Over the years, numerous unconventional aircraft designs have surfaced, with varying degrees of viability. Although many never advanced beyond the prototype phase, a few were constructed and operated for a period before being phased out for more reliable and practical options.
Listed below are some of the most unconventional aircraft ever to take flight. Notably, a significant portion of them originating during the Second World War.
PZL M-15 Belphegor
One of the oddest-looking aircraft on this list, the Polish PZL M-15 Belphegor was manufactured by WSK PZL-Mielec between 1976-81. It was designed for agricultural use and intended to be the successor to the Antonov An-2 and its variants, which also doubled as military transport and utility aircraft.
Three years after its first test flight in 1973, the M-15 began rolling off the production line – but not in droves. Despite initial estimates placing potential orders at over 3,000 units, only 175 were actually built. The reason for M-15’s short life? Its engine was very loud, it was unusually heavy and it could only travel 215 nautical miles. On top of all that, the aircraft was also expensive to produce.
If we’re being honest, the only interesting thing about the M-15 is that it was the world’s first (and only) jet agricultural aircraft.
Caproni Ca.60 Transaereo
Better known as the Noviplano, the Caproni Ca.60 Transaereo was a nine-wing flying boat designed by Giovanni Battista Caproni in the early 1920s. An absolute behemoth, this unusual passenger aircraft looked more like a half-constructed apartment building than something intended to take flight.
The Noviplano was intended to carry 100 passengers on transatlantic flights and, due to its size, featured eight engines. Only one was ever built, and it underwent a handful of test flights in 1921 on Lake Maggiore. On its second, it crashed into the water, breaking up upon impact. While plans were made to rebuild, these were later canceled due to the exorbitant costs associated with doing so.
McDonnell XF-85 Goblin
Conceived during WWII by McDonnell Aircraft, the XF-85 Goblin is without a doubt one of the strangest-looking fighters we’ve ever seen. During the conflict, the US Army Air Forces sent out requests for an aircraft that could deploy from the bomb bay of a Convair B-36 Peacemaker. The result was a parasite fighter that never entered production, let alone service. By the time it took its first flight, it was August 1948 and the war was long over.
When looking at the XF-85, you wouldn’t be wrong in assuming it’s missing its back half, as the fighter’s frame abruptly ends just behind the cockpit. We’re honestly having a hard time believing it could even fly properly, so we’re not surprised its development was canceled in 1949.
EL/M-2075 Phalcon
Resembling a clown’s nose, the Israeli EL/M-2075 Phalcon stands out as one of the most peculiar airborne early warning and control (AEW&C) active electronically scanned array radar systems ever created. Although still operational, its relevance has been increasingly challenged by the newer EL/W-2085 and EL/W-2090 systems.
Debuting in 1994, its purpose was to gather intelligence and conduct surveillance missions. Primarily designed for Boeing 707 aircraft, it can also be fitted onto 767s and 747s. Currently, only three are operational globally: one utilized by the Chilean Air Force and two by the Israeli Air Force.
LWS-6 Żubr
The second of two Polish aircraft featured on this list, the LWS-6 Żubr was a twin-engine medium bomber that came about a year prior to the outbreak of World War II. Originally conceived as a passenger airliner, this unique aircraft struggled to find much success, as it faced competition from the PZL.37 Łoś, another bomber introduced around the same period.
Primarily flown by the Polish Air Force for training purposes, the LWS-6 featured an outdated design that limited its use to non-combat roles. With just 20 units manufactured, most fell into the hands of the Red Army or the Luftwaffe, with the former seizing four during their invasion of Poland in September 1939.
Regrettably (or, perhaps, not), none survived the Second World War.
Lockheed XFV Salmon
That’s not a rocket you’re looking at – it’s the Lockheed XFV Salmon, an experimental aircraft designed to takeoff and land vertically. Intended to be flown by the US Navy, the plan was for the fighter to be used in the defense of convoys, but it never left the prototype phase. We’d like to say we can’t understand why, but we think the reason is pretty obvious in this instance.
Nicknamed the “pogo stick,” this unusual aircraft looks like its pilot didn’t know how to properly land it on the runway. While it underwent testing at Edwards Air Force Base, California in 1954 with the use of a temporary non-retractable undercarriage, the XFV Salmon was quickly shelved and the single flying prototype sent to Lakeland Linder International Airport in Florida, where it remains on display.
Transavia PL-12 Airtruk
Despite only 118 being built during its production run, the Transavia PL-12 Airtruk has developed a cult following, largely due to its cameo in Mad Max Beyond Thunderdome (1985). The Australian agricultural aircraft is most recognizable for its unusual design, which features a bulky cockpit that looks incredibly cramped and a long, narrow twin tail section.
The PL-12 came out of New Zealand’s need for a new aircraft whose sole job was cropdusting. Those typically used for the task were beginning to show their age, and while a handful of American designs had been imported, they were expensive to transport and maintain. We’re confused as to why this was the design that won out, but we’re happy it did, as its unusual appearance makes us incredibly happy.
Heinkel He 162 Volksjäger
Developed for use by the Luftwaffe during WWII, the Heinkel He 162 Volksjäger was a German fighter aircraft constructed primarily of wood. Not only that, its engine was mounted on top, making it appear as though it was giving its energy source a piggyback ride.
The He 162 was designed in just 90 days as a last ditch effort by the Germans to regain control of the skies. As such, it was riddled with issues, was relatively small and severely underarmed, with only two autocannons. Shortly after it entered service in April 1945, Germany surrendered to the Allied forces, meaning pilots only had to fly the unusual fighter for only a few weeks.
Tupolev Tu-144
Looking like a bird or a sad dog with its pointed droop nose, the Tupolev Tu-144 was a supersonic airliner produced by the Soviet Union between 1967-83. Notable for being the world’s first commercial supersonic transport aircraft, it could travel at speeds of up to 1,400 MPH, which is equivalent to Mach 2.
While reliability issues and the rising cost of fuel made the Tu-144’s use as a passenger aircraft short-lived, it was later adopted by NASA for supersonic research and the Soviet space program to train pilots tasked with flying the Buran spacecraft. In all, only 16 were ever produced, with just 102 commercial flights taking place.
Boeing X-32
The newest aircraft on this list, the Boeing X-32 was designed for use by the Joint Strike Fighter (JSF), only to lose out to the Lockheed Martin X-35. Despite taking its first flight in 2000, the demonstrator’s origins date back to 1993, when the Defense Advanced Research Projects Agency (DARPA) launched the Common Affordable Lightweight Fighter (CALF) project. A number of concepts were presented, including the X-32.
What makes the aircraft immediately distinguishable (and unusual) is its wide body and small wingspan, making you question how it could possibly remain stable while in the air. Following its being snubbed, the flight tested prototype of the X-32 was moved to the National Museum of the US Air Force at Wright-Patterson Air Force Base, Ohio, where it deteriorated after long-term exposure to the elements.
Thankfully, it has since been restored, meaning visitors can once again catch a glimpse of one of Boeing’s most unusual aircrafts.
Blohm & Voss BV 141
The Blohm & Voss BV 141 was a German reconnaissance aircraft and light bomber developed in the lead up to WWII. You’ll likely do a double take upon looking at a picture of it, as its unusual asymmetrical design is definitely not something you typically see.
Designed by Richard Vogt, the BV 141 should have been riddled with issues, including the risk of rolling due to one side being longer (and presumably heavier) than the other. However, it’s said to have performed relatively well, thanks to the design of its wings. Despite this, the German Air Ministry (Reichsluftfahrtministerium) believed it to be underpowered and it wasn’t designated for full service.
Bréguet 761/763/765 Deux-Ponts
While multi-level airliners are commonplace today, back in the 1940s and ’50s, they were still relatively new. As such, their designs were pretty…Questionable. Take the Bréguet 761/763/765 Deux-Ponts, for example. Introduced in 1953, it’s pretty much the definition of unusual – and ugly.
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Flying in both a civilian and military capacity, the double-decker aircraft proved to be effective and relatively safe, with the French Air Force using it to move personnel and materials to areas in the Pacific where nuclear testing was underway. Despite many viewing it favorably, it sadly wasn’t destined for long-term service and was retired in 1971. Only 20 were ever produced.