The Pregnant Guppy was the first of the Guppy line of aircraft produced by Aero Spacelines. The design inspired other later designs, such as the jet-powered Airbus Beluga and Boeing Dreamlifter.

In 1960, U.S. airlines were disposing of their obsolete piston-engined Boeing 377 Stratocruisers in favor of the newer jet-engined airliners. NASA was finding that barge transport of their increasingly large space program components from manufacturers on the West Coast to test and launch sites on the East Coast was slow and expensive. Aircraft broker Leo Mansdorf was stockpiling surplus Stratocruisers at Van Nuys prior to resale, and ex-USAF pilot John M. Conroy realized the potential of these aircraft to transport the large but relatively light rocket components.

Conroy presented his plans for an extensively modified Stratocruiser to NASA, where an official commented that the bloated aircraft resembled a pregnant guppy. Although NASA was lukewarm on the concept, Conroy mortgaged his house and founded Aero Spacelines International to build and operate the concept aircraft.

The aircraft first flew on September 19, 1962, piloted by Conroy and co-pilot Clay Lacy. When Van Nuys traffic control realized that Conroy intended to take off, they notified police and fire departments to be on alert. However, the huge aircraft performed flawlessly, the only difference in handling being a slight decrease in speed caused by extra drag of the larger fuselage.

Carrying the S-IV Saturn I rocket stage, the Guppy saved three weeks' transit time versus barge, for a cost of $16.00 (equivalent to $131.9 today) per mile (1.6 km).

For more details, click here.

Aerocar International's Aerocar (often called the Taylor Aerocar) was an American roadable aircraft designed and built by Moulton Taylor in Longview, Washington in 1949. Although six examples were made, it never entered large-scale production. It is considered one of the first practical flying cars.

Taylor began designing a roadable aircraft in 1946. During a trip to Delaware, he met inventor Robert E. Fulton, Jr., who had designed an earlier roadable airplane, the Airphibian, with detachable wings. Taylor's prototype, the Aerocar, utilized folding wings that allowed the road vehicle to be converted into flight mode in five minutes by one person. When the rear license plate was flipped up, the operator could connect the propeller shaft and attach a pusher propeller. The same engine drove the front wheels through a three-speed manual transmission. When operated as an aircraft, the road transmission was left in neutral (though backing up during taxiing was possible by the using the reverse gear). On the road, the wings and tail unit were towed behind the vehicle. Taylor also put the propeller on the back of the car so it did not have to be removed when the Aerocar went on the road. Aerocars could drive up to 60 miles per hour and had a top airspeed of 110 miles per hour.

Taylor began designing a roadable aircraft in 1946. During a trip to Delaware, he met inventor Robert E. Fulton, Jr., who had designed an earlier roadable airplane, the Airphibian, with detachable wings. Taylor's prototype, the Aerocar, utilized folding wings that allowed the road vehicle to be converted into flight mode in five minutes by one person. When the rear license plate was flipped up, the operator could connect the propeller shaft and attach a pusher propeller. The same engine drove the front wheels through a three-speed manual transmission. When operated as an aircraft, the road transmission was left in neutral (though backing up during taxiing was possible by the using the reverse gear). On the road, the wings and tail unit were towed behind the vehicle. Taylor also put the propeller on the back of the car so it did not have to be removed when the Aerocar went on the road. Aerocars could drive up to 60 miles per hour and had a top airspeed of 110 miles per hour.

For information on testing and certification, plus details of all production models, click here.

Aerocar in roadable format

It received the official name of Super Transporter early on; however, the name Beluga, a whale it resembles, gained popularity and has since been officially adopted. The Beluga XL, based on the Airbus A330 with similar modifications and dimensions, was developed by Airbus to replace the type in January 2020.

Several major aircraft manufacturers are multinational, and it is not unusual for them to have plants in widely separated locations. Airbus is unique in that although it is today a standalone multinational corporation, it was originally a consortium formed by the major British, French, German, and Spanish aerospace companies. The geographic location of Airbus manufacturing is not only influenced by cost and convenience; it is also a matter of aviation history and national interest. Historically, each of the Airbus partners makes an entire aircraft section, which would then be transported to a central location for final assembly; even after the integration of Airbus into a single firm, the arrangement remained largely the same, with Airbus partners becoming subsidiaries or contractors of the multinational pan-European company. The details vary from one model to another, but the general arrangement is for the wings and landing gear to be made in the UK, the tail and doors in Spain, the fuselage in Germany, and the nose and centre-section in France, with final assembly in either Toulouse, France; Hamburg, Germany; or Seville, Spain.

The A300-600ST Beluga shares many design similarities, although substantially differing in appearance, to the Airbus A300 upon which it was based. The wings, engines, landing gear, and the lower part of the fuselage remain identical to those used on the conventional A300, while the upper part of the fuselage forms an enormous horseshoe-shaped structure 7.7 m (25 ft) in diameter. In comparison with the Super Guppy, the payload was more than doubled and the volume increased by more than 30 per cent. The General Electric CF6-80C2 turbofan engines used are slightly uprated from those used on the standard A300 as well. The vertical stabilizer uses a modified Airbus A340 fin with a 1.12 m (3 ft 8 in) base extension while the tailplane was strengthened and fitted with auxiliary fins to maintain directional stability. The tailplane trim tank was also deleted.

Number built    5

For more details on the development, design and operational history, click here.

built by Airbus to replace the original Airbus Beluga in the movement of oversized aircraft components like wings the aircraft made its first flight on 19 July 2018, and received its type certification on 13 November 2019. The BelugaXL entered service with Airbus Transport on 9 January 2020.

In 2013, the five original BelugaSTs could not cope with production growth, and Airbus evaluated the Antonov An-124 and An-225, Boeing C-17 or Dreamlifter, and A400M, before choosing to modify one of its own aircraft. The programme was launched in November 2014 to build five aircraft to replace the existing five BelugaSTs; the design freeze was announced on 16 September 2015. The program cost is €1 billion for development and production.

The original BelugaSTs were not to be withdrawn from service when the BelugaXL is introduced; a mixed fleet is to operate for at least five years, as the increased production rate of single-aisle aircraft requires the ability to move more parts. The BelugaST fleet flew more than 8000 hours in 2017, doubled from 2014, but the five BelugaST aircraft are only halfway through their planned service life: another operator could use them for civil or military logistic applications.

For more details, click here.

Until the Boeing 747-8F, the An-124 was, for thirty years, the world's heaviest gross weight production cargo airplane and second heaviest operating cargo aircraft, behind the one-off Antonov An-225 Mriya (a greatly enlarged design based on the An-124). The An-124 remains the largest military transport aircraft in current service. The lead designer of the An-124 (and the An-225) was Viktor Tolmachev.

During development it was known as Izdeliye 400 (Product #400) in house, and An-40 in the West. First flown in 1982, civil certification was issued on 30 December 1992. In July 2013, 26 An-124s were in commercial service with 10 on order.

In August 2014, it was reported that plans to resume joint production of the Antonov An-124 had been shelved due to the ongoing political tensions between Russia and Ukraine. The sole remaining production facility is Russia's Aviastar-SP in Ulyanovsk. The various operators of the An-124 are in discussions with respect to the continuing airworthiness certification of the individual An-124 planes. The original designer of the An-124 is responsible for managing the certification process for its own products, but the Russia-Ukraine conflicts are making this process difficult to manage. In 2019, there were 26 An-124s in commercial service.

A total of 55 An-124's were produced. It is listed as a military transport, but it is included in the Unique Aircraft section, because of its size, weight carrying capacity and because 26 are in commercial service.

For details of the development, design and operational history of the An-124, click here.

The Antonov An-225 Mriya (Ukrainian: Антонов Ан-225 Мрія, lit. 'dream' or 'inspiration'; NATO reporting name: Cossack) is a strategic airlift cargo aircraft that was designed by the Antonov Design Bureau in the Ukrainian SSR within the Soviet Union during the 1980s. It is powered by six turbofan engines and is the heaviest aircraft ever built, with a maximum takeoff weight of 640 tonnes (710 short tons; 630 long tons). It also has the largest wingspan of any aircraft in operational service. The single example built has the Ukrainian civil registration UR-82060. A second airframe with a slightly different configuration was partially built. Its construction was halted in 1994 because of lack of funding and interest, but revived briefly in 2009, bringing it to 60–70% completion. On 30 August 2016, Antonov agreed to complete the second airframe for Airspace Industry Corporation of China (not to be confused with the Aviation Industry Corporation of China) as a prelude to commencing series production.

Based on Antonov's earlier An-124, the An-225 has fuselage barrel extensions added fore and aft of the wings. The wings also received root extensions to increase span. The wings are anhedral. The flight control surfaces are controlled via fly-by-wire and triple-redundant hydraulics. Two more Progress D-18T turbofan engines were added to the new wing roots, bringing the total to six. An increased-capacity landing gear system with 32 wheels was designed, some of which are steerable, enabling the aircraft to turn within a 60-metre-wide (200 ft) runway. Like its An-124 predecessor, the An-225 has nose gear designed to "kneel" so cargo can be more easily loaded and unloaded. Unlike the An-124, which has a rear cargo door and ramp, the An-225 design left these off to save weight, and the empennage design was changed from a single vertical stabilizer to a twin tail with an oversized, swept-back horizontal stabilizer. The twin tail was essential to enable the plane to carry large, heavy external loads that would disturb the airflow around a conventional tail. Unlike the An-124, the An-225 was not intended for tactical airlifting and is not designed for short-field operation.

For details of the development, design and operational history, click here.

The Avro Canada VZ-9 Avrocar was a VTOL aircraft developed by Avro Canada as part of a secret U.S. military project carried out in the early years of the Cold War. The Avrocar intended to exploit the Coandă effect to provide lift and thrust from a single "turborotor" blowing exhaust out of the rim of the disk-shaped aircraft. In the air, it would have resembled a flying saucer.

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. In flight testing, the Avrocar proved to have unresolved thrust and stability problems that limited it to a degraded, low-performance flight envelope; subsequently, the project was cancelled in September 1961.

Through the history of the program, the project was referred to by a number of different names. Avro referred to the efforts as Project Y, with individual vehicles known as Spade and Omega. Project Y-2 was later funded by the U.S. Air Force, who referred to it as WS-606A, Project 1794 and Project Silver Bug. When the U.S. Army joined the efforts it took on its final name "Avrocar", and the designation "VZ-9", part of the U.S. Army's VTOL projects in the VZ series.

The Avrocar was the ultimate result of a series of blue skies research projects by designer "Jack" Frost, who had joined Avro Canada in June 1947 after working for several British firms. He had been with de Havilland from 1942 and had worked on the de Havilland Hornet, de Havilland Vampire jet fighter and the de Havilland Swallow aircraft, where he had been the chief designer on the supersonic research project.

At Avro Canada, he had worked on the Avro CF-100 before creating a research team known as the "Special Projects Group" (SPG). Frost first surrounded himself with a collection of like-minded "maverick" engineers, then arranged for a work site. Initially ensconced in the "Penthouse", a derisive nickname for the executive wing of the Administration Building, the SPG was subsequently relocated to a Second World War-era structure across from the company headquarters, the Schaeffer Building, that was secured with security guards, locked doors and special pass cards. At times, the SPG also operated out of the Experimental Hangar where it shared space with other esoteric Avro project teams.

For more details of the design, development and history of the Avrocar, click here.

 The TSR-2 was designed to penetrate a well-defended forward battle area at low altitudes and very high speeds, and then attack high-value targets in the rear with nuclear or conventional weapons. Another intended combat role was to provide high-altitude, high-speed stand-off, side-looking radar and photographic imagery and signals intelligence, aerial reconnaissance. Only one airframe flew and test flights and weight-rise during design indicated that the aircraft would be unabl to meet its original stringent design specifications. The design specifications were reduced as the result of flight testing.

The TSR-2 was to be powered by two Bristol-Siddeley Olympus reheated turbojets, advanced variants of those used in the Avro Vulcan. The Olympus would be further developed and would power the supersonic Concorde.[57] The design featured a small shoulder-mounted delta wing with down-turned tips, an all-moving swept tailplane and a large all-moving fin. Blown flaps were fitted across the entire trailing edge of the wing to achieve the short takeoff and landing requirement, something that later designs would achieve with the technically more complex swing-wing approach. No ailerons were fitted, control in roll instead being implemented by differential movement of the slab tailplanes. The wing loading was high for its time, enabling the aircraft to fly at very high speed and low level with great stability without being constantly upset by thermals and other ground-related weather phenomena.

For more details on the development, design and operational history of the TSR 2, click here.

The Ball-Bartoe JW-1 Jetwing was a US research aircraft flown in the 1970s to investigate blown wing technology.

The Jetwing was a small, mid-wing design powered by a turbofan and fitted with tail-wheel undercarriage. The upper surface of the swept wings incorporated a slot along 70% span, through which air from the engine's fan stage could be discharged. Mounted above this slot was a small secondary airfoil called an "augmentor", intended to direct the discharged airflow over the wing. With this arrangement, it was found that the aircraft remained controllable at airspeeds as low as 34.76 kn (64.38 km/h; 40.00 mph).

The US Navy considered developing the Jetwing for use on short aircraft carriers. A new series of test flights were then carried out. Despite its top speed of 350 mph, the Navy was able to land the Jetwing in a mere 300 feet. Ultimately, the Navy discontinued blown-wing research in favor of vectored thrust technology. Following the test program, the aircraft was donated to the University of Tennessee Space Institute in Tullahoma, which donated the Jetwing to the Wings Over the Rockies Air and Space Museum in Denver, Colorado in 2007. Only one prototype/test machine was built.

The Bartini Beriev VVA-14 Vertikaľno-Vzletayushchaya Amfibiya (vertical take-off amphibious aircraft) was a wing-in-ground-effect aircraft developed in the Soviet Union during the early 1970s. Designed to be able to take off from the water and fly at high speed over long distances, it was to make true flights at high altitude, but also have the capability of flying efficiently just above the sea surface, using aerodynamic ground effect. The VVA-14 was designed by Italian-born designer Robert Bartini in answer to a perceived requirement to destroy United States Navy Polaris missile submarines. The final aircraft was retired in 1987.

Bartini, in collaboration with the Beriev Design Bureau intended to develop the prototype VVA-14 in three phases. The VVA-14M1 was to be an aerodynamics and technology testbed, initially with rigid pontoons on the ends of the central wing section, and later with these replaced by inflatable pontoons. The VVA-14M2 was to be more advanced, with two starting engines to blast into the cavity under the wing to give lift and later with a battery of lift engines to give VTOL capability, and with fly-by-wire flight controls. The VVA-14M3 would see the VTOL vehicle fully equipped with armament and with the Burevestnik computerised anti-submarine warfare (ASW) system, Bor-1 magnetic anomaly detector (MAD) and other operational equipment.

After extensive research, including the development of the small prototype Be-1 wing in ground effect aircraft, the first VVA-14 prototype was completed in 1972. Its first flight was from a conventional runway on 4 September 1972.

In 1974, inflatable pontoons were installed, though their operation caused many problems. Flotation and water taxi tests followed, culminating in the start of flight testing of the amphibious aircraft on 11 June 1975.

The inflatable pontoons were later replaced by rigid pontoons, while the fuselage was lengthened and the starting engines added. This incarnation was given the designation 14M1P. The bureau supplying the intended battery of 12 RD-36-35PR lift engines did not deliver, and this made VTOL testing impossible.

After Bartini's death in 1974, the project slowed and eventually drew to a close, the aircraft having conducted 107 flights, with a total flight time of 103 hours. The only remaining VVA-14, No. 19172, was retired to the Soviet Central Air Force Museum, Moscow in 1987. As a result of uncertain accidents during the shipping to museum, the aircraft received some damage, but these damages were not repaired afterwards. The aircraft still resides at the museum in a dismantled state, where it carries the designations "10687" and "Aeroflot".

At this time many aircraft manufacturers in the United States anticipated a boom in civil aviation and a large number of designs left the drawing board only to ultimately fail. The Model 34 was one of these failures, partly because of its unusual design, and partly because of the thousands of ex-military transport aircraft that were available at the time for a fraction of the price of a new aircraft.

The design was a four-engine high-wing monoplane with tricycle undercarriage, originally designed for 14 (three abreast seating with six additional seats mounted on the side) and eventually converted to take 20 passengers. The side "couch seats" were also able to be folded away so that cargo could be carried internally in the cabin. Individual storage space was provided for each passenger seat on the fuselage side above the seat. In order to accommodate a larger cargo load, a cargo hatch was located near the pilot's compartment.

The unusual aspects of the design were the butterfly or V-tail and engine layout that led to its popular nickname, "Twin Quad." The four engines were buried in the wings, with each pair of engines connected to a single propeller via clutches and a common gear box. The engines were horizontally opposed eight-cylinder air-cooled Lycoming GSO-580s[1] (GSO denoting Geared Supercharged and Opposed, with each engine featuring a built-in reduction gear box in addition to the common propeller gear box). The engines were rated at 400 horsepower at 3,300 rpm. The tail was unusual because unlike the vertical and two horizontal surfaces found on most aircraft, the Twin-Quad's was a two-surface V-tail similar to the tail fitted to Beechcraft's other new product at the time, the Model 35 Bonanza. The V-tail configuration was flight-tested on a twin-engine Beech AT-10.

Another, but more conventional, design aspect was that the belly was made strong enough to sustain minimal damage in the event of a "wheels-up" landing, with built-in integral landing keels or "skids." The wing measured 70 ft (21 m) from tip to tip and the fuselage was 53 ft (16 m) long. With the top of the V-tail almost 18 ft (5.5 m) above the ground and a design maximum takeoff weight (MTOW) of 20,000 lbs, the Model 34 is to date the largest and heaviest Beechcraft civil design, with only the smaller XA-38 Grizzly military aircraft outweighing it.

Number built    1 (two prototypes in production scrapped), hence its categorisation as a Unique Aircraft.

For details of the brief operational history, click here.

The Beecraft Wee Bee was an American ultralight monoplane designed and built by Beecraft. (Not to be confused with Beechcraft) It was described as the world's smallest plane. Later the Starr Bumble Bee II would claim that title.

The Wee Bee was designed by William "Bill" Chana, Kenneth Coward, Karl Montijo and Jim Wilder, who designed the engine. They described it as big enough to carry a man and small enough to be carried by a man.

It was an all-metal cantilever mid-wing monoplane powered by a Kiekhaefer O-45-35 flat-twin piston engine. It had a conventional tail and fixed tricycle landing gear. The unusual feature was that the aircraft lacked any internal room for a pilot who had to fly it lying prone atop the fuselage.

Only a prototype registration NX90840 was built, and the type did not enter production. The prototype was destroyed when the original San Diego Air and Space Museum burned down in 1978. After the fire, a replica was built and is now on display at the new San Diego Air & Space Museum in Balboa Park.

The Wee Bee is pictured below beside the worlds largest piston engined aircraft, the Convair XC-99.

The Bell X-5 was the first aircraft capable of changing the sweep of its wings in flight. It was inspired by the untested wartime P.1101 design of the German Messerschmitt company. In contrast with the German design, which could only have its wing sweepback angle adjusted on the ground, the Bell engineers devised a system of electric motors to adjust the sweep in flight.

The incomplete Messerschmitt P.1101 fighter prototype recovered by United States troops in 1945 from the experimental facility at Oberammergau, Germany, was brought back to the United States. Although damaged in transit, the innovative fighter prototype was delivered to the Bell factory at Buffalo, New York where company engineering staff studied the design closely, and, led by Chief Designer Robert J. Woods, submitted a proposal for a similar design.
 

Although superficially similar, the X-5 was much more complex than the P.1101, with three sweep positions: 20°, 40° and 60°, creating an inflight "variable-geometry" platform. A jackscrew assembly moved the wing's hinge along a set of short horizontal rails, using disc brakes to lock the wing into its inflight positions. Moving from full extension to full sweep took less than 30 seconds. The articulation of the hinge and pivots partly compensated for the shifts in center of gravity and center of pressure as the wings moved.

Even so, the X-5 had vicious spin characteristics arising from the aircraft's flawed aerodynamic layout, particularly a poorly positioned tail and vertical stabilizer which, in some wing positions, could lead to an irrecoverable spin. This violent stall / spin instability would eventually cause the destruction of the second aircraft and the death of its Air Force test pilot in 1953.

The unfavorable spin characteristics also led to the cancellation of tentative plans by the United States Air Force to modify the X-5's design into a low-cost tactical fighter for NATO and other foreign countries.

Two X-5s were built (serial numbers 50-1838 and 50-1839). The first was completed 15 February 1951, and the two aircraft made their first flights on 20 June and 10 December 1951. Almost 200 flights were made at speeds up to Mach 0.9 and altitudes of 40,000 ft (12,000 m). One aircraft was lost on 14 October 1953, when it failed to recover from a spin at 60° sweepback. Air Force Captain Ray Popson died in the crash at Edwards Air Force Base. The other X-5 remained at Edwards and continued active testing until 1955, and remained in service as a chase plane until 1958.

The X-5 successfully demonstrated the advantage of a swing-wing design for aircraft intended to fly at a wide range of speeds. Despite the X-5's stability problems, the concept was developed to an outboard rather than inboard hinge, and was later successfully implemented in such aircraft as the General Dynamics F-111 and Grumman F-14 Tomcat, the Mikoyan Gurevich MiG-23 and MiG-27, the Sukhoi Su-17/20/22 and Su-24, the Tupolev Tu-22M and Tu-160, the Panavia Tornado and the Rockwell B-1 Lancer.

The Bell YFM-1 Airacuda was an American heavy fighter aircraft, developed by the Bell Aircraft Corporation during the mid-1930s. It was the first military aircraft produced by Bell. Originally designated the Bell Model 1, the Airacuda first flew on 1 September 1937. The Airacuda was marked by bold design advances and considerable flaws that eventually grounded the aircraft.

The Airacuda was Bell Aircraft's answer for a "bomber destroyer" aircraft. Although it did see limited production, and one fully operational squadron was eventually formed, only one prototype and 12 production models were ultimately built, in three slightly different versions.

In an effort to break into the aviation business, Bell Aircraft created a unique fighter concept touted to be "a mobile anti-aircraft platform" as well as a "convoy fighter." Created to intercept enemy bombers at distances beyond the range of single-seat fighter interceptors, the YFM-1 (Y, service test; F, fighter; M, multiplace) was an innovative design incorporating many features never before seen in a military aircraft, as well as several never seen again. Using a streamlined, "futuristic" design, the Bell Airacuda appeared to be "unlike any other fighters up to that time."

According to Major Alexander De Seversky's 1942 book, Victory Through Air Power, the Bell Airacuda "represents a great engineering achievement. But its designation as ′convoy fighter′ is erroneous, since that requires different disposition of armament. With its maximum firepower directed forward, it really offers a preview of an effective long-range interceptor fighter."

A forward-firing 37 mm (1.46 in) M4 cannon with an accompanying gunner was mounted in a forward compartment of each of the two engine nacelles. Although capable of aiming the cannons, the gunners' primary purpose was simply to load them with the 110 rounds of ammunition stored in each nacelle.

The crew of five included the pilot and gunners; a copilot/navigator who doubled as a fire-control officer, using a Sperry Instruments "Thermionic" fire control system (originally developed for anti-aircraft cannon) combined with a gyro-stabilised and an optical sight to aim the weapons; and a radio operator/gunner armed with a pair of machine guns stationed at mid-fuselage waist blisters for defense against attack from the rear.

An unusual feature of the Airacuda was the main door for entry. The door was opened and pulled down and hinges folded in on three steps for the crew to climb into the aircraft.

For more information on design flaws, accidents and variants, click here.

The DB-LK (Dahl'niy Bombardirovshchik-LK – long-range bomber–flying wing) was a bomber aircraft designed and built in the USSR in 1939.

Viktor Nikolayevich Belyayev had an illustrious early career with TsAGI, AVIAVnito, Aeroflot, OMOS, AGOS, KOSOS and the Tupolev OKB. He also designed and built several gliders from 1920, including flying wing designs, and in 1934 he designed a transport aircraft with twin tail-booms each accommodating ten passengers.

Belyaev developed the twin boom idea into the twin-fuselage DB-LK, which had two short fuselages either side of a very long chord wing centre section, with the outer wing sections swept forward 5 deg 42 min, tapering at 7:1 out to raked back tips. A large fin and rudder on a short central boom, carried a small tailplane with very large elevators.

The airframe was of light alloy stressed skin construction with five spar wings covered with sheet aluminium alloy. Each fuselage pod carried a single M-88 engine in a long chord cowling, driving a three-bladed VISh-23D propeller, as well as a pilot/navigator cockpit and radio operator/gunner station in each of the extensively glazed tail-cones. The outer wings had slats, ailerons and 45deg Zap flaps, the raked tips also had small ailerons. The retractable undercarriage consisted of single main legs in the fuselage pods aft of the engines and a tail-wheel in the base of the fin.

Before flight trials began, the test pilot, M.A. Nyukhtikov, carried out many fast taxis to assess the handling of the unconventional DB-LK, one of which ended in an undercarriage collapse. Flight trials eventually got under way early in 1940 revealing an excellent performance, but with a high sensitivity to centre of gravity changes. Production was not authorised.

The Blohm & Voss BV 141 was a World War II German tactical reconnaissance aircraft, notable for its uncommon structural asymmetry. Although the Blohm & Voss BV 141 performed well, it was never ordered into full-scale production, for reasons that included the unavailability of the preferred engine and competition from another tactical reconnaissance aircraft, the Focke-Wulf Fw 189.

In 1937, the German Air Ministry – the Reichsluftfahrtministerium (RLM) – issued a specification for a single-engine reconnaissance aircraft with optimal visual characteristics. The preferred contractor was Arado with the Ar 198, but the prototype proved unsuccessful. The eventual winner was the Focke-Wulf Fw 189 Uhu; even though its twin-boom design using two smaller engines did not match the requirement of a single engined aircraft. Blohm & Voss (Hamburger Flugzeugbau) although not invited to participate, pursued as a private venture something far more radical. The proposal of chief designer Dr. Richard Vogt was the uniquely asymmetric BV 141.

The Plexiglas-glazed crew gondola on the starboard side strongly resembled that found on the Fw 189, and housed the pilot, observer and rear gunner, while the fuselage on the port side led smoothly from the BMW 132N radial engine to a tail unit.

At first glance, the placement of weight would have induced tendency to roll, but the weight was evenly supported by lift from the wings.

In terms of thrust vs drag asymmetry, the countering of induced yaw was a more complicated matter. At low airspeed, it was calculated to be mostly alleviated because of a phenomenon known as P-factor, while at normal airspeed it proved to be easily controlled with trimming.

The tailplane was symmetrical at first, but in the 141B it became asymmetrical – starboard tailplane virtually removed – to improve the rear gunner's fields of view and fire.

Three prototypes and an evaluation batch of five BV 141As were produced, backed personally by Ernst Udet, but the RLM decided on 4 April 1940 that they were underpowered, although it was also noted they otherwise exceeded the requirements. By the time a batch of 12 BV 141Bs were built with the more powerful BMW 801 engines, they were too late to make an impression, as the RLM had already decided to put the Fw 189 into production. An urgent need for BMW 801 engines for use in the Fw 190 fighter aircraft reduced the chance of the BV 141B being produced in quantity.

For more details and variants, click here.

The Blohm & Voss BV 40 was a German glider fighter designed to attack Allied bomber formations during the time of the bombing raids over Nazi Germany.

The BV 40 was the smallest glider that could accommodate an armoured cockpit and two cannon with limited ammunition. By eliminating the engine and lying the pilot in a prone position (i.e. on his front), the cross-sectional area of the fuselage was much reduced, making the BV 40 harder for bomber gunners to hit.

The plane was designed to use non-strategic materials and to be built in as short a time as possible by non-skilled workers. The fuselage was constructed almost entirely of wood. It was of conventional layout, the glider had a high-mounted, straight untapered wing with a similarly-shaped tailplane mounted on the fin just above the fuselage. The pilot lay prone in an armoured steel cockpit in the nose of the aircraft. The front steel plate was 20 millimetres (0.79 in) thick, and was fitted with a windscreen of 120-millimetre (4.7 in) thick, armoured glass[3] that gave the aircraft a blunt-nosed appearance.

Two 30 mm (1.18 in) MK 108 cannon were mounted in the wing roots.

There was no conventional undercarriage. A twin-wheeled dolly was used for take-off and dropped once the glider was airborne. A skid under the nose was lowered for landing.

The BV 40 interceptor glider was conceived by Dr Richard Vogt, chief designer and technical director of Blohm & Voss, as a low-cost emergency solution to the problem of the Allied bomber formations which were devastating Germany in the latter half of World War II. It was to be towed by a Messerschmitt Bf 109 to operational altitude and released above the Allied bombers' combat box. Once released, it would dive down at a sharp angle towards the enemy bomber fleet. During its short attack time, the BV 40 would fire its weapons, then glide back to earth. Several prototypes were completed and flown, towed behind a Messerschmitt Bf 110. The first flight took place in May 1944. It was found the craft could reach 292 miles per hour (470 km/h) and it was thought to have the potential to go far faster. Various changes to the requirement and to the design were discussed, before the project was cancelled later in the year. In all, seven aircraft were completed and five of them flown. Owing to the potential dangers for the pilot inherent in the operation of this precarious aircraft, the BV 40 is sometimes listed as a suicide weapon, but it was not intended as such.

It also known as the Boeing 747-400 Large Carg o Freighter (LCF). With a volume of 65,000 cubic feet (1,840 m³) the Dreamlifter can hold three times that of a 747-400F freighter. It is used primarily for transporting Boeing 787 Dreamliner aircraft components to Boeing's assembly plants from suppliers around the world.

Boeing Commercial Airplanes announced on October 13, 2003 that, due to the length of time required by land and marine shipping, air transport will be the primary method of transporting parts for the assembly of the Boeing 787 Dreamliner (then known as the 7E7). Boeing 787 parts were deemed too large for standard marine shipping containers as well as the Boeing 747-400F, Antonov An-124 and Antonov An-225. Initially, three used passenger 747-400 aircraft were to be converted into an outsize configuration in order to ferry sub-assemblies from Japan and Italy to North Charleston, South Carolina, and then to Washington state for final assembly, but a fourth was subsequently added to the program. The Large Cargo Freighter has a bulging fuselage similar in concept to the Super Guppy and Airbus A300-600ST Beluga outsize cargo aircraft, which are also used for transporting wings and fuselage sections.

Of the four 747 Dreamlifters Boeing acquired, three were complete and operational by June 2008, and the fourth became operational in February 2010.

On July 1, 2020, a Dreamlifter arrived at Salt Lake City International Airport, carrying 500,000 face masks to be used by Utah school children and teachers as part of the state's response to the Coronavirus disease 2019 pandemic. The flight was a joint effort between Boeing, Atlas Air, H.M. Cole, Cotopaxi, Flexport, UPS and the state of Utah.

For more information, click here.

Its length, slender cross-section and intended purpose led to its being nicknamed the "Flaming Pencil".

The aircraft had its genesis in Operational Requirement 330 for a high speed (Mach 3) reconnaissance aircraft, which eventually developed into the Avro 730. As the 730 was expected to operate at high speeds for extended periods of time, more data was needed on high speed operations, leading to Operational Requirement ER.134T for a testbed capable of speeds greater than Mach 2. The aircraft was expected to run at these speeds for extended periods of time, allowing it to study kinetic heating effects on such an aircraft. The aircraft was expected to spend a considerable amount of time with a skin temperature around 300 Celsius.

Several firms took interest in this very advanced specification and the eventual contract (6/Acft/10144) was awarded to Bristol Aircraft in February 1953.

Bristol gave the project the type number 188, of which three aircraft were to be built, one a pure test bed and the other two (constructor numbers 13518 and 13519) for flight testing. Under contract number KC/2M/04/CB.42(b) serial numbers XF923 and XF926 were given on 4 January 1954 to the two that would fly. To support the development of the Avro 730 Mach 3 reconnaissance bomber, another three aircraft were ordered (Serial Numbers XK429, XK434 and XK436). The follow-up order was cancelled when the Avro 730 programme was cancelled in 1957 as part of that year's review of defence spending. The 188 project was continued as a high speed research aircraft.

For more details of development and design, and operational history, click here.

The Caproni Ca.60 Transaereo, often referred to as the Noviplano (nine-wing) or Capronissimo, was the prototype of a large nine-wing flying boat intended to become a 100-passenger transatlantic airliner. It featured eight engines and three sets of triple wings.

Only one example of this aircraft, designed by Italian aviation pioneer Gianni Caproni, was built by the Caproni company. It was tested on Lake Maggiore in 1921: its brief maiden flight took place on February 12 or March 2. Its second flight was March 4; shortly after takeoff, the aircraft crashed on the water surface and broke up upon impact. The Ca.60 was further damaged when the wreck was towed to shore and, in spite of Caproni's intention to rebuild the aircraft, the project was soon abandoned because of its excessive cost. The few surviving parts are on display at the Gianni Caproni Museum of Aeronautics and at the Volandia aviation museum in Italy.

As early as 1913 Caproni, then aged 27, had said during an interview for the Italian sports newspaper La Gazzetta dello Sport that "aircraft with a capacity of one hundred and more passengers" would soon become a reality. It was after the war, however, that (besides converting some of his large wartime bombers into airliners) Caproni began designing a huge and ambitious passenger flying boat; he first took out a patent on a design of this kind on February 6, 1919.

The idea of a large multi-engined flying boat designed for carrying passengers on long-range flights was considered, at the time, rather eccentric. Caproni thought, however, that such an aircraft could allow the travel to remote areas more quickly than ground or water transport, and that investing in innovative aerial means would be a less expensive strategy than improving traditional thoroughfares. He affirmed that his large flying boat could be used on any route, within a nation or internationally, and he considered operating it in countries with large territories and poor transport infrastructures, such as China.

Caproni believed that, to attain these objectives, rearranging wartime aircraft would not be sufficient. On the contrary, he thought that a new generation of airliners (featuring extended range and increased payload capacity, the latter in turn allowing a reduction in cost per passenger) had to supersede the converted leftovers from the war. 

In spite of criticism from some important figures in Italian aviation, especially aerial warfare theorist Giulio Douhet, Caproni started designing a very innovative aircraft and soon, in 1919, he took out a patent on it.

For more details of development, design, testing, etc., click here.

The Caproni Ca.90 was a prototype Italian heavy bomber designed and built by Caproni. When it first flew in 1929 it was the largest land-based aircraft in the world.

A six-engined inverted sesquiplane, the Caproni Ca.90 was designed as a heavy bomber and first flew in 1929. It had two tandem pairs of 1,000 hp (746 kW) Isotta Fraschini Asso 1000 W-18 inline piston engines mounted above the lower wing, each pair driving a four-bladed pusher and a two-bladed tractor propeller. Another pair of engines was mounted above the fuselage. Only one Ca.90 was built.

Although the Dornier Do X flying boat that flew later in 1929 had a larger wingspan and weight, the Caproni Ca.90 remained the largest landplane until the arrival of the Tupolev ANT-20 in 1934, but remains the largest biplane.

The Convair Model 118 ConvAirCar (also known as the Hall Flying Automobile) was a prototype flying car of which two were built. Intended for mainstream consumers, two prototypes were built and flown. The first prototype was lost in an accident due to fuel exhaustion. Subsequently, the second prototype was rebuilt from the damaged aircraft and flown. By that time, little enthusiasm remained for the project and the program ended shortly thereafter.

Consolidated Vultee Aircraft (later Convair) was seeking entry into the post-war aviation boom with a mainstream flying car. Theodore P. "Ted" Hall had studied the concept of a flying car before World War II, with Consolidated unsuccessfully proposing the idea for use in commando-type raids. Following the end of the war, Hall and Tommy Thompson designed and developed the Convair Model 116 Flying Car, featured in Popular Mechanics magazine in 1946, which consisted of a two-seat car body, powered by a rear-mounted 26 hp (19 kW) engine, with detachable monoplane wings and tail, fitted with their own tractor configuration 90 hp (67 kW) Franklin 4A4 engine driving a two-bladed wooden propeller. This flew on July 12, 1946, completing 66 test flights.

Hall subsequently designed a more sophisticated development of the Model 116, with a more refined car body and a more powerful "flight" engine. A 25 hp (19 kW) Crosley engine was in the rear, powering the plastic-bodied four-seat car and a 190 hp (142 kW) Lycoming O-435C was used for the powerplant of the aircraft. A lofty production target of 160,000 was planned, with a projected $1,500 price tag. Convair anticipated that the Model 118 would be purchased in large numbers to be rented at airports.

Test pilot Reuben Snodgrass flew the prototype, registration No. NX90850, for the first time on November 15, 1947. On November 18, 1947, while on a one-hour demonstration flight, it made a low fuel forced landing near San Diego, California, destroying the car body and damaging the wing. The pilot, who escaped with minor injuries, reportedly took off with little or no aviation fuel aboard. Although the fuel gauge he had visually checked during the pre-flight check indicated that the tank was full, it was the automobile's fuel gauge, not the aircraft's gauge. Using the same wing and another car body, the second prototype flew again on January 29, 1948, piloted by W.G. Griswold, but enthusiasm for the project waned and Convair cancelled the program. The rights reverted to Hall, who formed T.R Hall Engineering Corp., but the Model 118 in its new incarnation never achieved production status.

Prototype 2

The Convair XC-99, AF Ser. No. 43-52436, is a prototype heavy cargo aircraft built by Convair for the United States Air Force. It was the largest piston-engined land-based transport aircraft ever built, and was developed from the Convair B-36 Peacemaker bomber, sharing the wings and some other structures with it. The first flight was on 24 November 1947 in San Diego, California, and after testing it was delivered to the Air Force on 26 May 1949. The Convair Model 37 was a planned civil passenger variant based on the XC-99 but was not built.

Design capacity of the XC-99 was 100,000 lb (45,000 kg) of cargo or 400 fully equipped soldiers on its double cargo decks. A cargo lift was installed for easier loading. The engines face rearward in a pusher configuration.

The Convair Model 37 was a large civil passenger design derived from the XC-99 but was never built. The Model 37 was to be of similar proportions to the XC-99; 182 ft 6 in (55.63 m) length, 230 ft (70 m) wingspan, and a high-capacity, double-deck fuselage. The projected passenger load was to be 204, and the effective range of 4,200 mi (6,800 km).

Fifteen aircraft were ordered by Pan American Airways for transatlantic service. However, the fuel and oil consumption of the six 3,500 hp (2,600 kW) Wasp Major radials powering the XC-99 and B-36 meant that the design was not economically viable, and the hoped-for turboprop powerplants did not materialize fast enough. The low number of orders were not sufficient to initiate production, and the project was abandoned.

In July 1950, the XC-99 flew its first cargo mission, "Operation Elephant." It transported 101,266 pounds (45,933 kg) of cargo, including engines and propellers for the B-36, from San Diego to Kelly Air Force Base in San Antonio, Texas, a record it would later break when it lifted 104,000 lb (47,200 kg) from an airfield at 5,000 ft (1,500 m) elevation. In August 1953, the XC-99 would make its longest flight, 12,000 mi (19,000 km), to Rhein-Main Air Base, Germany, by way of Kindley Air Force Base, Bermuda and Lajes Field in the Azores. It carried more than 60,000 lb (27,000 kg) each way. It attracted much attention everywhere it flew.

The US Air Force determined that it had no need for such a large, long-range transport at that time, and no more were ordered. The sole XC-99 served until 1957, including much use during the Korean War. It made twice weekly trips from Kelly AFB to the aircraft depot at McClellan Air Force Base, California, transporting supplies and parts for the B-36 bomber while returning by way of other bases or depots making pick-ups and deliveries along the way. During its operational life, the XC-99 logged over 7,400 hours total time, and transported more than 60 million pounds (27,000 metric tons) of cargo. The aircraft made its last flight on 19 March 1957, landing at Kelly Air Force Base, where it would remain for the next 47 years. The then-United States Air Force Museum at Wright-Patterson Air Force Base near Dayton, Ohio, requested that the aircraft be flown there for display, but the Air Force refused due to the $7,400 cost of the flight.

The Pogo had delta wings and three-bladed contra-rotating propellers powered by a turboprop engine. It was intended to be a high-performance fighter aircraft capable of operating from small warships. Landing the XFY-1 was difficult, as the pilot had to look over his shoulder while carefully working the throttle to land.

After World War II, the Cold War prompted the United States Army and Navy to study VTOL operations. It was envisaged to protect task forces, convoys or any fleet, even without aircraft carriers, by placing VTOLs on any ship. These fighters would be housed within a conical protective housing, saving limited deck space available aboard ships. They would provide first line of airborne defense and reconnaissance capability, before more aircraft could be scrambled to help.

The XFY-1 was designed for the Allison XT40-A-14 turboprop, which was expected to deliver 7,100 shp (5,295 kW). The production aircraft were intended to use the even more powerful Allison T54 which was never built. It was one of the few propeller-driven aircraft with delta wings, swept at 52 degrees, and a fin with a span of 21 ft 8 in (6.5 m). The pilot's seat was mounted on gimbals allowing for movement from 45 degrees in vertical flight to 90 degrees in horizontal flight. The Curtiss-Wright turbo-electric three-bladed contra-rotating propellers were 16 feet (4.88 m) in diameter. Only one xample was produced.

For details of the operational history of the XFY, click here.