cadillac CT5-V Blackwing.  Compared with some of the atmospheric interiors in the Cadillacs of old, the Blackwing is disappointingly close to what one finds in a Chevrolet but for a number of reasons, creating something which is both attractive and lawful is not as easy as once it was.  For many, the sight of the stick-shift and a clutch pedal means all is forgiven.

In something which for most of the second half of the twentieth century have seemed improbable or unthinkable, between 2013-2026 it was possible to buy a Cadillac with a manual gearbox and a clutch pedal but not a Ferrari so configured.  Ferrari by 1976 had begun to flirt with automatic transmissions in their road cars (GM’s famously robust Turbo-Hydramatic 400) but until 2004, Cadillac hadn’t needed the clutch pedal apparatus in their factories since the last "Commercial Chassis" version of the 1953 Series 75 (among the Cadillac crowd the Cimarron (1982-1988) is never spoken of except in the phrase “the unpleasantness of 1982”).  However, by the early twenty-first century, the market for the cars Cadillac had perfected was shrinking fast so, noting the success of Mercedes-AMG and the M-Series BMWs, Cadillac entered the fray and the existence of the Chevrolet Corvette’s transmission in the corporate parts bin meant offering a manual gearbox was financially viable in a way it wasn’t for the Germans.  In the same decade, advances in hydraulics and electronics meant the earlier inefficiencies and technical disadvantages attached to automatic transmissions had been overcome to the point where no Ferrari with a manual transmission, however expertly driven, could match their performance and customers agreed, sales of manual cars dwindling until a swansong when the Ferrari California was released in 2008 with expectations some 5-10% of buyers would opt for a clutch pedal.  However between then and late 2011, wither two (2) or three (3) were ordered (the sources differ).

Between then and 2026, for Maranello, it was automatics (technically “automated manual transmissions”) all the way and that wasn’t anything dictatorial; had customer demand existed at a sustainable level, the factory would have continued to supply manual transmissions.  That has made the later manual versions of what typically were automatics collectables; on the rare occasions one is offered at auction, it attracts a premium and there's now an after-market converting Ferraris to open gate manuals.  It's said to cost up to US$40,000 depending on the model and, predictably, the most highly regarded are those converted using "verified factory parts".  The Cadillac Blackwing offered the nostalgic experience from the factory although the engineers admitted a slight performance penalty, buyers choosing the manual purely for the pleasure.  As early as 2024, rumors circulated that Ferrari might "revive" the manual gearbox as a niche option, probably on a model with the V6 engine because the torque and power generated by modern V8s & V12s would put too much strain on the clutch but, surprising many, in 2026, Ferrari announced there would be a run of 1,499 versions of the 12Cilindri with an eight-speed, open-gate "manuale" gearbox although the semantics in the press release did demand study, the transmission not a traditional, old-style device but one of the modern "automated manuals" with some clever engineering and software to emulate the experience (the gated “manueale mode” limited to controlling six of the eight installed ratios).  Being Ferrari, few were surprised to learn the model (and it was a separate model rather than an option) incurred a US$400,500 premium over the “standard” coupé but was attracted much comment was the wry observation of a few that the open gate's return was an “act of atonement” for having released the Luce, a five-door(!) EV (electric vehicle) that looked something like a large jellybean with wheels.  Usually, the announcement of a Ferrari rated at 1035 HP (horsepower) would have met general approval and the might have forgiven the extra doors but couldn't get over the ugliness.      

The quincunx induction system, the Cadillac Le Monstre and the 24 Heures du Mans, 1950

Living up to the name: The 1950 Cadillac Le Monstre.

The two Cadillacs which in 1950 raced at Le Mans were mechanically similar but visually, could have been from different planets.  The more conventional Petit Pataud was a Series 61 coupe with only minor modification and it gained its nickname (the translation “clumsy puppy” best captures the spirit) because to the French it looked a lumbering thing but, as its performance in the race would attest, Cadillac’s new 331 cubic inch (5.4 litre) V8 (which would grow to 429 cubic inches (7.0 litres) before it was retired in 1967) meant it was faster than it looked.  Underneath the second entrant (Le Monstre obviously needing no translation but used in the sense of “monstrosity” rather than “large”) there was also a Series 61 but the body had been replaced by something more obviously aerodynamic although few, then or now, would call it “conventionally attractive”.  Although Le Monstre seemed very much in the tradition of the “cucumber-shaped” Mercedes-Benz SSKL which had won the 1932 race at Berlin’s unique AVUS circuit, the lines were the result of testing a one twelfth (Uncia in the Latin) scale wooden model in a wind-tunnel used usually to optimize the shape of crop dusters and other slow-flying airplanes.  Presumably that explains the resemblance to a section of an airplane’s wing (a shape designed to encourage lift), something which would have been an issue had higher speeds been attained but even on the long (6 km (3.7 mile)) Mulsanne Straight, there was in 1950 enough power only to achieve around 210 km/h (130) mph although as a drag-reduction exercise it must have contributed to the 22 km/h (13 mph) advantage it enjoyed over Petit Pataud, something Le Monstre’s additional horsepower alone could not have done and remarkably, even with the minimalist aluminium skin it wasn’t much lighter than the standard-bodied coupe because this was no monocoque; the robust Cadillac chassis was retained with a tube-frame added to support the panels and provide the necessary torsional stiffness.

Le Monstre's 331 cubic inch V8 with its unusual (though not unique) five-carburetor induction system.  The layout (one in each corner, one in the centre) is a "quincunx", from the Latin quīncunx.

Some of the additional horsepower came from the novel "quincunx" induction system.  Le Monstre’s V8 was configured with five carburettors, the idea being that by use of progressive throttle-linkages, when ultimate performance wasn’t required the car would run on a single (central) carburettor, the other four summoned on demand and in endurance racing, improved fuel economy can be more valuable than additional power.  That’s essentially how most four-barrel carburettors worked, two venturi usually providing the feed with all four opened only at full throttle and Detroit would later refine the model by applying “méthode Le Monstre” to the triple carburettor systems many used between 1957-1971.  As far as is known, the only time a manufacturer flirted with the idea of a five carburetor engine was Rover which in the early 1960s was experimenting with a 2.5 (153 cubic inch) litre in-line five cylinder which was an enlargement of their 2.0 litre (122 cubic inch) four.  Fuel-injection was the obvious solution but the systems then were prohibitively expensive (for the market segment Rover was targeting) so the prototypes ended up with two carburettors feeding three cylinders and one the other two, an arrangement as difficult to keep in tune as it sounds.

Le Monstre ahead of Petit Pataud, Le Mans, 1950.  At the fall of the checkered flag, the positions were reversed.

Rover’s purchase of the aluminium 3.5 litre (214 cubic inch) V8 abandoned by GM (General Motors) meant the project was terminated and whatever the cylinder count, mass-produced fuel injection later made any configuration possible.  Five carburettors wasn’t actually the highest count seen in the pre fuel-injection era, Ferrari and Lamborghini both using six (done also by motorcycle manufacturers such as Honda and Benelli) and Moto-Guzzi in the 1950s fielded a 500 cm³ Grand-Prix bike with the memorable component count of 8 cylinders, 4 camshafts, 16 valves & 8 carburetors.  The early prototypes of Daimler’s exquisite hemi-head V8s (1959-1969) were also built with eight carburettors because the original design was based on a motorcycle power-plant, the reason why they were planned originally as air-cooled units. 

Motor racing is an unpredictable business and, despite all the effort lavished on Le Monstre, in the 1950 Le Mans 24 hour, it was the less ambitious Petit Pataud which did better, finishing a creditable tenth, the much modified roadster coming eleventh having lost many laps while being dug from the sand after an unfortunate excursion from the track.  Still, the results proved the power and reliability of Cadillac’s V8 and Europe took note: over the next quarter century a whole ecosystem would emerge, crafting high-priced trans-Atlantic hybrids which combined elegant European coachwork with cheap, powerful, reliable US V8s, the lucrative fun lasting until the first oil crisis began in 1973.

Perfection in a pencil: The Eberhard Faber Blackwing 602.  They were not cylindrical so, like a "carpenter's pencil", were less prone to rolling onto the floor.  

The Blackwing 602 remains fondly remembered by those who admire the perfect simplicity of the pencil.  Produced in the shape of a square ferrule (both pleasant to hold in one’s hand and less susceptible to rolling off the desk), it used a soft, dark graphite blend which required less pressure (the manufacturer claimed half but it’s not clear if this was science or “mere puffery”) to put what was wanted on paper.  To casual users, this may not sound significant but for those for whom pencilling was a full-time task (notably writers and artists), the advantages were considerable and the advertising claim “Half the Pressure, Twice the Speed” must have convinced one target market because the Blackwing 602 was a favourite of stenographers (a profession one of the early victims of the technological changes which have emerged in the wake of the transistor & microprocessor).  The Blackwing 602 was manufactured by Eberhard Faber between 1934-1988, by Faber-Castell (1988-1994) and by Sanford (1994-1998).  In 2012, after buying rights to the name, Palomino being production of a visually similar Blackwing but without quite replicating the graphite’s recipe.  Original Blackwing 602s are now a collectable and in perfect condition are advertised between US$50-100 although there was one recent outlier sale which benefited from a celebrity provenance.

Pencil porn.

Doyle’s in New York on 18 June 2024 conducted an auction of some items from the estate of US composer and lyricist Stephen Sondheim (1930–2021), attracting dealers, collectors & Sondheim devotees.  There was Lot 275: (Three blue boxes printed with "Eberhard Faber/Blackwing/Feathery-Smooth Pencils, two of the boxes complete with 12 pencils, one with 8 only (together 32 pencils).  Some wear to the boxes and drying of the erasers”, listed with a pre-sale estimate of US$600-800.  The hammer however fell at US$6,400; that’s US$200.00 per pencil, indicating the value of a celebrity connection so whoever set the pre-sale estimate (US$18.75-25.00 per pencil) obviously didn’t check eBay.

Propeller

Propeller (pronounced pruh-pel-er)

(1) A person or thing that propels.

(2) A device with a hub to which are attached evenly spaced & shaped radiating blades, rotating on a shaft to pitch against air or water to propel an aircraft, ship etc.

(3) A wind-driven (usually three-bladed) device that provides mechanical energy, as for driving an electric alternator in wind plants (not a universal use).

(4) A steamboat thus propelled; a screw steamer (now rare).

(5) In fishing, a spinnerbait.

1780: The construct was propel + -er and the original sense was “one who or that which that propels”, an agent noun from the verb propel.  The verb propel was a mid-fifteenth century form from the Middle English propellen (to drive away, expel), from the Latin propellere (push forward, drive forward, drive forth; move, impel), the construct being pro- (the prefix here use in the sense of “forward direction, forward movement”) + pellere (to push, drive), from the primitive Indo-European root pel- (to thrust, strike, drive).  The meaning “to drive onward, cause to move forward” emerged in the 1650s.  The –er suffix was from the Middle English –er & -ere, from the Old English -ere, from the Proto-Germanic -ārijaz, thought most likely to have been borrowed from the Latin –ārius where, as a suffix, it was used to form adjectives from nouns or numerals.  In English, the –er suffix, when added to a verb, created an agent noun: the person or thing that doing the action indicated by the root verb.   The use in English was reinforced by the synonymous but unrelated Old French –or & -eor (the Anglo-Norman variant -our), from the Latin -ātor & -tor, from the primitive Indo-European -tōr.  When appended to a noun, it created the noun denoting an occupation or describing the person whose occupation is the noun.  The alternative spelling propellor dates from the early days of aviation in the first years of the twentieth century and is now extinct.  The standard abbreviation is “prop”, the use noted from military aviation since 1914.  Propeller is a noun; the noun plural is propellers.

Although the concept was used in antiquity and inventors and others (most famously Leonardo da Vinci (1452–1519))  had for centuries experimented, the use of the word in mechanical engineering dates from 1809 and was from nautical design describing the application of a “device for moving vessels on or under the water”.  In aircraft design the theory of the use of “propeller” appears in papers and drawings in the 1840s (in what were then described as “flying machines”) and models were built which demonstrated a “proof of concept” although it would be decades before lightweight engines of sufficient power existed to allow experiments in aerodynamics and construction to be powered.  The first known rendering of an aircraft propeller in a recognizably modern form dates from 1853.  The modern propeller uses two or (usually) more twisted, airfoil-shaped blades mounted around a shaft which are spun to provide propulsion of a vehicle through water or air, or to cause fluid flow, as in a pump.  The lift generated by the spinning blades provides the force that propels the vehicle or the fluid although this lift does not of necessity have to induce an actual upward force; its direction is simply parallel to the rotating shaft.

Lindsay Lohan getting off the propeller driven (technically a turbo-prop) NAPA Shuttle, The Parent Trap (1998).

The term “to disembark” was borrowed from nautical use and of late "to deplane" has entered English which seems unnecessary but the companion “to disemplane” seems more absurd still; real people continue to “get on” and “get off” aircraft.

The terms “impeller” & “propeller” both describe devices which use various implantations of the “rotating blade(s) design and are used in mechanical systems to take advantage of the properties of fluid dynamics to harness specific energy for some purpose.  A propeller is a type of rotating device with blades designed to propel or move a fluid (typically a gas or a liquid) by generating thrust; they are most associated with marine vessels, aircraft and some industrial applications.  In aircraft, propellers can be attached to wing-mounted engines or mounted just about anywhere on a fuselage although historically a location at the front has been most common.  In marine applications, propellers have on specialized vessels been located to the sides of the hull but they almost always emerge at or close to the stern.  An impeller is a rotating component with blades or vanes (almost always enclosed in a housing), typically used for fluid or air distribution, such as a pump or a compressor, the primary purpose being to increase flow or pressure.  The classic impellers those in centrifugal pumps where they spin, creating a flow of fluid (liquid or air) by imparting centrifugal force to the substance; in practice, impellers such accelerate liquids are more common.

So an impeller & propeller do much the same thing, using blades to propel some form of fluid.  The use of different terms is helpful because in practice they are very different devices and the distinction that one is external and the other located within a housing is handy and the origin of that seems to lie in the construct of impeller which came first, dating from circa 1680 (as an agent noun from the verb impel) in the sense of “someone or something which impels”.  What the design of an impeller does is use the energy from the rotation to increase the flow or pressure of the fluid and it that it’s the reverse of a turbine, the rotation of which extracts energy from, and reduces the pressure of the flow.  Engineers also have a number of highly technical rules about what is and is not defined as an impeller base on the whether the entry and exit of the fluids occur axially or radially but it seemed impossible to construct such definitions as absolutes so for most the simpler distinctions are more helpful.  In engineering, impellers have been recorded as a machine or component name since 1836.

News Corp website 22 January 2024.  To refer to a jet engine’s nacelle as a propeller could (almost) be defended on the basis it’s the jet engine which “propels” the aircraft but this is more likely an example of (1) the decline in the quality of journalists and (2) what happens when there are no sub-editors to correct the mistakes.  In time, artificial intelligence (AI) should improve things.    

The verb impel dates from the early fifteenth century and was from the Middle English impellen, from the Latin impellere (to push, strike against; set in motion, drive forward, urge on), the construct an assimilated form of in- (into, in, on, upon), from the primitive Indo-European root en- (in) + pellere (to push, drive), from the primitive Indo-European root pel- (to thrust, strike, drive).  The construct of the Latin impellō was in- +‎ pellō (push, drive), from the Proto-Italic pelnō or pelnaō, a nasal-infix present derived from the primitive Indo-European pelh- (to drive, strike, thrust).  The Latin prefix –in could be appended to create a negative (un-, non-, not etc) but here was used as an intensifier, another possible meaning (in, within, inside) coincidental to the mechanical devices being usually mounted within housings.

Propellers and impellers both use blades (although those of the latter are often in the form of a single piece wither cast, molded, or (occasionally) forged.  Turbines also use blade-like parts but these are called vanes and an industry which seems unable to decide on terminology is the burgeoning business of wind-power; the huge rotating assemblies on wind turbines are referred to variously as vanes, blades or rotors.  Rotor blades are familiar for the use in helicopters which is essentially an airframe where a large-scale propeller sits atop the structure, pointing upwards and rather than “propeller blades”, the accepted term is “rotor blades”, the design of which permits both lift and directional thrust although some exotic multi-engined machines have rotors in housings which, to maximize performance, can themselves be rotated to operate as conventional propellers.

Supermarine Seafang (1946) with contra-rotating propellers.  The Seafang (1946-1947) was powered by the 37-litre (2240 cubic inch) V12 Rolls-Royce Griffon (1941-1955) and was the final evolution of the Spitfire (1938-1948) derived Seafire (1943-1947) and Spiteful (1944), the trio all designed for use on Royal Navy aircraft carriers, the series enjoying success despite the basic design being hampered by the narrow undercarriage which made landings a challenge (something corrected on the Spiteful & Seafang).  Series production of the Seafang was contemplated but eventually only 18 were built because the jet-powered de Havilland Sea Vampire (1945-1950) proved capable of carrier operations, surprising some at the Admiralty who doubted the jets could operate from anywhere but land.

Contra-rotating propellers (known also as coaxial contra-rotating propellers) were implemented on some World War II (1939-1945) aircraft to address several aerodynamic and performance challenges associated with the fitting of piston engines developing power well in excess of anything the designers had envisaged.  The attraction were many and included reducing the “torque Reaction”, the phenomenon in which the torque generated by a spinning propeller cause an aircraft to yaw in the opposite direction of the propeller's rotation.  Pilots had long been trained to counteract this by use of the rudder (especially during take-off and low-speed-flight) but as engine power rose and propeller blades became bigger, heavier and more numerous, the effect greatly was exaggerated.  On two or four-engined machines, the obvious solution was to have the blades on each wing rotate in opposite directions but on the most powerful of the single-engined fighters, the two units were mounted one behind the other and this had the benefit also of allowing the rear propeller to recover energy from the swirling airflow (the slipstream) generated by the forward.  That allowed designers to harness the greater power without increasing the diameter of the propellers, avoiding issues with ground clearance and supersonic tip speeds (one of the reasons the Soviet Air Force’s swept-wing (unusually in a propeller aircraft) Tupolev Tu-95 (Bear) bomber (in service 1956-1993) was so loud was because the propeller tips exceeded the speed of sound).  Had jet technology not emerged when it did, the contra-rotating propellers would have become more common, wartime adoption was limited by the complexity in assembly and additional maintenance demands.

A flight of Republic P-47D Thunderbolts with under-wing drop-tanks.

The propeller also influenced other aspects of the aircraft.  When the prototype Republic P-47 Thunderbolt (1941-1945) first took to the air, it was the largest, heaviest single-seat piston-engined fighter ever produced (a distinction it still enjoys today).  Even the early versions used an engine rated at 2000 horsepower (later this would rise to 2800) and to harness this output demanded a large propeller.  The 12 foot (3.7 m) diameter of this four-bladed monster meant the landing-gear had to be extraordinarily long and the only way it could be accommodated was to have them retract inward, otherwise the heavy wing armament (8 x .50 inch (12.7 mm) M2 Browning machine guns (425 rounds per gun)) wouldn’t have fitted.

Chrysler XI-2220 V16.  The splined shaft is where the propeller attaches.

With things like the Thunderbolt, the Hawker Tempest and the later Supermarine Spitfires (and its derivatives), the piston-engined fighter achieved its final evolutionary form, the jet engine offering a path to performance unattainable while the physics of propellers imposed limits.  However, had the use of the A-Bombs not ended the war in 1945, development of the propeller aircraft would have continued because the early jets lacked thrust and reliability as well as suffering a rate of fuel consumption which rendered them unsuitable for long-distance operations.  With the war against Japan envisaged as lasting well into 1946, development of faster, more powerful piston engines continued although, given the parlous state of the Japanese military, it’s dubious at least there was much of a rationale for this but the military industrial complex is a creature of inertia and Chrysler’s research had perfected a new aero-engine for the Thunderbolt.  The XI-2220 was a 2,220 cubic inch (36.4 litre) V16 which was rated at a basic 2450 horsepower with some 4000 hp available when tuned for wartime use but with the end of the conflict, all such developments were cancelled and attention switched to the brave new world of jets and swept wings.  Thus ended the era of the big propeller-driven fighters, the V16 stillborn, as was the other extraordinary aero-engine on the drawing board: Britain's 32-cylinder Napier-Sabre H-32 which was a scaled-up version of their H24.