According to FAS, the EL/M was the most advanced airborne early warning and control system. Had it not been for the clown-style nose of the EL/M, it would just appear to be a regular 707 Boeing. The chief objective of the plane was to serve as an intelligence provider to maintain air control and conduct surveillance.
The EL/M-2075 is a solid-state conformal array radar system for use on a 707 Boeing. While it was super-advanced, design-wise, people had an issue with the strange-looking nose making the Phalcon looking very strange. You can’t win it all.
Sikorsky CH-37C Mojave
Introducing this bug-eyed monstrosity; The Ch-37C was a huge, heavy-lift helicopter, which experienced its first-ever flight in 1956, it was also one of the last helicopters to use a piston engine, which was even bigger, heavier, and sadly less powerful than the turboshaft engines. It wasn't all bad though, as the helicopter did help to recover spy satellite film capsules that dropped from space via parachute.
It did provide some decent services but it was terribly strange-looking, which, as it might come as a surprise, is of somewhat importance, even for NASA.
It should be no surprise that this flying machine also got the nickname, "the flying banana," this multi-purpose helicopter used wheels, floats, and skis and even had a winterization feature that allowed it to function at ridiculously low temperatures ( -65 Fahrenheit.)
Piasecki produced the H21 as an Arctic rescue helicopter, which makes sense considering its fantastic cold-proof functionality. But even with all those capabilities as well as the fact that it was equipped for 12 infantrymen or 12 stretchers, and two medical attendants, the helicopter only was in operation between 1952 until 1959. Did it have to do with the ridiculous shape? It's possible.
Engineer Alexander Lippisch was in charge of the Dornier Aerodyne, a wingless VTOL bot-controlled winged aircraft. The thought that Lippisch had conceptualized was for the plane was to merge lift and thrust production into a single unit and flow channel. Lippisch designed it to be a land or ship supported drone for aerial reconnaissance.
Measurements wise, the Aerodyne was 18 feet long and 6 feet wide. Lippisch ended up being part of the Dornier team that produced only one prototype. For some mystery reason, the first flight was in September 1972 and never again as it retired two months later.
North American F-82 Twin Mustang
Two heads are generally better than one, as they usually say. With this theory in mind, one would think it could be applied to plane design. And thus the North American F-82 Twin Mustang was born.
Unfortunately, things did not go according to plan and the "double P-51" that was designed as a long-range escort fighter for WWII, was called off before it was even operational.