Systems - Part 2

The function of the reservoir in a hydraulic system is to?

• Cool the hydraulic fluid during operation.
• Filter contaminants from the hydraulic fluid.
• Receive and hold system fluid returning from components and to provide it at pressure to the inlet side of the hydraulic pump.

• Store hydraulic fluid and maintain system pressure.

How are reservoirs designed for high altitude flight? And how can the reservoir be pressurised on some aircraft?

• Reservoirs are designed with durable materials and insulation for low pressure; they can be pressurized using engine bleed air.
• Reservoirs are pressurised by bleed air from the compressor or pneumatic system pressure.

• They are usually pressurised for a positive flow of fluid to the pump at high altitude and low atmospheric pressure.

• They can only be pressurized using hydraulic fluid from the landing gear system.

What is the function of an accumulator in a hydraulic system?

• The function of an accumulator in a hydraulic system is to store energy, maintain pressure, and provide additional fluid flow when needed.

• To increase the weight of the aircraft for stability.
• To provide an emergency backup of fluid (reserve pressure) at near system pressure and to smooth out pressure fluctuations

• To cool the hydraulic fluid in the system.

What is the function of a bypass valve in a hydraulic system?

• To cool the hydraulic fluid before it enters the pump.
• To filter contaminants from the hydraulic fluid.
• To ensure the continued flow of hydraulic fluid if the filter becomes blocked

• To maintain pressure and flow in a hydraulic system by allowing fluid to bypass components.

What is the function of the pressure relief valve in a hydraulic system?

• To regulate the temperature of the hydraulic fluid.
• To filter contaminants from the hydraulic fluid.
• To open the valve allowing excess fluid to flow back to the reservoir and to heat the fuel to ensure the fuel doesn't approach its freezing temperature.

• To prevent excessive pressure buildup in the hydraulic system.

What is the function of the stand pipe in the hydraulic system?

• To cool the hydraulic fluid during operation.
• To maintain fluid level and prevent air entry in the hydraulic system.
• To ensure a supply of hydraulic fluid for the operation of the emergency hydraulic pump for a short time, should the main systems fluid supply become depleted.

• To increase pressure in the hydraulic system.

What is the function of a fuse in a hydraulic system?

• To increase the flow rate in the system.
• The function of a fuse in a hydraulic system is to protect against excessive pressure or electrical overload.
• To prevent the complete loss of hydraulic fluid if a leak develops in a component downstream of the fuse.

• To filter out impurities from the hydraulic fluid.

The basic design architecture of a typical large air transport aircraft hydraulic system is 3 completely independent systems. What happens if one of three fails?

• The aircraft can still operate safely with the remaining two hydraulic systems.
• The aircraft must land immediately regardless of the situation.
• All hydraulic systems will fail immediately.
• If one system fails, some of the components will experience degradation but not their complete loss.

What is the trend in hydraulic system designs?

• Increased reliability and efficiency with fly-by-wire technology.
• Reduced maintenance requirements with mechanical systems.
• Is toward higher system pressures to reduce component weight and total system fluid weight.

• Enhanced manual control with analog technology.

What is the force generated by a 2 square inch piston(ram) when 3000psi of hydraulic pressure is applied to it is?

• 12000 pounds
• 3000 pounds
• 6000 pounds
• 1500 pounds