MOD 8 GEAR 9 BREAKS

Question 1

What gas, and what fluid are normally contained in an oleo type shock absorber?

Answer 1

Air/(N2), and hydraulic fluid

Question 2

What restricts the flow of fluid within the oleo?

Answer 2

Metering pin

Question 3

Describe the operation of a shock strut (oleo) and its internal components

Answer 3

The strut absorbs the landing impact as oil transfers from the oil chamber into the air chamber around the metering pin (or through a calibrated orifice) as the piston is forced into the cylinder by the weight of the aircraft. Taxi shocks are dampened by the compressed air in the air chamber.

Question 4

Explain the maintenance and servicing (initial/full) of a shock strut (oleo), in approximately 14 steps.

Answer 4

1. Clean around filler plug, 2. Jack aircraft, 3. Depressurize strut through charging/air valve, 4. Remove filler plug, 5. Compress strut fully, 6. Fill strut with appropriate hydraulic fluid, 7. Install filler plug, 8. Extend and compress strut several times to remove trapped air, 9. Remove filler plug, 10. Compress strut, 11. Ensure fluid level is satisfactory, 12. Install filler plug, 13. Remove aircraft from jacks, 14. Inflate strut to expose correct amount of piston tube

Question 5

When disassembling the strut what important safety precaution should be observed in regard to the scraper ring?

Answer 5

The scraper ring may wear sharp so use caution when handling and removing

Question 6

Should the air valve core be removed from the filler plug body when disassembling the strut or to remove the nitrogen pressure if the valve core assembly is not being replaced?

Answer 6

no

Question 7

When inflating the nose gear strut to test for leaks, what is the recommended inflation pressure?

Answer 7

65psi

Question 8

What are some causes of “spongy braking action”?

Answer 8

Air in the lines/ or deterioration of the flexible lines

Question 9

What is the advantage of the carbon brake? -Light weight, and can absorb tremendous amounts of heat. or -Inexpensive to replace.

Answer 9

Light weight, and can absorb tremendous amounts of heat.

Question 10

What caution should you be aware of when using a pressure pot to bleed a brake system?

Answer 10

Ensure you have the correct type of fluid.

Question 11

Breaks- What do we do in regards to leaking fluid line connections?

Answer 11

The fittings should be checked for the proper torque.

Question 12

Are modern single disk brakes self adjusting?

Answer 12

yes

Question 13

Why are their slots cut into the stationary disks in the multi disk brake setup?

Answer 13

To allow for expansion as the disk gets hot.

Question 14

Carbon brakes are primarily used on what type of aircraft?

Answer 14

Jet transport aircraft.

Question 15

General aviation aircraft are equipped with what type of brakes?

Answer 15

Single disk actuator, fixed disk type.

Question 16

Under normal foot braking conditions when the brakes are applied, does the fluid flow into the thermal relief valve piston area? yes or no

Answer 16

no

Question 17

When the park brake has been applied, can fluid flow back to the reservoir from the brake unit at the wheel? yes or no

Answer 17

no

Question 18

When the master cylinder is in the static position (brake and park brake in the off position) is the poppet valve in the piston head normally open or closed?

Answer 18

Opened

Question 19

When the park brake has been applied, can fluid flow from the reservoir to the master cylinder and into the chamber where the spring #10 is located? yes or no

Answer 19

yes

Question 20

Can fluid flow to or access the thermal relief piston from the brake unit at the wheel when the park brake is applied? yes or no

Answer 20

yes

Question 21

If poppet valve leaks slowly, when the brakes are applied what will happen? -the brake pedal will slowly bleed down and the brakes will release unless pumped up again or -brakes will lock on after application and stay locked on after foot pressure is released

Answer 21

the brake pedal will slowly bleed down and the brakes will release unless pumped up again

Question 22

Why must the brakes on this system be applied to release the park brake poppet valve? -to allow fluid to the brake to release the back pressure resisting assembly releasing the brake or -to equalize the pressure on both sides of the park brake poppet valve and allow the spring to open the park brake poppet valve allowing fluid flow from the brake unit

Answer 22

to equalize the pressure on both sides of the park brake poppet valve and allow the spring to open the park brake poppet valve allowing fluid flow from the brake unit

Question 23

what is 5 ,6 and 7

Answer 23

• 5. Pressure out to brake
• 6. Parking brake poppet valve
• 7. Thermal relief chamber

Question 24

Why bleed brakes ?

Answer 24

to prevent spongy braking action and restore the proper brake function

Question 25

what is 1 and 2

Answer 25

• 1. Piston rod
• 2. Poppet valve