Right System Failure - Loss of Pressure and/or Fluid
This is a work in progress
The right hydraulic pressure is less than 2349 PSI or greater than 3449 PSI or indicated hydraulic fluid quantity is less than 0.3 gal.
- Aircraft Operating Envelope: Maximum speed reduced to 285 KCAS / 0.90M maximum.
- Inboard Spoilers: Inoperative.
- Outboard Brakes: Accumulator pressure only.
- PTU: Inoperative.
- Right Thrust Reverser: Inoperative.
- Airspeed . . . 285 KCAS / 0.90M maximum
- Hydraulic Synoptic / Quantity . . . Check
- If the hydraulic failure occurred within 2 hours of takeoff:
- Airplane . . . Land at nearest suitable airport no more than 4 hours after the hydraulic failure
- If hydraulic failure did not occur within 2 hours of takeoff:
- Airplane . . . Land as soon as practicable
- PTU . . . NOT ARMED / OFF
- Brake Accumulator Pressure . . . Check
- If Right brake accumulator pressure is below 2000 psi:
- Brakes / Steering . . . As required to maintain directional control
- Thrust Reverser (Left) . . . As required
IF A HYDRAULIC SYSTEM FAILURE OCCURS WITHIN 2 HOURS AFTER TAKEOFF, LAND AT THE NEAREST SUITABLE AIRPORT NO MORE THAN 4 HOURS AFTER THE FAILURE OCCURRED. CONTINUING FLIGHT IN EXCESS OF 4 HOURS COULD RESULT IN A FLIGHT CONTROL SURFACE FAILURE, AND A LOSS OF AIRCRAFT CONTROL.
I am told that this is because the hydraulic fluid gets hot during takeoff and takes four hours to cool. If it has less than that and is just sitting stagnant in the lines, it is apt to rupture a seam or fitting and leak.
Hydraulic fluid temperature has stabilized, and flight control surface failure is not a concern.
(1) Landing Distance . . . Recalculate with 1.25 factor
The outboard brake accumulator pressure will not be replenished. When the outboard brake accumulator pressure is depleted, continued operation and braking will be performed only with the inboard brakes.
Gulfstream GVII-G500 Airplane Flight Manual, Revision 1, August 31, 2018