Hydraulic System
The projectmax C212 hydraulic system provides pressurized fluid to actuate the ramp/cargo door, flaps, normal/emergency/parking brakes, and nosewheel steering. A single electrically-driven variable-flow pump supplies the system at a nominal 2000 psi; a manual hand pump provides backup pressure if the electric pump or its power supply fails.
Components
| # | Component | Description |
|---|---|---|
| 1 | Reservoir | 7.8-liter capacity tank with a sight-glass level window (FULL/REFILL markings), fed by return lines from all subsystems. |
| 2 | Electric pump | Driven by an electric motor, controlled by the HYD PUMP switch on the overhead panel; delivers fluid at 2000 psi through a check valve and filter. |
| 3 | Manual hand pump lever | Mounted at the RH side of the C/M-2 seat; a double-acting pump usable if the electric pump or its power fails. A check valve prevents backflow through the electric pump while hand-pumping. |
| 4 | Relief valve | Protects the system from overpressure, relieving at 2350 psi. |
| 5 | Pressure sensor/indicator | Feeds the HYD pressure gauge on the central instrument panel (0–4000 psi, green arc 1850–2050 psi, red line at 2720 psi). |
Systems Served
| # | System | Operation |
|---|---|---|
| 1 | Ramp and cargo door | Opening/closing sequence via the CARGO DOORS CONTROL handle (OPEN/CLOSED). |
| 2 | Flaps | Extend/retract via the flap lever (UP/NORMAL/DOWN), each direction routing pressure to one side of the flap actuator. |
| 3 | Brakes | Normal braking is proportional/differential via brake pedals. |
| 4 | Nosewheel steering | Hydraulic actuator driven by the steering handwheel, with a low-pressure accumulator providing anti-shimmy damping. |
Failure Indications
Loss of pressure is not separately annunciated by a dedicated caution light beyond the low-reading gauge itself, but subsystem-specific effects appear: flaps stop responding to the lever, nosewheel steering stiffens/centers, and braking authority may be reduced until the accumulator(s) are depleted — at which point the manual hand pump becomes the crew’s recovery tool.