Narrative:

Approximately 30-35 minutes out (if a normal arrival had taken place) while relaying what I learned from my recent rft loft to the first officer; I checked the hydraulic synoptic page. We noted immediately the hydraulic system 3 quantity was low at 20%. We monitored the page and about 5-10 minutes later it had decreased to 15%. We then communicated with ATC that we had a hydraulic issue and requested priority handling. We also contacted dispatch and maintenance via radio. When discussing the situation with maintenance; the quantity had dropped to 10%. At that time; we also requested airport rescue and fire fighting; if required; and declared an emergency. I believe the emergency was declared with center. During this time; I made a couple of announcements to the passengers of our situation; and informed the flight attendants to prepare for a yellow emergency landing without any anticipated evacuation. About 10 miles from the airport; the quantity had dropped to 5% and the system pressure started to decrease. On downwind vectors; we attempted; unsuccessfully; to lower our gear normally. At that time; the hydraulic 3 lo press caution message illuminated. We requested vectors from approach and completed the non-normal checklist (taking approximately 15 more minutes); which allowed us to lower the gear successfully using the manual gear handle. We landed without incident with the flaps at 20 degrees per the checklist. Since nosewheel steering would not be available after landing; we requested in advance from dispatch that we needed a tow crew. After bringing the aircraft to a complete stop; I held the brakes and received an ok from the airport rescue and fire fighting crew. The aircraft was shutdown after the tug was hooked up and the APU was started; and then towed back to the gate. Of interest during the non-normal checklist for hydraulic 3 lo press in the pom: it states 'if ib ground splrs and ib brake press caution messages are on: no action required'. During the situation; our ib brake pressure was still at 2800 psi and the I brake press caution was not illuminated. However; the ib ground splrs caution was illuminated. We reviewed the ib ground splrs non-normal checklist. It called for switching the ground lift dumping switch to man disarm in-flight; then moving the switch to man arm upon landing; and adding a landing distance factor (ldf) of 1.25. Since the ib ground spoilers were inoperative due to low pressure on hydraulic system 3; and the ldf for hydraulic 3 lo press (1.70) has a note stating the ldf is 'based on the loss of the inboard ground spoilers and inboard brakes'; and the ob (outboard) ground spoilers were still operative; I decided the ib ground splrs non-normal checklist did not apply in this situation. I feel it was the safest and most prudent decision. However; I believe the checklist for hydraulic 3 lo press should read; 'if ib ground splrs and/or ib brake press caution messages are on: no action required for the individual messages' or something close to that verbiage.

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Original NASA ASRS Text

Title: A CRJ900 Captain declared an emergency prior to landing for a Hydraulic System 3 Fluid loss caused by a balance relief valve failure. After landing a pilot handbook procedure for GND SPLRS lead to some confusion and the reporter offered a suggested change.

Narrative: Approximately 30-35 minutes out (if a normal arrival had taken place) while relaying what I learned from my recent RFT Loft to the First Officer; I checked the hydraulic synoptic page. We noted immediately the hydraulic system 3 quantity was low at 20%. We monitored the page and about 5-10 minutes later it had decreased to 15%. We then communicated with ATC that we had a hydraulic issue and requested priority handling. We also contacted Dispatch and Maintenance via radio. When discussing the situation with Maintenance; the quantity had dropped to 10%. At that time; we also requested Airport Rescue and Fire Fighting; if required; and declared an emergency. I believe the emergency was declared with Center. During this time; I made a couple of announcements to the passengers of our situation; and informed the flight attendants to prepare for a yellow emergency landing without any anticipated evacuation. About 10 miles from the airport; the quantity had dropped to 5% and the system pressure started to decrease. On downwind vectors; we attempted; unsuccessfully; to lower our gear normally. At that time; the HYD 3 LO PRESS caution message illuminated. We requested vectors from Approach and completed the non-normal checklist (taking approximately 15 more minutes); which allowed us to lower the gear successfully using the manual gear handle. We landed without incident with the flaps at 20 degrees per the checklist. Since nosewheel steering would not be available after landing; we requested in advance from Dispatch that we needed a tow crew. After bringing the aircraft to a complete stop; I held the brakes and received an OK from the Airport Rescue and Fire Fighting crew. The aircraft was shutdown after the tug was hooked up and the APU was started; and then towed back to the gate. Of interest during the non-normal checklist for HYD 3 LO PRESS in the POM: it states 'if IB GND SPLRS and IB BRAKE PRESS caution messages are on: no action required'. During the situation; our IB brake pressure was still at 2800 psi and the I BRAKE PRESS caution was not illuminated. However; the IB GND SPLRS caution was illuminated. We reviewed the IB GND SPLRS non-normal checklist. It called for switching the GND LIFT DUMPING switch to MAN DISARM in-flight; then moving the switch to MAN ARM upon landing; and adding a landing distance factor (LDF) of 1.25. Since the IB ground spoilers were inoperative due to low pressure on hydraulic system 3; and the LDF for HYD 3 LO PRESS (1.70) has a note stating the LDF is 'based on the loss of the inboard ground spoilers and inboard brakes'; and the OB (outboard) ground spoilers were still operative; I decided the IB GND SPLRS non-normal checklist did not apply in this situation. I feel it was the safest and most prudent decision. However; I believe the checklist for HYD 3 LO PRESS should read; 'If IB GND SPLRS and/or IB BRAKE PRESS caution messages are on: no action required for the individual messages' or something close to that verbiage.

Data retrieved from NASA's ASRS site as of April 2012 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.