Regional Jet 200 ER/LR (CRJ200)
Flight Crew Air Transport Pilot (ATP)
Distraction
Deviation - Speed All Types; Inflight Event / Encounter Weather / Turbulence
Flight Crew Became Reoriented
Human Factors; Weather
During turn to final approach we flew through an area of heavy rain. First Officer was flying pilot. I noticed a decrease in airspeed trend indication and told the First Officer to watch the airspeed. I then told the First Officer to increase power and had to repeat the command another time. We were in a turn and airspeed was around 170 to 180 KTS. As we continued; the airspeed dropped around 30 KTS; the autopilot disengaged and the stick shaker activated momentarily. The First Officer added full power momentarily and hand flew to intercept the inbound course. Airspeed returned to normal and we continued to landing. The turn; coupled with the down draft from the cell of heavy rain; increased the stall speed and at the same time the airspeed loss caused the stick shaker to activate momentarily which turned off the autopilot. I noticed this as it was occurring but I don't think the First Officer's situational awareness was where it should have been and he was slow to react. I had to prompt him several times to increase power. During the next flight sequence the First Officer stated he was going to call in fatigued. I received a call from the Chief Pilot after the return from the round trip that seemed to indicate that this incident may have been discussed in reference to the First Officer's decision to call in fatigued. As I was not involved with that discussion I do not know whether it was discussed or not. When I returned to the aircraft a new First Officer was present and the gate was asking us to board the aircraft. I had received the dispatch release on arrival from the inbound and it included the old First Officer's name on it. While we were boarding and setting up for the flight I actually noted to call Dispatch and change First Officer name on release but was in a high workload situation and answering loading questions and entering data into FMS; doing checklists etc. I did not contact Dispatch. During climb out I thought about the release and checked it; it was not changed with new First Officer name and number. I called Dispatch to do the change and continued the flight.
CRJ200 Captain describes an approach by his First Officer through heavy rain that gets down to stick shaker speed before sufficient thrust is added.