PSA Airlines Canadair Regional Jet Systems (PSA-CRJ) Practice Exam

What conditions are necessary for hydraulic pump 1B and 2B to operate during flight?

1. Respective bus powered

2. Flaps out of 0 degrees

3. Any generator online

4. All of the above

The correct answer is: All of the above

For hydraulic pump 1B and 2B to operate during flight, several conditions need to be satisfied, which include all the elements mentioned in the options. First, both hydraulic pumps must be powered through their respective buses. This is crucial as without proper electrical power, the pumps cannot function. Each pump relies on its respective bus to ensure that adequate power is supplied for operation. Next, having the flaps extended beyond 0 degrees also facilitates the operation of the hydraulic pumps. The deployment of flaps requires hydraulic power to move the flap actuators, and when flaps are in any position other than fully retracted (0 degrees), it triggers the need for hydraulic assistance, thus enabling pump operation. Additionally, having any generator online is essential since it provides the necessary electrical power to the aircraft systems, including the hydraulic pump systems. When a generator is operational, it helps to ensure that the hydraulic pumps have a reliable power source available to them. Since all these conditions must be met simultaneously for proper operation of hydraulic pumps 1B and 2B during flight, the correct answer encompasses all these factors. Therefore, "All of the above" is the right choice as each of these conditions contributes to the functionality of the hydraulic system during flight.