Flight Crew Last 90 Days 179
Communication Breakdown; Time Pressure
ATC Issue All Types; Deviation - Track / Heading All Types; Deviation / Discrepancy - Procedural Clearance; Inflight Event / Encounter Weather / Turbulence
Air Traffic Control Issued Advisory / Alert; Air Traffic Control Issued New Clearance; Flight Crew Became Reoriented; Flight Crew Returned To Clearance
Human Factors; Weather
On arrival in to LAS there was a thunderstorm with virga and potential hail on the course near FUZZY. The Controller issued a descent to 11;000 FT. As we were descending we saw the need to deviate due to the downdraft; rain and possible hail while we were in VMC conditions and with the terrain in sight. Our radio transmission failed to let the Controller know we had the terrain in sight; which alarmed him. We were asked to contact the Approach Supervisor on the radio. We apologized for not having told him we had the terrain in sight.
During descent on the SUNST 3 Arrival into LAS; we were deviating for weather near the FUZZY Intersection. At the time; we were deviating in visual conditions and could clearly see higher terrain to the east of the FUZZY Intersection. Descending through 14;000 FT; I told ATC we were turning 'about 10 left for weather'. The pilot flying turned more like 40 degrees; and went out high right of descent; we may have caught ATC off guard and they issued us a low altitude alert to stop our descent and turn right. At no time did we get any alerts in the cockpit. As ATC was issuing the alert; we were already leveling off at 12;000 FT and turning back toward the STAR. I think I could have told ATC that we were VMC and also made sure I understood what the pilot flying was planning on doing. Had I expected more then a 10 degree turn I would have suggested that we turn right.
B737 flight crew reports deviating for weather during the SUNST 3 arrival to LAS without properly informing ATC of the magnitude of the deviation and the fact that they had the terrain in sight.