Like tailfins on cars, delta wing was all the rage on aircraft in the 1950’s ....
Avro Arrow, F-102, F-106, Concord, Vulcan, Mirage, Typhoon, MiG-21, XB-70 to name a few.
Then in the 1960’s swing-wing was the new hotness.
Remember swing-wing? F-111? F-14? Tornado? MiG-23? No one else does, either.
https://nationalinterest.org/blog/the-b ... ever-21791
[quote]On the whole, the expert test pilots were fond of the light, nimble and simple MiG-21.
But not its successor. “The MiG-23 was a nightmare, maintenance was a nightmare. The guys hated flying it,â€
Though offering the ability to configure an aircraft aerodynamics to meet various flight situations, such as takeoff and landing or low speed versus supersonic speed, the weight and complexity of variable-geometry wings soon made them a Cold War relic.[/quote]