Hydraulics

Question 1

Which systems are powered by HYDR 1?

Answer 1

Singal source: {#1 thrust reverser}, center AP,
nose & body gear steering/actuation,
inboard TE flap, left outboard elevator.
Dual source: Left aileron, left inboard elevator,
upper rudder, primary alternate brakes.

Question 2

Which systems are powered by HYDR 4?

Answer 2

Singal source: {#4 thrust reverser}, wing gear
actuation, spoilers 5,6,7,8, outboard TE flap,
right outboard elevator, normal brakes.
Dual source: Right ailron, right inbound elevator,
lower rudder (with system 2).

Question 3

Which systems are powered by HYDR 2?

Answer 3

Singal source: {Lower yaw damper}, right AP,
spoilers 2,3,10,11.
Dual source: Stabliser trim, elevator feel.

Question 4

Which systems are powered by HYDR 3?

Answer 4

Singal source: {Upper yaw damper}, left AP,
spoilers 1,4,9,12.
Dual source: Stabliser trim, elevator feel.

Question 5

How is demand pump 1 powered?

Answer 5

Pneumatically.

Question 6

How is demand pump 2 powered?

Answer 6

Electrically.

Question 7

Is there a shutoff valve for the demand pump(s)?

Answer 7

No, a control switch but no valve.

Question 8

With demand pumps 1 & 4 selected to AUTO under what conditions will they operate?

Answer 8

Flap in trnasit or out of UP, respective EDP output pressure low and/or respective FUEL CONTROL switch in CUTOFF.

Question 9

What will cause the HYDR SYS FAULT light to illuminate?

Answer 9

1. Low hydr system pressure.
2. Low hydr reservior quantity.
3. Excessive hydr fluid temprature.

Question 10

What will cause the DEMAND pump PRESS light to illuminate?

Answer 10

1. DEMAND pump selector to OFF or AUX.
2. Output pressure is low with the pump
   operating.
3. DEMAND pump fails to operate.

Question 11

With the loss of HYDR SYS 4, how is the landing gear and flap lowered?

Answer 11

ALTN GEAR EXTN switch and secondary (electrical) mode for flap.

Question 12

With the loss of HYDR SYS 4, does AUTOBRAKE & anti-skid operate?

Answer 12

AUTOBRAKE - No.
Anti-skid - Yes but only in pairs.

Question 13

What may cause the nose to pitch up on landing with the loss of HYDR SYS 4?

Answer 13

Rapid extention of spoilers. Spoiler panels 5,6,7,8 (4 inboards) will not deploy on touchdown.

Question 14

What is the difference between the normal & alternate braking systems?

Answer 14

Normal brakes: Autobrakes available &
individual wheel anti-skid protection.
Alternate brakes: No autobrakes & lateral wheel
pair anti-skid protection.