Regional Jet 900 (CRJ900)
Flight Crew Air Transport Pilot (ATP)
Distraction
Deviation / Discrepancy - Procedural Published Material / Policy; Inflight Event / Encounter Unstabilized Approach; Inflight Event / Encounter Weather / Turbulence
Human Factors; Weather
During descent from cruise altitude through 10;000 feet altitude; a fast-moving cold front with rapidly developing thunderstorms was approaching the [destination] airport from the north and northwest. Approach control advised two aircraft in trail of us that they would likely not be able to get to the airport before a level 6 thunderstorm; just north of the airport; would arrive over the airfield. We were in the lead of the three aircraft and were cleared to descend to 4;000 feet. I was keeping best forward speed to arrive at the airport prior to the thunderstorms reaching the airfield. Strong thunderstorms were also forming west of the airport.  With thrust levers at idle; I deployed flight spoilers descending from 11;300 feet through 10;000 feet to slow quickly; as I had been keeping best forward speed in the descent while above 10;000 feet (approximately 300 knots KIAS). I selected the F/CTL (Flight Control) synoptic page on the EICAS control panel as an additional reminder that flight spoilers were deployed; in addition to keeping my hand on the flight spoiler lever. When stabilized at 250 knots and descending at approximately 2;000 fpm; I retracted the spoilers. As we descended; the sky was darkening quickly and the EICAS primary display intensity was becoming a very bright; distracting glare. I quickly dimmed the display lighting to reduce the glare; but the CRT display intensity control knob on ED 1 was full bright and not dimming with the DISPL rheostat on the center pedestal lighting panel. I noticed that FMS 1 display had blacked out; as was the EICAS secondary display; and I asked the first officer to 'fix my lighting' on ED 2. As I was asking him to adjust the lighting; the First Officer stated 'I just lost my FMS; you need to select green needles'. He had not yet corrected the display lighting on ED 2. Once cleared for the visual approach; I once again needed to slow quickly from 250 knots to configure for approach; having kept our speed up to arrive prior to the thunderstorms reaching the airfield. We configured; ran the before landing checklist; and I disconnected the autopilot reaching approximately three miles out on final. We had a very brief glidepath excursion; approximately one half dot below glideslope; for which I stated 'correcting' and quickly returned on glidepath with a visual backup from the PAPI.  At three hundred feet AGL; we received an EICAS caution message for FLT SPLR DEPLOY on ED 1. At that point the FO finally corrected the display lighting on ED 2 to where it could be viewed; and we saw the EICAS advisory message for FLT SPLR DEPLOY. Immediately upon viewing the FLT SPLR DEPLOY caution on ED 1; I retracted the flight spoilers. A missed approach would have taken us in close proximity or possibly into the severe weather approaching from the west; and another CB (cumulonimbus) cell was converging on the airport from the north. I elected to land from an otherwise stable approach; rather than execute a missed approach into approaching severe weather. If a missed approach had been performed; the airfield would have been closed by the CB closing in from the north; and we had no listed alternate. Due to the rapidly changing nature of the weather associated with the cold front; and with rapidly building thunderstorms which had not appeared prior to our departing; there was no requirement for a legal alternate.  The easiest explanation; from a management standpoint; would be to say 'pilot failed to follow standard operating procedures; violating two limitations for spoiler use and deployment' and 'failure to execute a missed approach from an unstable approach'. However; this low altitude spoiler deployment has consistently remained one of the most frequent [incident] report items at this airline. It is a design shortfall of the Bombardier CRJ spoiler system not to have a caution message to alert pilots PRIOR to violating either limitation.  Although each airline can determine their own criteria for astabilized approach; it is common in ICAO operations; to define a stabilized approach as being achieved by 1;000 feet HAT (height above terrain) in IMC; and for all flights to be stabilized by no lower than 500 feet HAT in VMC. The Bombardier CRJ EICAS FLT SPLR DEPLOY caution does not trigger until 300 feet AGL; after all stabilized approach criteria has been violated by flight spoilers deployment under any meteorological condition; before the caution message will alert pilots. This system needs to be corrected to alert pilots before descending below 1;000 feet AGL or slowing below Vref + 17 knots with spoilers deployed. I have; on several previous reports and direct communication with the former fleet manager; suggested a new callout and procedure be implemented to mitigate low altitude spoiler deployment. At 1;000 feet AGL; [procedure] currently requires the PM (Pilot Monitoring) to callout '1;000 feet'; and the PF (Pilot Flying) to then check his/her parameters and respond either 'stable' or 'correcting to stable'.  My recommendation; for more than two years; has been to change the PF response to the '1;000 feet' callout be 'Stable/Spoilers Retracted' and have the PF make a physical sweep forward on the flight spoiler lever to insure it is full forward/spoilers retracted position. The PM should be trained to look for FLT SPLR DEPLOY on EICAS secondary displays to insure spoilers have been stowed. If this becomes a habit pattern; through standard operating procedure; I believe low-altitude spoiler deployments will become rare. The Bombardier CRJ EICAS FLT SPLR DEPLOY caution does not trigger until 300 feet AGL; after all stabilized approach criteria has been violated by flight spoilers being deployed. This system needs to be corrected to alert pilots before descending below 1;000 feet AGL or before slowing below Vref + 17 knots with spoilers deployed.
[Report narrative contained no additional information.]
CRJ-900 flight crew reported an unstabilized approach while attempting to beat thunderstorms moving into the arrival airport.