What is the primary purpose of an accumulator in a helicopter's hydraulic system?

The primary purpose of an accumulator in a helicopter's hydraulic system is to store hydraulic fluid under pressure, providing a reserve of hydraulic power for various functions and dampening pressure fluctuations within the system. Hydraulic systems are used in helicopters to assist with flight controls and to power other systems, such as landing gear and rotor brake. These systems require a constant and reliable supply of hydraulic fluid at a specific pressure. The accumulator acts as a reservoir, storing hydraulic fluid that has been pressurized by the hydraulic pump. This stored pressure can be used to supplement the pump's output during periods of high demand, such as when making rapid control inputs or when the pump is temporarily unable to meet the system's demands. Additionally, the accumulator helps to absorb pressure surges and pulsations within the hydraulic system, preventing damage to components and ensuring smooth operation. Some accumulators can also provide a limited amount of hydraulic power in the event of a hydraulic pump failure, allowing the pilot to maintain control of the helicopter for a short period of time.