Dash 8-100
Flight Crew Air Transport Pilot (ATP)
Aircraft Equipment Problem Critical
Flight Crew Rejected Takeoff; Flight Crew Returned To Gate; General Maintenance Action; General Flight Cancelled / Delayed
Aircraft
After receiving clearance to takeoff; we were taxiing into position and the First Officer completed the Before Takeoff Checklist below the line. As he was finishing the control check and I was lining up with the runway; the #1 'Hyd Iso' bulb caution light and the 'Roll Splr' HUD caution lights came on. We looked at the hydraulic gauges and the quantity of #1 was showing below 1 quart. We contacted Tower and said we were taxiing off the runway for maintenance. I brought the plane to a stop on the taxiway; stopped the plane and ran the checklist. I also called our Dispatcher and spoke to Maintenance. We determined we needed to get towed back to the gate; so I taxied the aircraft onto the ramp to expedite that process. Once at the gate Maintenance determined that the plane needed to be ferried; and we were swapped onto another aircraft to finish the flight. The inboard hydraulic actuator failed and was leaking; causing the loss of fluid.
While lining up for take-off; the crew of a DHC-8-102 noticed warning indications alerting them to a hydraulic system malfunction. Declining his take-off clearance; the Captain taxied clear of the runway onto the taxiway; and then to the ramp for inspection by Maintenance.