Dash 8-300
Flight Crew Air Transport Pilot (ATP)
Human-Machine Interface; Confusion
Inflight Event / Encounter Loss Of Aircraft Control; Inflight Event / Encounter Weather / Turbulence
Flight Crew Regained Aircraft Control; Flight Crew Executed Go Around / Missed Approach
Weather; Procedure; Human Factors
While on approach the plane was stabilized before the 1;000 FT call. The 500 FT call went normally. Shortly after the 500 FT call (Roughly 300-400 FT above the ground) the aircraft started an uncommanded roll followed by an uncommanded yaw both were quiet large. At this point I initiated a go around. After the go around we entered the traffic pattern to make a successful landing on the same runway. The ride on the first attempt to land was smooth until the uncommanded movements. The second attempt to land had light to moderate chop until touch down. I believe the uncommanded movement of the aircraft was the result of windshear. One thing to note after starting the go-around the Tower Controller made numerous unnecessary communications with us. I believe he could have waited until we contacted him since there was no other traffic in the area that needed safety information related to our go around.The ATIS was broadcasting that there were gusty winds; but with the wind check issued with the landing clearance made no mention of gusty winds; plus the controller argued with us about the existence of wind shear. I don't think we could have prevented the go around but we would have been more prepared for it had the Tower issued wind advisories including the gusty winds that were happening prior to our first attempt. I also noticed upon our taxi in to the gate that numerous wind indicators (Trees; flags; windsocks; etc) were all indicating significantly different from each other.
DHC8 crew experienced windshear at low altitude during approach and goes around. The Tower Controller did not provide wind information on check in but did ask unnecessary questions during the go around. The ATIS did indicate that gusty winds were present.