There is a pattern to many of the UFO crashes—both location and time.
Many were in the 1940s-1950s period and were in the general area near military bases where advanced radar and microwave technology was under development.
It may have (probably accidentally) disrupted their propulsion system in some way.
Just because it is alien does not make it immune to the laws of physics.
The best source on UFO crashes—dozens of military witnesses explaining the details of their crash retrieval activities is this one:
https://www.amazon.com/UFO-Crash-Retrievals-Investigation-1978-1994/dp/0359685080
There is an actual government manual on this stuff btw—date is 1954:
https://cdn.preterhuman.net/texts/wars_and_weapons/Majestic_12-UFO_Official_Manual.pdf
“It may have (probably accidentally) disrupted their propulsion system in some way.
Just because it is alien does not make it immune to the laws of physics.”
LOL!
Imagine that cave dwellers could disable a modern tank?
“Many were in the 1940s-1950s period and were in the general area near military bases where advanced radar and microwave technology was under development.”
My theory is the UFO crash was the cover story. Remember we snuck von Braun and the other Nazi rocket scientists in through Mexico. We were testing V-2 rockets at White Sands. Maybe it was a V-2 that crashed. Imagine the outrage at that time if it was learned we let those Nazis into the country like that. People were still cheesed off at the Germans then. Our Germans only became the good guys because of the Cold War.