MD-11
Flight Crew Instrument; Flight Crew Multiengine; Flight Crew Air Transport Pilot (ATP)
Aircraft Equipment Problem Less Severe; Deviation - Track / Heading All Types; Inflight Event / Encounter Weather / Turbulence
Flight Crew Returned To Clearance; Flight Crew FLC Overrode Automation; Flight Crew Overcame Equipment Problem
Aircraft; Weather
ATC assigned [us to] descend to 8;000 ft; reduce airspeed to 210 K. I deployed the spoilers and aircraft began an immediate left turn; we were navigating straight ahead. I disconnected the Auto Pilot and the aircraft immediately rolled into a left 45 degree bank; I stowed the spoilers and proceeded to turn back right; but not before we turned approximately 40-50 degrees left from our initial heading. ATC asked about our heading; and we advised asymmetric deployment of spoilers. Upon landing no spoiler deployment on the right side according to the configuration page. We wrote the problem up and Maintenance could not duplicate; we suspect the spoilers were frozen; it was light mist at departure airport.We are assuming the spoilers were frozen due to precipitation at the departure airport.That would be Flight Operations issue as there is very little a crew can do to prevent frozen spoilers in-flight.
MD11 Captain reported encountering an asymmetric spoiler issue during descent. Captain stated the spoilers may have been 'frozen' due to precipitation at departure airport.