B747 CHAPTER 49

49

1. APU HAS 4 STAGE COMP AND 2 STAGE TURB
2. START ALLOWED MAX 20000FT, PNEU FOR MAX 15000FT , ELEC HAS NO LIMIT
3. IN W/W REMOTE S/D PNL FOR S/D AND DISCH BOTTLE
4. FIRE S/D RELAY AND FAULT RELAY ARE IN P52(UNDER P4)
5. APU CONT RELAYS ARE IN P83 (AEC)
6. EXTING BOTTLE AND APU BAT ARE IN APU COMP
7. ELEC AND PNU CAN SUPP ABOVE 95%
8. INTERSTAGE VLV OPEN AT 95% (TO BLEED)
9. INLET DOOR POS:
                                    GND: FULLY OPEN
                                     FLT: 15 DEG
                                     OFF
10. APU COOLING S/O VLV ACTUATED BY CDP (7.5PSI) COZ S/D IF CLOGGED OR NOT 
      OPEN WHEN N> 95%
11. NO GEN COOL LIT ON IF FLOW LOSS IN GEN AND APB TRIP
12. A SURGE VLV USED TO SURGE EXTRA AIR DEPENDS ON DEMAND, CONT BY ETC 
     (ELEC CONT TURB), PNEU OP
13. APU DC FUEL PUMP OPERATES IF GND SRVC OFF (DC PUMP ON LIT )
14. APU FUEL S/O VLV IS ON AFT SPAR OF #2MAIN TANK
15. FUEL S/O VLV OPEN WINDING POWERED FROM HOT BUS
16. FUEL S/O VLV CAN OFF BY FIRE HANDLE AND MASTER SW
17. APU FUEL PUMP:
                                    DC: APU PUMP
                                    AC: AFT PUMP IN MAIN TANK2

18. APU BAT CHARGING CUT DURING START
19. MSW OFF SIMULATES FAULTS TO S/D
20. START IS LIM TO 60SEC AND 90SEC IN COLD SOCKS(BE 2 HR IN COLD AIR)
21. RESTART ALLOWED JUST 2 TIMES IN 1 HR AND 3 TIMES IN COLD SOCKS
22. FUEL SOLE VLV CUT AT 7%
23. IGN OFF AT 95%
24. STARTER CUT AT 50%
25. LOW OIL PRESS COZ AUTO S/D AFTER 10 SEC IF N>95%
26. HI OIL TEMP COZ S/D IMMEDIATELY
27. CIT SIG LOSS COZ S/D IF N< 95%
28. ETC IS IN APU COMP
29. A LOAD CONT VLV MODULATED BY ETC TO LOWER THE EGT
30. A METERING VLV OP BY TORQ MOTOR CONT BY ETC REGULATES FUEL DEP ON LOAD 31. SECONDARY NOZZLE SUPP WHEN DEMAND > 30%
32. HOUR METER ON AT 50%
33. BAT FEEDS 1000A MOMENTARILY IN START
34. APU ANTI ICE VLV POWERED FROM APU BAT, IT WILL OPEN BELOW 4°C
35. REMOTE S/D PNL IS IN R/H MAIN W/W
36. ETC IS IN APU COMPARTMENT
37. FCU CONT THE METERING VLV SEND FUEL TO FLOW DIVIDER