Those are special variants inaccessible to the public, unless HTC decides to enable them. You can only access the regular RV-8 which is found by typing the following text into the radio text box from the tower:
.showrv
or..
.show rv
Afterward head to the hangar, look for it. If it's not there, head back to the tower, then back to the hangar. If it's still not there. Try typing the .DOT Command again.
