Date: 201408
Local time of day: 1201-1800
Location: ZZZ.Airport, US
Flight conditions: Marginal
Light: Daylight
Aircraft: Regional Jet 900 (CRJ900)
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Takeoff / Launch
ATC / advisory: TRACON ZZZ
Aircraft component: Hydraulic Fluid
Reporter organization: Air Carrier
Reporter function: Captain; Pilot Not Flying
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Anomaly: Aircraft Equipment Problem Less Severe; Ground Event / Encounter Other / Unknown
Detector: Automation Aircraft Other Automation; Person Flight Crew
When detected: In-flight
Result: Flight Crew Landed in Emergency Condition; Flight Crew Returned To Departure Airport; General Declared Emergency
Contributing factors: Aircraft; Human Factors
Primary problem: Aircraft

Narrative: Cleared for takeoff First Officer's (FO) leg. During takeoff roll; at about 20 knots; we got 'R REV INOP' caution message. As this did not affect the safety of flight; which is the minimum standard to abort a takeoff; I elected to continue. Soon after rotation on climbout; 'R REV INOP' extinguished and EDP 2A caution message appeared. There-after both messages would cycle on and off. At 1;000 AGL I transferred the radios to the FO and began referencing the QRH. 'EDP 2A' message now constant so I started with that; however during the QRH procedure we received 'HYD SYS 2 LO PRESS' message. After checking the synoptic page I could see that our hydraulic reservoir for system 2 was completely empty. This was obviously the root problem so I went to that checklist instead. A cursory glance at the checklist told us we would need to return to base. By now we were at 10;000 feet climbing to 13;000 feet. At this time we told departure we would have to return. Going through the checklist and referencing the hydraulic synoptic; we saw we had no available brake pressure in the Number 2 system. This restricted our landing weight according to the QRH; so we coordinated with ATC for box vectors to burn fuel and get lighter. We also noted we would have to land at Flaps 20. It was about this time we declared an emergency. Checklist complete we completed our climb check; then notified Dispatch of our troubles and need for re-release. I then notified the FA of our situation and time frame to landing. From ATC we requested and were given the longest runway. The rest of the approach proceeded without incident. I elected for my FO to fly the approach since I am a recent transfer to the 900 and he has over a thousand hours in the airframe. He did a fine job. We landed below our maximum permitted weight derived from the QRH and thereafter taxied to the gate. The inboard brakes got a bit hot; with the left inboard triggering a warning with a BTMS reading of 15.




Synopsis: CRJ900 Captain experiences an 'R REV INOP' caution message at 20 knots during takeoff and continues. After takeoff an 'EDP 2A' caution message appeared but before QRH procedures can be applied a 'HYD SYS 2 LO PRESS' message appears. From the hydraulic synoptic page the root cause of all the messages is determined to be loss of fluid in the number two system. An emergency is declared and the flight returns for landing at the maximum allowable landing weight.