Q400
Flight Crew Air Transport Pilot (ATP)
Situational Awareness
Deviation - Speed All Types; Inflight Event / Encounter Weather / Turbulence
Flight Crew Became Reoriented
Human Factors; Weather
Aircraft was established on the ILS approach. Speed was 190 approximately and autopilot was engaged 3 miles prior to FAF where I commenced final configuration. We were flying in icing conditions with ice detected; so Np was 1020; ref speeds were increased; and solid bug speeds were to be used. I reduced power and commanded flaps 5; gear down; flaps 15 and finally flaps 35.As the speed decayed; the low speed cue did not reduce as rapidly as anticipated during each flap setting and the stick shaker activated. A recovery was initiated which kept us within approach tolerances and the approach was reestablished and continued to a successful landing.As flying pilot; I adopted my usual routine and technique of slowing the aircraft by setting power levers to flight idle prior to the FAF and commanding the flaps and gear through the normal sequence of 5; Gear; 15 and 35; then adding power to stabilize the speed at Vref.However; the conditions of the day (and my expectations established from previous approaches in more favorable conditions) were the perfect storm. Props 1020; increased ref speeds; actual light to moderate ice accumulation; and flight idle; all of which led to a much faster than anticipated speed reduction. This led to a situation where the speed decayed faster than the low speed cue retreated and resulted in a stick shaker. Primary cause would be my faulty expectations; which should have been modified to not reduce power so aggressively due to obviously adverse conditions.
A Q400 First Officer reported receiving a stick shaker on arrival when the aircraft slowed faster than expected while in icing conditions.