Hydraulics Main

Question 1

What do the main hyd pumps provide hyd pressure to

Answer 1

flight controls, apu, rescue hoist

Question 2

what does the utility hyd pump provide hyd px to

Answer 2

dome

Question 3

hyd system components

Answer 3

3 identical hyd pumps, 2 transfer modules, one utility module, 3 dual stage primary servos, 2 tail rotor servos, pilot assist servo assembly, apu accumulator, and the rescue hoist

Question 4

general pressure of the hyd system

Answer 4

3000 psi

Question 5

what component of hyd system is at a lower px

Answer 5

pitch and roll trim actuators in the pilot assist servo assembly which are at 1000 psi

Question 6

what kind of distribution system

Answer 6

dual isolation distribution system

Question 7

when will we get a hyd warning

Answer 7

when the hyd system is severely degraded as a result of several compound malfunctions in #1/#2 and back up sys

Question 8

what does the #1 pump power

Answer 8

1 pri servo and 1st stage of tail rotor servo

Question 9

what are the components of the #1 hyd sys

Answer 9

1 hyd pump, #1 xfer module, 1st stage pri servo, 1st stage tail rotor servo

Question 10

parts of the #1 hyd pump

Answer 10

px relief valve, bleed valve, px filter, return filter, automatic low level sensing switch

Question 11

how many PDIs per pump

Answer 11

2

Question 12

Of the 2 filters in the hydraulic pumps, which is bypassable

Answer 12

the return filter, the pressure filter will not be bypassed and allow bad fluid in

Question 13

what causes the #1 RSVR low caution

Answer 13

closing of the auto low level sensing switch

Question 14

purpose of the #1 transfer module

Answer 14

passes fluid from the #1 pump to the first stage pri servo and 1st stage tail servo, and in the event of loss of pressure of the #1 pump routes fluid from the back up pump

Question 15

1 transfer module components

Answer 15

transfer/shutoff valve, pressure switch, first stage pri shutoff valve, first stage tail rotor shut off valve

Question 16

What causes the #1 hyd pump caution

Answer 16

activation of the pressure switch in the #1 xfer module which also signals the LDI

Question 17

what does the #2 hyd system power

Answer 17

second stage primary servos, pilot assist servo assembly

Question 18

2 hyd sys components

Answer 18

2 hyd pump and xfer module, second stage pri servos, pilot assist servos

Question 19

where is the #2 pri servo shutoff valve

Answer 19

2 xfer module

Question 20

can we directly actuate the pilot assist servo shut off valve?

Answer 20

Kind of, not fully secured with just one button

Question 21

what does pressing the sas/boost push button secure

Answer 21

hyd pressure to the boost servos and SAS actuators

Question 22

what causes a pri servo press caution

Answer 22

at least one of the 3 pressure switches on that stage sense low px

Question 23

what does the back up hyd sys do

Answer 23

powers #1 and #2 hyd sys before rotor spin up, powers rescue hoist system, and recharges the accumulator, and provides redundancy

Question 24

SAR concern if the b/u pump is supplying power to 2nd stage T/r

Answer 24

priority valve may secure hyd power to the rescue hoist

Question 25

back up hyd sys components

Answer 25

back up hyd pump and utility module

Question 26

caution about b/u hyd pump cb?

Answer 26

if the b/u hyd pump cb is out and a condition exists that would cause it to turn on upon being reset, you must either secure ac power or remove that condition before resetting or it may damage the current limiters and cause you to lose all loads and the #1 ac pri bus

Question 27

difference between b/u hyd pump and other pumps

Answer 27

powered by ac motor not engines/transmission

Question 28

b/u hyd pump contains what to ease start up for electric motor

Answer 28

internal depressurizing valve

Question 29

time frames associated with b/u pump energization

Answer 29

4 seconds on APU or ext power .5 sec on main gen

Question 30

Weight on wheels B/U pump switch off, on, auto

Answer 30

off - pump will stay off on - if #1 and 2 are operating normal, it circulates fluid and maintains px in apu and rescue hoist auto - holds px in #1/2 systems (including second stage tail servo) if LDI requires

Question 31

Weight off wheel B/U pump switch off, on, auto

Answer 31

off/auto - auto maintains power in the #1/2 systems if required by LDI - will also hold px second stage if tail servo sw placed in backup on - if other pumps operating normally, circulates flyid and maintains px in apu accum and rescue hoist

Question 32

how long minimum will the b/u pump operate if apu accum low

Answer 32

90 sec 180 if winterization kit is installed

Question 33

What will automatically turn on the b/u pump

Answer 33

#1 HYD pump (aka loss of px) #2 HYD pump (aka loss of px) #1 RSVR low #1 Tail RTR servo (aka loss of px)

Question 34

what does the utility module do

Answer 34

routes fluid to #1/2 xfer modules, second stage tail servo, rescue hoist and apu accum. it also contains a px switch that indicates when the pump is on

Question 35

what is the purpose of the priority valve between the utility module and rescue hoist

Answer 35

restricts hyd fluid to rescue hoist if px goes below a prescribed level

Question 36

what is the purpose of the velocity fuse in the utility module

Answer 36

secures fluid flow to the apu accumulator if flow rate goes past limit

Question 37

first reaction of LDI if #1 rsvr low

Answer 37

assumes leak is in 1st stage tail rotor servo lines and secures the 1st stage tail servo

Question 38

first reaction of LDI if #2 rsvr low

Answer 38

assumes leak is in pilot assist servo assembly and secures hyd pressure to the assembly

Question 39

if a leak progresses from rsvr low to hyd pump caution, what does LDI do

Answer 39

reopens the valve it shutoff and relies on pilot to secure the affected pri servo

Question 40

5 requirements for a hyd leak test

Answer 40

AC power B/U hyd pump switch auto All rsvr's full Weight on wheels rotors engaged it tests all hyd circuitry except for xfer shuttle valve operation

Question 41

10 lights indicating successful hyd leak test

Answer 41

#1 rsvr low #2 rsvr low buck up rsvr low Back up pump on SAS boost servo off afcs degraded #1 tail rtr servo #2 tail rtr servo on master caution

Question 42

what doubles as the rotor brake rsvr?

Answer 42

coffee can

Question 43

components of utility hyd sys

Answer 43

hyd pump, rsvr manifold, main xmsn oil cooler, distribution sys

Question 44

px of utility hyd sys when off/on

Answer 44

1000/3000psi