Commercial Fixed Wing
Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument; Flight Crew Multiengine
Communication Breakdown; Confusion; Workload
Deviation - Altitude Overshoot; Deviation - Speed All Types; Deviation / Discrepancy - Procedural Clearance; Inflight Event / Encounter Weather / Turbulence; Inflight Event / Encounter Unstabilized Approach
Air Traffic Control Issued New Clearance; Flight Crew Returned To Clearance; Flight Crew Executed Go Around / Missed Approach; Flight Crew Took Evasive Action
Procedure; Weather; Airspace Structure
We were on approach for LAS. We briefed to land on Runway 26L but when we were transferred to approach initially we were not informed that they were planning to bring us to Runway 01L. We only figured it out when we were vectored to right of KEPEC6 approach. Then we inquired which runway were they bringing us. That's the only time we got information about the runway to be used. We briefed the Runway 01L approach and continued on. Then we were assigned to descent 9;000 feet at 250 kts and started our descent. At this time ATIS has 350 at 23 gusting 32 for winds. So we were in moderate turbulence on our way down. Because of this turbulence as we were at around 9;000 feet; we continued to descent below the assigned altitude and from what I saw speed even went up 260 kts. I disconnected the autopilot to do some corrective action in order to get back to 9;000 feet and be on speed. At this time my First Officer was about to change to another approach frequency. He checked in with the new frequency; but never heard anything from approach regarding any speed or altitude deviation. We were then continued for the approach to Runway 01L. We were left too high and too fast; as we got closer to the runway; we couldn't slow down (glide slope was at 3.4 degrees) and approach control just decided to make us go-around for we were getting too close to the aircraft ahead of us. We did go around and were vectored back to Runway 01L and landed without any other incident. On final; airspeed was +/- 15 kts. I should have inquired approach right away for which runway they'll be assigning us. And should be more vigilant especially when wind conditions are moderated. Our approach was just not set up as it should be to be stable and be on speed; I should have queried approach control if I feel like they are giving us something that would make us unstable eventually.
Air carrier Captain reported speed and altitude deviations due to moderate turbulence combined with a late runway assignment resulted in unstabilized approach and a go-around at LAS airport.