I didn't really comprehend what he did to defeat Mugino.
Can someone explain that?
Yeah, it is kinda confusing.
They stumbled into an air resistance testing room where prototype aircrafts are flight-simulated with very strong winds.
Hamazura used his gun to break the control room's glass which activated the wind blowers. The winds blew Mugino away. While he took cover in the stationary aircraft's cockpit until they turned off.
Logically, this should work the other way around. Since if the glasses break, some security measures should have activated which prevented the blowers from turning on. Also, dealing with winds that strong, the glasses should have been strong enough to withstand gunshots to begin with.