The fact that aliens are able to travel distances of hundreds of light-years to visit planets in other solar systems or galaxies is an emphatic proof of the supremacy of their technologies. It is, hence, always been an endeavor of humans to do reverse engineering of the alien technology to get an understanding of the same and use that technology in the betterment of mankind.
While many things had been known to mankind before, the jump in technology during the 1950s and 60s surely tells us that there was some guidance that led man to come up with technological advancements like never before. Alien theorists believe that this jump in technology is basically a product of conducting reverser engineering on the alleged crashed alien spaceships which are rumored to have been captured in 1947 in Roswell, New Mexico and many other places in the next few years. Here are some evidences that reverse engineering of alien technology is indeed a reality.
(1) The metal Titanium was discovered in 1791, but it was only after 1950 that it started being used for military aviation processes for the making of fighter jets that fly at incredible speeds.
(2) The commercial and military application of fiber optic was not understood till 1958, albeit the fact that it was first demonstrated by Swiss scientists Daniel Colladon and Jacques Babinet more than a hundred years before, in 1840s.
(3) It was in 1947 when the Americans came up with the designs of a transistor, a key element for the making of multiple electronic devices. While attempts to make something like this were on for years, it was not before November 1947 that the scientists could come up with something like a transistor. You may want to be reminded that Roswell crash had happened on 8th July, 1947.
(4) While bullet proof vests were in use even in the World War II, the quality of the vests shot up suddenly during the Korean War that happened in 1950.