Appearance of the BOOST SERVO OFF caution indicates what?

Appearance of the BOOST SERVO OFF caution indicates what?

• A. Loss of Hydraulic Pressure to the Cyclic Servo
• B. Loss of Hydraulic Pressure to the Collective and/or Yaw Boost Servo
• C. Loss of Electrical Power to the Flight Computer
• D. Booster Pump Malfunction

Answer: (B)

BOOST SERVO OFF means hydraulic pressure has been lost to one or more of the boost servos that amplify pilot inputs for primary flight controls. In the UH-60, the collective and yaw (tail rotor) boost servos provide hydraulic assistance to those axes, making it easier to raise/lower the collective and to yaw the helicopter. When pressure to these servos is lost, you’ll feel an increase in control forces and a reduction in authority on those controls. The cyclic boost servo isn’t indicated by this warning, so its status doesn’t trigger this caution. This is why the appearance of the caution is best interpreted as a loss of hydraulic pressure to the collective and/or yaw boost servo, signaling you to expect heavier control effort and degraded yaw control and plan accordingly.

BOOST SERVO OFF means hydraulic pressure has been lost to one or more of the boost servos that amplify pilot inputs for primary flight controls. In the UH-60, the collective and yaw (tail rotor) boost servos provide hydraulic assistance to those axes, making it easier to raise/lower the collective and to yaw the helicopter. When pressure to these servos is lost, you’ll feel an increase in control forces and a reduction in authority on those controls. The cyclic boost servo isn’t indicated by this warning, so its status doesn’t trigger this caution. This is why the appearance of the caution is best interpreted as a loss of hydraulic pressure to the collective and/or yaw boost servo, signaling you to expect heavier control effort and degraded yaw control and plan accordingly.