He could not hear the officer and only heard the knocks, this is substantiated by the witness as well. When the airman got no response after calling out, as the officer obsecured himself after knocking the first time and was walking around the unit to attempt to look inside, that’s when the airman got the door.

This is not the expected outcome of answering your own door with a legally owned gun in hand, otherwise the 2nd amendment is null and void.