Regional Jet 200 ER/LR (CRJ200)
Flight Crew Air Transport Pilot (ATP)
Communication Breakdown; Distraction; Time Pressure; Workload
Aircraft Equipment Problem Critical; Deviation / Discrepancy - Procedural Published Material / Policy
General Declared Emergency
Aircraft; Human Factors
We had received 14th stage Bleed Air Duct warning; were operating with wings and cowls selected off and had closed the left 14th stage bleed IAW the QRH.  Continued the QRH and landed with the Left engine at idle.  We did Declare an Emergency.  Because of where the event began; passing 21;000 FT; we were very busy running checklists and preparing for the approach.  We finally completed all checklists and the approach briefing at approximately 4;000 feet on a five mile base for the runway.During the post flight discussion with the crew; the Flight Attendant noted that we had failed to provide the signal for descent through 10;000 FT.  It seems that we omitted this step due to task saturation.  This is an easy miss as the cabin advisory is no longer a checklist item.  This 10;000 FT signal seems to be omitted fairly regularly and is especially likely to be omitted during an abnormal event.  This problem could be alleviated if we reinstated the cabin notification in the Descent and Approach Checklist.
Preoccupied with abnormal procedures generated by a bleed air duct temperature warning; the Flight Crew of a CRJ-200 failed to broadcast the alert to the Flight Attendants as they passed through 10;000 FT MSL as required by their company SOP.