B747 CHAPTER 29

29

1. HYD POWER:
                       4 ADP (AIR DRIVEN PUMP)
                       4 EDP (ENG DRIVEN PUMP)
                       1 ACP USED FOR HYD4
                       STBY ON HYD1, PRESSURIZES HYD3
2. ALL HYD COMPONENTS ARE IN PYLON EXCEPT RETURN FILTER 2,3 AND STBY   
    PUMP
3. RETURN FILTER MODULE 2,3 ARE IN WING REAR SPAR
4. STBY PUMP IS IN STAB COMPARTMENT
5. HYD3 RETURN LINE USED AS RESERVOIR FOR STBY SYS (AND FEED HYD1)
6. HYD SERVICE STATION IS IN L/H BODY W/W
7. EDP IS AT R/H OF ENG CONN TO AGB
8. A PRESS RELIEFE VLV OPENED AT 3500 PSI
9. LOW PRESS SW OPERATE AT 1200 PSI FOR ADP AND EDP
10. HYD SYS PRESS LIT WILL ON IF BOTH ADP AND EDP LOW PRESS
11. ACP POWERED FROM GND HAND BUS, 115 VAC, 3 PHASE IS IN PYLON
12. LOW PRESS LIT MUST ON FOR ACP RUN
13. ADP SW:
                AUTO: WILL RUN IF EDP PRESS <2600 AND OFF >2800 PSI
                OFF: LOW PRESS LIT ON
                CONTINUOUS: MANUALLY ON
14. EDP SW:
                   NORM: FULL PRESS RUN
                   DEPRESS: SOLE ENER AND CLOSE BLOCK VLV TO BLOCK PUMP OUT
                   SUPP OFF: 2 MIN LIMITED
15. SUPP S/O VLV IS 28VDC CAN BE OFF BY EDP SW OR FIRE HANDLE
16. RESERVOIR 1,4 ARE 9.5 GALLON, AND 2,3 ARE 5.5
17. A QTY IND REPEATS THE SIGNAL OF IND FROM COCKPIT
18. OVERHEAT LIT WILL ON AT 104 °C AND OFF AT 80 °C
19. HEAT EXCHANG IS IN MAIN FUEL TANK
20. STBY SYS WILL FEED PITCH TRIM AND PITCH FEEL IF HYD3 FAIL