© Getty Images

MiG-23 - The Soviet MiG-23 was built as a replacement for the MiG-21, but it never achieved the success of its predecessor. After the Cold War ended, many air forces ditched the MiG-23.

© iStock

Antonov A-40 - How about a flying tank? The A-40 was designed with an attachable glider and towed by a Russian bomber. But it didn't even pass its first test flight.

© Public Domain

Messerschmitt Me 163 Komet - The Komet was a rocket fighter used by the Germans to shoot down Allied bombers. But pilots only had three minutes' worth of fuel with these planes.

© Shutterstock

Beechcraft Starship - Despite its innovative design, the Starship was a failure. Only a handful were sold out of 53 aircraft built.

© Shutterstock

Convair R3Y Tradewind - This was the US Navy's first turboprop flying boat. But engine problems brought production to an end.

© Public Domain

de Havilland DH 106 Comet - The Comet was the world’s first commercial jet-powered airliner.

© Getty Images

de Havilland DH 106 Comet - But safety was an issue. There were 114 aircraft built, and 13 of them were involved in fatal accidents.

© iStock

Airbus A380 - Airbus has announced that they will stop producing their superjumbo jet. This is because Emirates and other airlines, including Qantas, canceled their orders.

© iStock

Airbus A380 - Airbus believed that airlines would need a massive plane such as the A380 to carry over 800 passengers between major airport hubs. But the world's largest airliner failed to become the answer to commercial aviation.

© iStock

Tupolev TU- 144 - Unlike its brother, the Concorde, this Russian supersonic airliner failed to become a success.

© iStock

Tupolev TU- 144 - The first passenger prototype didn't have a great start, crashing at the 1973 Paris Air Show due to a number of system faults. The aircraft flew 55 times in total.

© iStock

Douglas DC-10 - The DC-10 had a major design flaw. Its cargo doors opened outward rather than inward. This caused a number of accidents.

© Getty Images

Douglas TBD DC-10 - This aircraft could only shoot a torpedo flying in a straight line at 115 mph (185 km/h), making it an easy target for enemies.

© Public Domain

A-12 Avenger II - Also known as the "Flying Dorito," this bomber was part of a US Navy program. A number of problems and a cost of US$165 million per aircraft brought the project to an end.

© Public Domain

Aerocar - The dream of finally having a flying car came true in 1949. Six models were made, but none ever entered production.

© Public Domain

PZL M-15 Belphegor - This is one of the world's only jet biplanes, which was used as a crop-sprayer. In total, 175 were built.

© Public Domain

McDonnell XF-85 Goblin - This parasite fighter was unable to dock with the aircraft from which it was launched, and it was also poorly armed.

© Public Domain

Boeing XB-15 - This heavy bomber was the largest plane ever built in the US at the time. But the engine was not powerful enough, so the only aircraft to fly was used as a cargo plane in the Caribbean during WWII.

© Public Domain

Goodyear Inflatoplane - The US Army realized that an inflatable aircraft was not the best option, as just one bullet could bring it down.

© Public Domain

Blackburn Botha -

This bomber was a huge failure. It had poor visibility, and couldn't handle extra weight due to its underpowered engine.

© Getty Images

LWS-6 Żubr - This Polish bomber was incapable of flying with the landing gear retracted. Plus, it couldn't handle any weight, stressing the airframe in such a way that it could simply disintegrate.

© Public Domain

Caproni Ca.60 Transaereo - Despite its nine wings and eight engines, the Caproni crashed in Italy after reaching a height of only 60 ft (18 m).

© Public Domain

Brewster F2A Buffalo - The Buffalo was an extremely heavy aircraft. Japanese fighters would make these drop like birds during WWII.

© Public Domain

Heinkel He-162 - This German fighter had its engine located right above the cockpit. Pilots wanting to escape the aircraft could easily be sucked into it.

© Public Domain

Royal Aircraft Factory B.E.2 - The gunner in this aircraft actually blocked the pilot's view. Its slow speed made it a poor jet fighter during WWI, so it was mostly used to attack German Zeppelins.

© Getty Images

Bonney Gull - Replicating the wings of birds is probably not the answer in aviation. The Bonney Gull crashed in 1928, shortly after takeoff.

© Public Domain

Hiller VZ-1 Pawnee - This hovercraft was another failed project by the US Defense Department. It's now a museum piece.

© Public Domain

Christmas Bullet -

The Christmas Bullet's design is considered by many to be the worst in the history of aviation. It featured unsupported wings intended to flap like a bird's wings.

See also: Take flight for a brief history of aviation

© Public Domain