Top 10: The strangest Aircraft ever made

Sometimes successful, sometimes abject failures, the teams behind these fascinating feats of engineering should all be applauded for their original thinking. Let’s meet ten gloriously weird aircraft:

The story of this deeply weird flying machine starts in the Soviet Union in 1989. Alexander Filimonov wanted to build an aircraft that could operate from the Arctic, Siberia and the far east of Russia without purpose-built airfields. Though airfields may be lacking in these regions, there are numerous natural flat airstrips in the form of lakes, rivers, marshes and fields.

Even a rugged seaplane will struggle with marshes, and a helicopter or aeroplane needs special adaption (and a brave pilot) to operate from very thick snow or long grass. As the company's website notes, "For example, the well-known Russian An-2 aircraft has three changeable take-off and landing devices: wheel, ski and hydrofloat. The first two require runways."

So how could an aircraft deliver cargo or people to such austere locations? Filimonov believed the answer was to combine the advantages of a 'wing-in-ground' effect ekranoplan with a conventional aeroplane. The wing-in-ground effect is kind of ‘floating’ that occurs when a winged aircraft is very near a surface and air vortices are ‘squashed’.

The result is a strange hybrid, with a horizontal ducted helicopter-like fan, a hovercraft-like 'skirted doughnut' – and pusher engines and wings. Here was a machine that could make very short take-off from extreme terrain and do it in terrible weather conditions. Funding was never found for this extremely unusual project.

In the 1930s, Charles H Zimmerman advocated the ‘discoidal’ aircraft which has a pancake-shaped fuselage acting as a lifting surface. Zimmerman had worked on NACA’s (later renamed NASA) early wind tunnels. He wanted to produce a circular VTOL aircraft capable of flights at unbeatable speeds and altitudes, and able to hover like a helicopter. This proved overly ambitious with contemporary technology but earned Zimmerman a prestigious NACA award.

Zimmerman believed that discoidal aircraft could be capable of near vertical take-off and landings. They also promised excellent manoeuvrability, high speed and great structural strength. The concept, nicknamed the ‘Zimmer Skimmer’, was radical and unlikely- so Zimmerman set about demonstrating its veracity with a series of prototypes for both himself and the Vought company.

The V-173 flew in 1942. Soon locals were reporting UFOs, even if the term didn’t exist yet (‘UFO’ was coined in 1953 by the USAF). Aviation pioneer Charles Lindbergh flew the type and found it handled extremely well. Initial problems were centred more around the propulsion system, which used a complex geared system to route power to the propellers from the engine than the novel aerodynamic configuration.

One propulsion failure led to a dramatic emergency landing on a beach. As the aircraft landed the pilot spotted two utterly bewildered bathers in the aircraft’s path. Full braking effect was applied, resulting in the aircraft somersaulting over on itself. Thanks to the aircraft’s immense strength both the pilot and aircraft emerged unscathed.

Before the V-173 had flown, Zimmerman was working on its weaponised successor, the Vought XF5U ‘Flying Flapjack’ for the US Navy. Fast, agile, well-armed (six ‘50 cals’ or four 20mm cannons) and with a tiny take-off run the aircraft was a tantalising prospect as a carrier fighter.

The geared propulsion system again proved troublesome, as did the repeated operation of piston engines and very large propellers at very high angles of attack. Development dragged on, and the war ended.

By 1947 the Vought XF5U-1 was finally ready to fly. But propellers were passé, Vought was busy moving to Dallas and the ‘Pancake’ had run out of luck. Unusually, the US Navy ordered the aircraft be reduced to scrap.

Vought’s chief test pilot Boone Guyton had been looking forward to flying the aeroplane and was extremely upset by this wanton destruction. He tried to physically stop the wrecking crew, but failed. The wrecking ball took a long time to destroy the immensely tough airframe, but eventually succeeded.

Looking like it flew straight through a wind tunnel taking the fan with it, the first all-composite aircraft was the Mississippi State University XV-11 MARVEL. MARVEL is a backronym standing for ‘Mississippi Aerophysics Research Vehicle with Extended Latitude’.

The aircraft was built to continue research for the military into boundary layer control, an effort that had been ongoing since the 1950s. Accordingly, the MARVEL employed a blower driven by the engine to draw suction through more than one million tiny holes in the wings and fuselage.

The aircraft also spurned conventional flaps in favour of wing warping to deflect the wing trailing edges. So far, so weird, but the good people of the Department of Astrophysics and Aerospace Engineering at the Mississippi State University weren’t stopping there.

There was also a ‘Pantobase’ or ‘rollerboot’ undercarriage with tandem wheels fitted within two sprung wooden pontoons which were intended to allow operations from rough surfaces or water. The ducted pusher propeller concept returned with little success in the Edgely Optica and RFB Fantrainer.

If you’re a multimillionaire and you want a new private jet, you have many obvious if slightly unadventurous choices. Textron, Dassault, Bombardier, Gulfstream or Beechcraft will be happy to sell you a sleek, safe and refined jet that will perfectly fit any brief. If you’re feeling a bit quirky, you might even take a look at Pilatus and their PC-12, or maybe the stiletto-inspired HondaJet.

But if you’re not just a run of the mill multimillionaire, you’ll want an aircraft which will stand out on the apron when you fly into Samedan for a spot of snow polo. In that case, there’s only really one choice: The weird and beautiful Piaggio Avanti P.180.

With the P.180, the turboprop engine and its propellers point backwards, the third, anhedral (anhedral means the tip of a wing or surface is lower than where it meets the fuselage) lifting surface at the front, the wing-shaped fuselage, the T-tail and massive delta fin strakes, the scimitar-shaped blades in the latest EVO version.

Perhaps it’s not surprising that the Avanti is so different, because Piaggio has a history of making decisions against the grain. First, there was the P.2, an aerodynamically clean monocoque, low-wing monoplane which flew in 1923, when most other manufacturers were busy bracing the wings of their biplanes with wires.

But Piaggio’s place in the heritage of weird planes is assured by the P.7, an amphibian racer built to compete in the famous 1929 Schneider Cup Race, which forced designers and manufacturers to make ever more low-drag designs and liquid-cooled engines, inspiring the Spitfire and the P-51 Mustang. The Piaggio P.180 is the fastest propeller-driven aircraft ever flown with an astonishing top speed of 576.3 mph.

With some notable exceptions, the West tended to believe that the world should adapt to support its aeroplanes, whereas the Soviet Union believed the aeroplane should adapt to function in the world as it is. The result was the West ended up with big clean airbases and the Soviet Union ended up with rugged, if relatively unsophisticated, aircraft.

The Antonov An-14 was a small tough short take-off and landing transport. It was intended to replace the hugely popular An-2 biplane, the only problem being that the An-2 was still doing its job very well and didn't need replacing. Antonov gave up after only 332 units - which is small potatoes compared to the 18,000-plus An-2s.

Perhaps as a punishment for lack of success, the Antonov Design Bureau used the unlucky type for multiple experimental purposes. On January 22, 1983, one An-14Sh, took to the sky with the indignity of a hovercraft undercarriage. In flight the cushion skirt retracted into the large ventral pod).

This would have allowed the An-14Sh to have taken off or landed from any flat (or almost flat) surface from rivers to bumpy fields. The huge drag and reduction in range and payload were unacceptable and the project did not carry only beyond the prototype stage though the idea may have influenced the later Bella 1.

Robert ‘Ludvigovich’ Bartini was an aristocratic Hungarian-born aircraft designer. The Italian Communist Party sent him to the USSR following the Fascist takeover of Italy. The communist party intended that he would bring modern Italian know-how to the Soviet aviation industry to aid its fight against fascism.

Being an aircraft designer was an extremely dangerous occupation in Stalin’s terror state, and being a foreign aircraft designer was even more perilous. In 1938 Bartini began an eight-year prison sentence. Despite spending the second world war imprisoned, he still did a huge amount of design work, notably on the Tu-2 bomber. Bartini also proposed the A-57, a long-range strategic bomber that could land on water and refuel by submarine.

He became one of the most important Soviet aircraft designers, and survived to design the exceptionally unusual VVA-14, designed to counter the threat of Polaris missile submarines. This was a wing-in-ground-effect vehicle, a type of aircraft which sits on the recirculated air that forms beneath wings at extremely low altitudes. Capable of taking off from land or water, the vehicle could fly far faster than any boat at ultra low-level while carry large loads. It could also fly at higher altitudes as a true aeroplane.

In collaboration with the Beriev Design Bureau, Bartini planned to develop the prototype VVA-14 in three phases. The initial M1 was to be an aerodynamics and technology testbed. The M2 would have a battery of 12 Rybinsk RD-36-lift engines to give full VTOL capability, and was to be fitted with one of the world’s first fly-by-wire flight control systems.

Bartini died in 1974 and with him the momentum that drove the project. Like all Ekranoplans, being neither fish nor fowl no one quite knew what to do it with it and the VVA-14 never entered service.

In 1928, the Blériot company created a modern airliner, that looked – and still looks – like nothing else, the Blériot 125. The specifications called for a passenger aircraft that could carry between ten and twelve passengers over a range of 1000 kilometres. The aircraft was distinguished by the presence of two passenger cabins and a central cockpit, making it a double-beam aircraft, with two huge pods.

The 125 was powered by two Hispano-Suiza 12HBr inline engines installed in a push-pull configuration that was rather unusual for the time. It was at the Grand Palais Air Show in Paris in 1930 that the aircraft was presented to the public for the first time.

Although there was no aesthetic standard for the perfect design of an airliner as there is today, visitors were surprised by its strange configuration. An American press correspondent cruelly called the twin-engine aircraft a “Flying Joke” – despite his complete lack of knowledge of the aircraft’s performance in the air.

The ‘Flying Joke’ actually had relatively good flying characteristics and was fairly easy to fly. However, its single radiator was insufficient and its thick, asymmetrical, double-beam wing proved rather draggy. But it was not these minor shortcomings, but its unorthodox aesthetics that was to draw the most criticism. Nobody, from the civilian or military world, was interested in ordering this promising machine.

French engineer René Louis Riout built his first flapping wing aircraft in 1913, the DuBois-Riout. He managed to get the machine off the ground in 1916, but it crashed almost immediately and was condemned to join the eternally rolling montage of disintegrating early flying machines usually accompanied by jaunty comical piano music. Undeterred, Réné Riout continued to develop concepts for flapping-wing aircraft (ornithopters) .

He built larger and larger models until one day he proposed his ideas to the Service Technique de l’Aéronautique (Aeronautics Technical Service, a state body coordinating aeronautical efforts, founded in 1916). The STAé was interested in the engineer’s strange ideas and agreed to the development of an experimental prototype.

And so, the Riout 102T Alerion was born (or hatched). Its fuselage was made of tubular steel and covered with aluminium. The closed cockpit was located at the very front of the machine, in the nose and the engine, a small V-twin engine was installed behind the pilot and the attachment point of the four flapping wings.

The aircraft was equipped with four small retractable wheels and four wings operating in pairs. By early 1938, construction of the Alerion was completed and it was moved to Chalais-Meudon (an aeronautical research and development centre to the southwest of Paris).

Wind tunnel testing began with the wings stationary, then later flapping, before the final stage of deformation was tested (it is this deformation that produces thrust to propel the aircraft). The wings gave way under the rigours of the wind tunnel combined with the violence of the flapping. The machine was not repaired – and it never flew.

Seemingly a business jet designed by H. R. Giger to take him to the depths of Hieronymus Bosch’s hell, let’s meet the utterly unlikely Gyroptère. Engineers Papin and Rouilly created a sort-of helicopter whose flight technique was directly inspired by the fall of the samaras, the winged seeds of the sycamore tree.

It consisted of a single rotating 17-metre-long blade driven by a tip-jet of compressed air, produced by an 80-horsepower Rhone rotary engine driving a compressor. The engine also served, as a counterweight to the blade. The pilot sat at the centre of gravity in a small gondola which was stabilised from the rotation of the blade by a second jet of compressed air.

Prayers would seem mandatory for the test pilot strapped to this massive mechanical spinning Edwardian sword. The configuration allowed, in (the quite likely) case of failure, the pilot to gently lower the machine back to the surface of the water…at least in theory.

A prototype was built in 1913, but tests were delayed by both a troubled development and the outbreak of the first world war, and the machine did not make its first attempt to take off until March 1915, from the Cercey reservoir in France. After starting the engine, the canopy began to turn, and the machine took off and left the water for a short time before becoming violently unstable. The weird craft hit the surface of the water and sank.

Sure of their machine, despite unconvinced military observers, Papin and Rouilly persisted in hunting for finance for this bizarre project until they finally gave up in 1936.

Though unsuccessful, the Gyroptère was the first rotary craft to use tip-jets without any mechanical link between the rotor and the engine. It was not until the 1950s with the arrival of the SNCASO SO.1221 ‘Djinn’, that the principle of tip-jets was to find application on a production aircraft. The overall Gyroptère concept was a technological cul-de-sac, but a fascinating vision of another universe where the giant mechanical tomahawk was a viable form of transport.

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