LANDING GEAR

Question 1

What type of landing gear?

Answer 1

• electrically activated
• hydraulically operated
• fully retractable
• tricycle landing gear

Question 2

Normal operation

Answer 2

• electrically powered
• reversible hydraulic pump
• pump activated by a two-position gear selector

Question 3

Hydraulic pump operation

Answer 3

• when hydraulic pressure exerted in one direction the gear is retracted
• exerted in the other direction gear is extended
• hydraulic fluid moves from one side of each landing gear actuator to the other
• fluid moves the piston connected to an actuator rod

Question 4

Electrical limit switches

Answer 4

• stops the flow of current to the motor of the hydraulic pump

Question 5

How does the landing gear stay in place?

Answer 5

• spring assists in gear extension & locking the gear in the DOWN position
• when gear is down, the down-lock hooks engage
• springs maintain force on each hook to keep it locked

Question 6

MAX Speeds

Answer 6

Max extension: 140 KIAS
Max retraction: 109 KIAS
Max emergency extension: 100 KIAS

Question 7

Up & Down Limit Switches

Answer 7

• Main gear & nose gear has these switches
• this senses gear position
• depressed by the top of each landing gear trunnion (large metal support connected to strut) as gear retracts

Question 8

Squat Switch

Answer 8

• left & right main gears have it
• determines if the airplane is airborne or still on the ground
• on the ground switch is not depressed & in the air it becomes depressed
• prevent hydraulic pump from actuating when BATT MSTR ON

Question 9

Over-center join

Answer 9

• keeps the gear down in the event of a side-loaded landing

Question 10

Low Pressure Control

Answer 10

• 600 +/- 200 PSI
• pump fails to shut off when gear is being lowered, the valve will open up to prevent any damages

Question 11

High pressure control

Answer 11

• used if pressure switch fails to shut off pump during retraction
• 2400 +/- 200 PSI

Question 12

Restrictor

Answer 12

• shuts off pump

Question 13

Pressure switch

Answer 13

• maintains a given pressure

Question 14

Shuttle valve

Answer 14

• moves back & forth
• hydraulic pressure moves either side to allow pressure to move

Question 15

CHECK GEAR CAS

Answer 15

• gear not down & locked manifold pressure below 14 inches (one or two engines)
• gear selector UP when a/c on ground
• gear not down & locked wing flaps extended to 2nd or 3rd notch
• above/below 400 AGL

Question 16

Emergency extension

Answer 16

• design to extend in an event of hydraulic failure
• lost of hydraulic pressure, gravity will extend the gear
• releases the hydraulic pressure, falls freely

Question 17

Ground operations

Answer 17

• nose gear steerable 30 degrees either side
• gear centering spring (prevents shimmy tendencies)
• bungee assembly (dampens shocks/bumps)

Question 18

Thermal relief valve

Answer 18

• valve will open to receive pressure as a result of temperature and pressure changes as a/c climbs or descends