Pretty sure Cobra’s weren’t some of the first helicopters in Vietnam….
Here’s the Huey a friend flew in Vietnam, he was reunited with it last September.

Resto pics:
https://www.facebook.com/media/set/?set=oa.720509271303769&type=3
Some of his Vietnam pics:
https://www.facebook.com/larry.kwiatkowski/media_set?set=a.2174734331969.2106824.1355148869&type=3