Landing Gear

Question 1

Describe the pump used in the landing gear system.

Answer 1

Hydraulic pressure is provided by an electrically driven reversible hydraulic pump.

Question 2

There are two circuit breakers in the landing gear system:

Answer 2

one for the hydraulic pump, one for the control circuit

Question 3

How is the gear held up?

Answer 3

using hydraulic pressure in hydraulic actuators

Question 4

How is the gear held down?

Answer 4

remains locked in the down position using over-center brace and spring

Question 5

How long of a time delay before the hydraulic pump is disengaged?

Answer 5

after 30 seconds of continuous duration

Question 6

How slow will the pilot need to be to extend the emergency gear?

Answer 6

100 KIAS

Question 7

What are all the main components of the landing gear system?

Answer 7

The landing gear system on a BE76 is a retractable tricycle system that utilizes an electrically driven hydraulically actuated reversible pump. Its controlled by the control lever located inside the cockpit. When the lever is moved in the down position the three green position indicator lights illuminate once the gear is down and locked, the in transit light will be on in between the gear being up and down. A time delay relay will only allow the pump to run for a maximum of 30 seconds before shutting off the pump to prevent a malfunction. Its a hydraulic system, therefore when the pump is on and the lever has been moved up, hydraulic fluid will move through hydraulic lines to the bottom portion of the hydraulic actuators. The hydraulic fluid pushes the pistons inside the actuators upward and those pistons are connected directly to the wheels. There is an emergency gear tool located towards the bottom left of the pilot and its used to turn a pressure release valve located underneath the pilots seat. You turn it counterclockwise under 100 knots and pressure is released allowing the gear to freefall and lock in the extended position.