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Flashcards in APU Deck (18):
1

The APU pull fuel from which fuel cell?

AFT

2

What is the average fuel burn rate for the APU?

Approximately 175 lbs per hour

3

What provides starting power for the APU and what pressure should it be during Pre-flight?

Utility Hydraulic Accumulator, 2600 psi

4

What drive shaft connects the APU to the Transmission?

Number 7

5

In addition to turning the accessory section of the trans mission the APU also provides _________ and that is control by the __________.

IPAS air, Load Control Valve

6

During an APU start, the _____ is closed, which closes off the APU bleed air port to the IPAS manifold. The Electronic Control Unit (ECU) opens the _____ when the APU reaches ___ Ng.

LCV, LCV, 95%

7

Normal PTO clutch engagement occurs at _____% APU speed. Cold weather (__°F read from the transmission temperature transducers) or main rotor speed above _______% Ng, PTO clutch engagement will automatically occur at _____% APU speed.

60%, 0 , 94-96%, 95%

8

When does the “on” light up on the APU start Button?

95% Ng

9

Do not operate the APU for more than ____ minutes at a main transmission oil temperature of ____°C. Shutdown APU to prevent damaging the transmission accessory gearbox.

5 , 120-130

10

APU compartment fire

(1) On Ground:
(a) APU — OFF.
(b) Illuminated APU FIRE button — Press and RDY light illuminates.
(c) FIRE DISCH button(s) — Press.

(2) In Flight:
(a) Illuminated APU FIRE button — Press and RDY light illuminates.
(b) FIRE DISCH button(s) — Press.
(c) LAND AS SOON AS POSSIBLE

11

Extended APU Ground Operations. During prolonged ground operations greater than __ minutes, observe XMSN TEMP 1 and XMSN TEMP 2 on the SYS page. If the temperatures exceed ______° C. The APU shall be shut down and allow the oil to cool for ____ minutes

30, 130, 30

12

APU Operating Limitations. APU operation is prohibited during normal flight. After a fault or aborted start, wait ___ seconds after APU has stopped before attempting another start. After___ consecutive start attempts, wait ___ minutes before third start attempt. No more than 3 start attempts are permitted in one hour.

30, 2, 20

13

Avoid prolonged operation at _________% NR with the APU running.

94-96% Nr

14

Do not operate the APU for more than __ minutes at a XMSN TEMP1 or 2 of ________° C.

5, 120-130

15

The APU consists of an ________powered driven APU boost pump which draws fuel from the _____ cell.

electrically, AFT

16

What is the purpose of the APU?

Drives the transmission accessory gear box and provides IPAS air.

17

To prevent accidental APU start during maintains what should be done.

The APU ECU PWR/START circuit breaker located on ELC2 should be pulled.

18

Is electrical power required for an APU start?

Yes, although the utility HYD ACC provide starting pressure, the APU fuel boost pump requires DC power to start.