Why are some planes transparent?


Last night I downloaded a DC-3 and it appeared on my screen just fine, however, there were some other problems so I deleted it. Today I found out some workarounds to the problems so I downloaded it again. However, this time the plane is almost totally invisible. Sort of like Wonder Woman's plane.

Any ideas what is doing on or how to fix it? I deleted the plane I downloaded yesterday so that I could start from scratch.