My self and many others think that rotary and fixed wing models should not share the same air space. It is a catastrophe waiting to happen. Many clubs have a separate area for each. Just like you, when a large rc helicopter takes to the air in near proximity to me, I look for cover. It's those razor sharp blades spinning at incredible rpms I suppose. "If the wings are moving faster that the fuselage it must be a helicopter and therefore unsafe."