Strangest Aircraft Ever Made

McDonnell XF-85 Goblin

This American experimental jet fighter from 1948 would probably be better classed as a guided cruise missile. Dropped from the bomb bay of a Convair B-36 bomber, the McDonnell XF-85 Goblin’s first generation jet engine was supposed to start in mid-air. And it did so in testing… at least most of the time.

The purpose behind this so-called “parasite fighter” was to drastically expand the range of fighter aircraft of the era. However, the concept was abandoned within a year in favor of cheaper mid-air refueling techniques. A system that was also much safer and far more efficient, though not nearly as exciting.

Rutan Model 202 Boomerang

This high-endurance sports plane was designed to maximize safety while performing crazy aerobatic stunts. While far from fuel efficient, its reliability and incredible climb/dive specs were rarely seen in a civilian aircraft. The asymmetrical Rutan Model 202 Boomerang only sat two, but they were in for a heck of a ride. This 1996 aircraft could still fly, just as well as a Cessna, if one of its twin engines failed.

  The Double Bubble D8

Image Courtesy of MIT/Aurora Flight Sciences
MIT’s D8 Series design hopes to be the new standard for passenger liners and transports in the near future. The iconic “double bubble” frame uses a modified tube and wing, which allows for much a wider fuselage than traditional aircraft. The ultra-low sweep wings cut down significantly on drag and weight, as well as generate extra lift. In addition, the engines sit aft of the fuselage and are fully embedded, which enhances the aircraft’s maneuverability considerably.

The D8 series aircraft should enter service in the early 2030s and could cruise at Mach 0.74, all while carrying at least 200 passengers out to a range of 3,000 nautical miles.

H-4 Hercules 2 “Spruce Goose”

A 200-ton monstrosity, the H-4 Hercules 2 was nicknamed the Spruce Goose because of its wooden frame (despite the fact that it was mostly made of birch). The heavy transport aircraft is the largest fixed-winged seaplane ever built and was designed by filmmaker and business magnate Howard Hughes. Only one was ever built; today it sits in a museum in Oregon.

Sky Voyage

 

The first of several personal aircraft on this list, the Sky Voyage is definitely one of the most ambitious and truly unique aircraft out there. As a combination airship and glider, the Sky Voyage family of aircraft could revolutionize sport flying as well as your daily commute.

The ultra-light ship can take off vertically by inflating the gasbag in an upright position. Once aloft, the aircraft is maneuvered through the wind and thermals like a glider, but also includes a backup hydrogen fuel cell, powered by a turbine engine. Some planned variants could be completely autonomous as well and would be able to stay airborne potentially for days.

NASA AD-1

Wind-tunnel experiments and computer models can only take you so far. To really grasp all the variables of a jagged object cutting through the atmosphere at high speed, sometimes you just have to strap up and dive in. That’s where NASA’s AD-1 comes in. This clever plane has a wing that could be readjusted a full 360 degrees horizontally to take flight testing to a whole new level. The tough wing could even pivot up to 60 degrees during flight without suffering major instability. Not too shabby for a plan built in 1979.

Convair F2Y Sea Dart

The Convair F2Y Sea Dart was an American seaplane fighter aircraft that takes off and lands using hydro-skis. This aircraft’s first flight was in 1953 and retired in 1957. This plane is the only seaplane to have exceeded the speed of sound.

Libellula

Image Courtesy of William Vanderson/Fox Photos/Getty Images
This twin-engine British experimental craft was primarily a military plane, though it had incredible potential for civilian purposes as well. First flown in 1945, it possessed incredible endurance and range for such a relatively lightweight transport/bomber. Uniquely, it was the first heavy bomber specifically designed to land on aircraft carriers. The Libellula was able to deliver a 2,000-pound payload out to 1,600 miles and cruise at 400 mph… quite an impressive list of specs for that day and age. As a civilian plane, it would have served as an incredibly powerful medium commuter plane.

Caproni Ca. 60

The Caproni Ca.60 Transaereo also known as the Noviplano or Capronissimo. It was a prototype of a large 9-wing flying boat. It was originally intended to be a 100 passenger transatlantic airliner. It had featured 8 engines and 3 sets of ripple wings. Its first flight was in 1921, and it was destroyed on its second flight.

X-57 Maxwell

 

Image Courtesy of Beutel, Allard, NASA
The X-57 Maxwell might look mundane, but this interesting aircraft is one of NASA’s premier technology demonstrators. As the flagship for the Scalable Convergent Electric Propulsion Technology Operations Research (SCEPTOR) project, the Maxwell will test some of the most farfetched aircraft designs out there.
Modified from an off-the-shelf Tecnam P2006T, the X-57 is an all-electric aircraft, with fourteen different EM motors driving propellers mounted on the wing leading edges.

The X-57 is NASA’s first X-plane in many years, but just the first and smallest of five in the New Horizons Initiative. The first flight is planned for 2017. All fourteen electric motors will be used during takeoff and landing, but only the outer two heavy engines will be employed during regular flight. The improved airflow over the wings caused by the additional motors generates much greater lift, which among other benefits allows for a narrower wing. The two-seat plane will have a range of approximately 100 miles (160 km) and a maximum flight time of about one hour. The X-57 should reduce the kilowatt energy required to power a light aircraft at 175 miles per hour (282 km/h) by five-fold.

Hiller X-18

The Hiller X-18 was a US Air Force funded experimental cargo transport aircraft made to be the first testbed for tilt wing and vertical/short takeoff and landing. Its first flight was in November 1959 and was scrapped in 1964.

Beriev Be-200 Seaplane

Image Courtesy of amphalon
This Russian behemoth is an incredibly versatile amphibious aircraft (1998). Whether used for search and rescue, maritime patrol, cargo or passenger hauling, the Beriev can take off and land from even fairly rough seas with up to 72 passengers. Where it really shines though is when serving as a fire-fighting water tanker. They can swoop down and scoop up 12 tons of water, all while flying at 90% of regular flight speed.

NASA’s GL-10 Greased Lightning

Greased Lightning (GL10) project 10 engine electric prototype remote control plane. Photo taken 8/14/14 by David C. Bowman
That odd-looking aircraft above is just a 50% scale, all-electric test bed for NASA’s groundbreaking GL-10. This diesel-electric tilt-wing helicopter seeks to address the shortcomings of current aircraft and take the technology to the next level. The next-generation of tilt-rotor aircraft will be much more reliable, fuel efficient and capable of hauling even heavier loads.

Setting it apart from contemporary designs, the GL-10’s wings and horizontal stabilizers also rotate with the fixed motors, which allows them to take off with a heavier payload. The current design calls for two heavy engines on the stabilizers and six smaller ones along the wingtips. In the future full-scale version, power will be provided by a pair of 6 kW (8 hp) diesel engines that will also continuously charge the lithium-ion batteries. The propellers on the wings’ leading edges generate high-speed airflow and increased lift even in low-velocity flight. All of which drastically improves pitch, roll, and yaw control during the critical transition phase from hover to forward flight, making the aircraft much safer.
The vastly improved VTOL capability of the GL-10 also reduces the need for elaborate ground support equipment. In addition, the new propellers are optimized for a low tip-speed, which markedly reduces engine noise. The current UAV variant is able to perform several vertical take-off and landings and maintain a loiter endurance of up to 24 hours in forward flight.

Mil V-12

The Mil V-12 is the largest helicopter ever built. Its first flight was an unsuccessful attempt in June 1967. It had a successful flight in July 1968, only to be cancelled.

Convair NB-36H Nuclear-Powered Plane

Image Courtesy of USAF
Billed as the ultimate fuel-efficient heavy lifter for both the private and military sectors, Convair’s NB-36 was powered by a 3-megawatt nuclear reactor. Theoretically capable of flying for months, its range was practically infinite. The aircraft’s uses would have been limited only by the operators’ imagination. A prototype was constructed quite easily, but the project was scrapped in the late 1950s due to its incredible cost and rather significant safety concerns. Still, this aircraft logged 215 flight hours, including 89 with the reactor running.

North American F-82 Twin Mustang

The North American F-82 Twin Mustang was the last American piston-engine fighter produced for the US Air Force. It was supposed to be used for World War 2, but the war ended before it was operational. Its first flight was in 1945 and retired in 1953.

B377PG – NASA’s Super Guppy Turbine Cargo Plane

Image Courtesy of NASA/DFRC
First flown in 1980, the B377PG “Pregnant Guppy” was one of the most unique transports ever constructed. This modified Boeing 377 is the perfect hauler for those gigantic, weirdly shaped payloads that need to be transported cross-country in a hurry. Originally commissioned by NASA to move components of the Apollo moon missions around, Guppies were still used extensively by the private sector for years after the program was canceled.

Short Skyvan SC-7

This early X plane flew from 1953 – 1956 and tested all sorts of technologies and techniques necessary for safe and sustain supersonic travel. The X-3’s unique frame started with an ultra slender, streamlined “needle nose” design and small trapezoidal wings. The hope was to craft the thinnest shape possible and cut down on drag when breaking the sound barrier, but that was just the most striking feature.

The extended nose was stuffed full of hi-tech test equipment and the partially concealed cockpit and windscreen alleviated the effects of “thermal thicket” conditions. The low aspect ratio, unswept wings were designed for high speed and later the Lockheed design team used data from the X-3 tests for the similar F-104 Starfighter wing design. Due to both engine and airframe problems, the partially completed second aircraft was canceled, and its components were used for spare parts. Despite the technical issues, the X-3 did manage to reach Mach 1.208 in a 30° dive in 1955.

Short Skyvan SC-7

The Short SC.7 Skyvan, nicknamed the “Flying Shoebox”, was a British 19-seat twin-turboprop aircraft manufactured by the Short Brothers in Belfast, Northern Ireland. It is used for short-haul freight and skydiving. Its first flight was in January 1963.

Goodyear Inflatable Plane

image courtesy of Goodyear
In the 1950s, Goodyear found themselves bored with tires and blimps and designed an inflatable, flyable aircraft. While the prototype handled itself little better than a powered glider, Goodyear tried hard to market the plane to the US Army. When the military found the powered balloon rather less than up to front-line service standards, Goodyear tried their best to market the plane to civilian hobbyists, with little success. Still, this is definitely one of the simplest and cheapest flying machines out there and might just make a comeback with modern technology.

Lockheed Martin P-791

The Lockheed Martin P-791 was an experimental hybrid airship that had its first flight in January 2006 at the US Air Force Plant 42 in Palmdale, CA.

De Lackner HZ-1 Aerocycle Flying Platform

This hybrid hovercraft/helicopter from 1954 was whipped up for the military but was perhaps the closest the world has come to a flying car. Able to carry an armed soldier on a reconnaissance mission over rugged terrain, surely it could have taken a single commuter to work or downtown on a shopping trip. While not incredibly reliable, the system was surprisingly fueled efficient and could have provided longer range than a motorcycle. However, a pair of major crashes grounded the craft and research dollars flowed to safer helicopters for the next few generations.  

Piaggio P180 Avanti

The Piaggio P.180 Avanti is an Italian executive transport aircraft that seats up to 9 people in a pressurized cabin. It can be flown by 1 or 2 pilots. Its first flight was in September 1986 and is still being produced today.

Lockheed Martin’s HALE-D Airship

 

Lockheed Martin’s latest airship concept, the HALE-D, is one of their most ambitious yet. The High Altitude Long Endurance Demonstrator borrows more from bird designs than traditional aircraft plans. The drone blimp is completely solar powered and can operate up to 60,000 feet. By cruising along jet streams and thermals while using its engines mostly to maintain position, the HALE-D is designed to stay airborne for months. Theoretically, even for years.

Once on station, the HALE-D could scan a radius of 600 miles with even more powerful sensors than surveillance satellites could carry. This relatively cheap alternative to satellites isn’t just limited to the spying roll. Many programs are active to convert the blimp into a weaponized drone “mothership.” Such a system could hover for vast periods of time over a conflict zone, collecting detailed intelligence the whole time, and then strike targets with unparalleled precision and accuracy.

Ames-Dryden (AD)-1 Oblique Wing

The NASA AD-1 was an aircraft and a flight test program conducted between 1979 and 1982 at the NASA Dryden Flight Research Center in Edwards California. Its first flight was in December 1979, and it retired in August 1982.

Northrop XB-35

The Northrop XB-35 was an experimental heavy bomber aircraft developed for the US Air Forces during World War 2. Its first flight was in June 1946. It was cancelled in 1949.

Dornier Do 31

Image Courtesy of amphalon
This odd West German experimental plane was one of the largest VTOL aircraft ever flown. First introduced in 1967, the Do-31 could haul more weight than even the modern MV-22 Osprey. The system wasn’t a tilt-rotor aircraft though. Instead, it required four engines to operate. Two Bristol Pegasus vectored-thrust turbofans in the inboard nacelles provided power in forward flight, and four Rolls-Royce RB162 on the outer nacelles generated lift for takeoff. While incredibly reliable, the aircraft was far from cost-efficient and never progressed beyond the prototype stage.

The Caspian Sea Monster, Korabl Maket

The Korabl Maket also known in English as the Caspian Sea Monster, was a Soviet experimental developed by the Central Hydrofoil Design Bureau in the 1960s. Its first flight was in October 1966. It was destroyed in 1980.

Northrop HL-10

image courtesy of NASA
The first of five space planes constructed for the Lifting Body Research Program of NASA from 1966 to 1970, the HL-10 showed the most promise. It would eventually contribute heavily to the Space Shuttle and influence all future space plane designs. Developing an aircraft that can safely and efficiently maneuver in atmosphere and vacuum is one of the hardest challenges for aerospace engineers.

The HL-10’s design offered a revolutionary low lift-over-drag ratio, designed specifically for reentry from space. While the program was canceled after a few years, the data gleaned from testing this “inverted airfoil” lifting body and delta airframe was invaluable to NASA, the military, and even civilian aviation. During a typical lifting body test flight, the B-52—with the research vehicle attached to the pylon mount on the right wing between the fuselage and inboard engine pod—flew to a height of about 45,000 feet (14,000 m) and a launch speed of about 450 mph (720 km/h). 

Edgley Optica

The Edgley EA-7 Optica is a British aircraft made for low-speed observation work. It is intended as an inexpensive alternative to helicopters. Its first flight was in December 1979.

Sikorsky X-Wing

The Sikorsky X-Wing was developed in the mid-1970s by the David W. Taylor Naval Ship Research and Development Center under DARPA funding. It was released in 1986 but never flew before the program was canceled in 1988.

Snecma Flying Coleoptere

he SNECMA C.450 Coléoptère was a French vertical takeoff and landing aircraft made by in the 1950s. Its first flight was in May 1959. On its 9th flight, the aircraft was destroyed due to insufficient instrumentation and a lack of visual benchmarks making the plane too inclined and too slow to maintain altitude.

Stipa-Caproni

The Stipa-Caproni or the Caproni Stipa, was an experimental Italian plane designed in 1932 by Luigi Stipa and built by Caproni. Its first flight was in October 1932.

Kaman K-Max

The Kaman K-Max is an American helicopter with intermeshing rotors. It is able to lift a payload of over 6,000 pounds. Its first flight was in December 1991. It was in production from 1991 to 2003. It went back into production in 2015.

X-36 Tailless Fighter Agility Research Aircraft

The McDonnell Douglas X-36 Tailless Fighter Agility Research Aircraft was an American prototype jet designed to fly without a traditional tail assembly. Its first flight was in May 1997. It is now retired.

The Airbus A300-600ST (Super Transporter) or Beluga

The Airbus A300-600ST also known as the Beluga is an aircraft modified to carry aircraft parts and oversized cargo. Its first flight was in September 1994. It was produced until 1999.

Blohm & Voss BV 141

The Blohm & Voss BV 141 was a German World War 2 tactical reconnaissance aircraft. Its first flight was in February 1938.

Nemuth Parasol

The Nemeth Parasol was tested at Miami University. This plane was a parasol wing above a conventional fuselage and tail. It was powered by a propeller in a tractor configuration.

Alexander Lippisch’s Aerodyne, A Wingless Experimental Aircraft

 

This funky barrel plane generated propulsion from two co-axial shrouded propellers. Built in 1968, the Dornier Aerodyne was the first, and only, “wingless” VTOL aircraft. Only a few test flights were ever completed in its two-month evaluation period, but all were made without incident. Still, Alexander Lippisch never found a buyer for the aircraft and eventually scrapped the program in 1971.

The flight principles behind the Aerodyne are rather simple. The combination of lift and thrust production in a single construction unit and the flow channel, i.e. a ducted fan. Flaps at the end of the fan divert the outflowing air to produce lift, thrust, or a combination of both. As a result, the Aerodyne could be steered and flown in the entire range between hovering and full-forward flight.

Northrup Tacit Blue

The Northrop Tacit Blue was a stealth demonstrator aircraft with a low probability of intercept radar. Its first flight was in February 1982 and was retired in 1985.

The Orlyonok

The A-90 Orlyonok was a Soviet ground effect vehicle that was designed by Rostislav Evgenievich Alexeyev of the Central Hydrofoil Design Bureau. Its first flight was in 1972. It was retired in 1993.

Curtiss-Wright VZ-7

The Curtiss-Wright VZ-7 also known as the VZ-7AP, was a vertical takeoff and landing quadrotor helicopter designed for the US Army. It was known as a “flying jeep”. Its first flight was in 1958 and was retired in 1960.

Hyper III

image courtesy of NASA
This massive lifting body drone, built at the NASA Flight Research Center in 1969, was far beyond its time. Most of the early technology involved is just now coming to fruition. The Hyper III was the pinnacle of the M2 lifting body program and equipped with a flat bottom and sides, as well as a simple straight wing with no control surfaces. The concept simulated a pop-out wing that had been proposed for a space traveling re-entry vehicle.

The Hyper III’s only control surfaces were a pair of fins with rudders canted at 40°, which also had hinged elevators on the horizontal surface. The Hyper III’s first and only flight took place on 12 December 1969, when it was launched from a helicopter at 10,000 feet. The aircraft glided 5 km, turned and then flew back before landing. After the three-minute flight, it was never flown again for budgetary reasons.

Lockheed XFV

The Lockheed XFV was also known as the Salmon, was an American experimental tail sitter prototype aircraft built in the 1950s. Its first flight was in June 1954.

Bartini Beriev VVA-14

Image Courtesy of Alex Beltyukov/Wikimedia Commons
This clever Soviet-era plane was a vertical take-off and landing amphibious aircraft, but it was also so much more than a simple seaplane. The Bartini Beriev VVA-14 Vertikal`no-Vzletayuschaya Amphibia employed a wing-in-ground-effect and could haul massive payloads. Designed as a high-performance, long endurance transport that could launch from water and cruise at high speed over long distances, it could also skim just above the sea surface and take advantage of aerodynamic ground effects. The VVA-14 was designed by Italian-born designer Robert Bartini in answer to a perceived requirement to destroy the United States Navy Polaris missile submarines, but only a few were ever made.

Vought V-173

The Vought V-173 also known as the Flying Pancake was an American experimental test aircraft built with the Vought XF5U ”Flying Flapjack” US Navy fighter ship program during World War 2. Its first flight was in November 1942 and it retired March 1947.

Proteus

image courtesy of NASA
This odd, tandem-wing research aircraft, built by Scaled Composites in 1998, was designed to serve as a temporary communications satellite. First flown in the late 1990s, the Scaled Composites Model 281 Proteus tested many technologies for use in high altitude telecommunications relays for the military and research institutions.

Due to its incredibly efficient airframe, the Proteus could cruise at 65,000 feet for over 18 hours. All at a fraction of the cost of a satellite in low earth orbit. Of course, the introduction of unmanned drones made such piloted aircraft unnecessarily expensive for long-endurance missions like these and the project was scrapped.

Scaled Composites White Knight Two

image courtesy of NASA
This ambitious research aircraft experimented with pivoting wings between 1979 and 1982, but a new version is in use today. The Scaled Composites Model 348 White Knight Two (WK2) is a jet-powered light cargo aircraft used to loft Virgin Galactic’s SpaceShipTwo spacecraft to launch altitude. Built by Scaled Composites as the first of a two-stage, suborbital-space manned launch system, the WK2 can trace its lineage all the way back to NASA’s Proteus experimental plane.

With its “open architecture” design available for anyone to modify, and explicit plans for multi-purpose use, the aircraft could also operate as a zero-g aircraft for passenger training or microgravity science flights, handle missions in high-altitude testing more generally, or be used to launch payloads other than SpaceShipTwo.

X-29 Forward Swept Wing Jet

Image Courtesy of NASA/DFRC
One of NASA’s coolest aircraft, this technology demonstrator (1984 – 1992) was way ahead of its time. The X-29 was known as a “three surface aircraft,” meaning it drew lift from the front canards, forward-swept wings, and aft strake control surfaces, rather than just traditional wings. Employing this three-surface longitudinal control significantly reduced trim and wave drag. To fight instability, the rear strakes provided trim whenever the plane’s center of gravity shifted. The net effect was to create one of the most ultra-maneuverable aircraft that ever existed.

This unique configuration, combined with a center of gravity well aft of the aerodynamic center, made the craft inherently unstable. Stability was provided by the computerized flight control system making 40 corrections per second. The flight control system was made up of three redundant digital computers backed up by three redundant analog computers; any of the three could fly it on its own, but the redundancy allowed them to check for errors. Each of the three systems could “vote” on their measurements so that if one malfunctioned it could be ignored. It was estimated that a total failure of the system was as unlikely as a mechanical failure in an airplane with a conventional arrangement.

Avro Canada VZ-9 Avrocar

image courtesy of USAF

This flying saucer was one of the world’s first successful vertical takeoff and landing (VTOL) aircraft. Developed as a secret U.S. military project in 1959, partly at the legendary Area 51 complex, the Avrocar was way ahead of its time. The propulsion system was intended to ride the Coandă effect and provide both lift and thrust from a single “turborotor.” This internal propeller sucked in air from underneath and blew out exhaust from the rim of the disk-shaped car/plane.

Originally designed as a fighter-like aircraft capable of very high speeds and altitudes, the project was repeatedly scaled back over time and the U.S. Air Force eventually abandoned it. Development was then taken up by the U.S. Army for a tactical combat aircraft requirement, a sort of high-performance helicopter. During flight testing, the Avrocar proved to have serious unresolved thrust and stability problems that seriously degraded its performance; subsequently, the project was canceled in September 1961.

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