Regional Jet 700 ER/LR (CRJ700)
Troubleshooting; Human-Machine Interface; Workload; Communication Breakdown; Distraction
Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural Other / Unknown
Aircraft Equipment Problem Dissipated; Flight Crew Overcame Equipment Problem; Flight Crew Became Reoriented; Flight Crew Took Evasive Action
Aircraft
Climbing out at about 15;000 FT a 'Stall Fail' caution message illuminated. We continued our climb and ran the appropriate QRH procedure. Passing through FL310 the stick shaker began which disengaged the autopilot. We continued our climb while we addressed the problem and received a clearance from Center at the time to maintain a block altitude of FL310-340. We were able to get the autopilot reengaged only to have it be kicked back off by the stick shaker a few more times. The stick shaker was on continuously at one point for around 5 minutes. With the autopilot off above FL290 we were in RVSM without an RVSM equipped aircraft. The shaker and low airspeed cues on my PFD went away through around FL330 at which point we were able to reengage the autopilot; climb and maintain FL340 and continue to our destination with no more problems. The root cause was the maintenance issue with the 'Stall Fail' caution. The QRH procedure was run and double checked. ATC granted us a block altitude within RVSM. We were able to maintain positive control of the aircraft at all times and the extra altitude and time afforded us by being higher allowed us more time to troubleshoot if things continued to deteriorate. As the pilot not flying I could have vocalized the invalid low speed awareness cues that I was seeing on my PFD and which I assumed the Captain was seeing as well; but apparently was not; that would have provided more of a warning to him of the stick shaker. Assuming that the Captain had the same indications on his PFD was a mistake. I could have increased communication on my part and possibly given more warning of the stick shaker. Other than that I believe we handled it well; the block altitude was requested and granted to us while we troubleshot the problem. If we were not able to reengage the autopilot or the block altitude was not granted we would have descended out of RVSM airspace.
A CRJ700's STALL FAIL caution alerted climbing through 15;000 and the stick shaker began at FL310 which disengaged the autopilot so ATC issued a RVSM block altitude until the warning was overcome for normal flight.