B744 HYDRAULICS Flashcards
What are the main items powered by HYD SYS 1?
- Nose and Body Gear steering and actuation
- Inboard TE Flaps
- Left Outboard Elevator
- Alternate Brakes
- Center A/P
What are the main items powered by HYD SYS 2?
Stabilizer Trim
Elevator Feel
Alternate Brakes
Right A/P
What are the main items powered by HYD SYS 3?
Stabilizer Trim
Elevator Feel
Left A/P
What are the main items powered by HYD SYS 4?
Wing Gear actuation
Outboard TE Flaps
Primary Brakes
Right Outboard Elevator
What powers #1 Demand Pump?
Air (faster)
What powers #2 Demand Pump?
Elec (more torque)
Is there a shutoff valve for the Demand Pump?
NO; a switch but no valve
When do Demand Pumps 1 & 4 automatically operate?
- Flaps in Transit or out of UP
- respective Eng Driven pump output pressure low
- respective Fuel Control switch in CUTOFF
What will cause the HYD SYS Fault light to illuminate?
- Low Hyd system pressure
- Low Hyd reservoir qty
- Excessive Hyd fluid temperature
What will cause the Demand pump low PRESS light to illuminate?
- Demand pump selector to OFF or AUX
- Output pressure is low with pump operating
- Demand pump fails to operate
With loss of HYD SYS 4, how do you lower the Ldg Gear & Flaps?
ALTN Gear extend switches / Secondary mode (electrically)
With the loss of HYD SYS 4 do you have Autobrakes? Anti-Skid?
NO / YES (in pairs only)
What may cause the nose to pitch up on landing with loss of HYD SYS 4?
Rapid extension of Spoilers;
Spoiler panels 5,6,7, & 8 (4 inboards)
will not deploy on touchdown
What is the difference between Normal & Alternate brake systems?
- Normal brakes: Autobrakes available and individual wheel Antiskid protection
- Alternate brakes: No Autobrakes and all lateral wheel pairs Antiskid protection
