Transmission

Question 1

powertrain components

Answer 1

Main xmsn modules, tail drives shaft, oil cooler, IGB, TGB

Question 2

what are the tail drive shafts suspended by

Answer 2

viscous damped bearings

Question 3

what is the built in tilt of the MGB

Answer 3

3 degrees forward

Question 4

5 modules of the main transmission

Answer 4

2 accessory modules
2 input modules
main module

Question 5

oil system of main xmsn

Answer 5

pressure lubricated wet sump
has
oil sump
bypassable oil filter
oil T and Px sensors
chip detectors

Question 6

purpose of the freewheeling unit and where is it

Answer 6

decouples Np and Nr ie decouples engines from xmsn for autos

Question 7

what does the input module do

Answer 7

transfers power from eng to MGB, supports the front of the engine, and first gear reduction

Question 8

purpose of the diaphragm coupling

Answer 8

connects output shaft to input module and allows for slight angular or axial misalignment

Question 9

where is the accessory module located

Answer 9

front of each input module

Question 10

purpose of accessory module

Answer 10

mounting and drive for ac generator and hyd pump module

Question 11

where is Nr measured

Answer 11

sensor on right accessory module of vertical instruments
sensor of left accessory module for TDI

Question 12

where is the main transmission low oil pressure sensor

Answer 12

left accessory module

Question 13

how are the IGB and TGBs lubricated

Answer 13

splash type

Question 14

function of the TGB

Answer 14

mounts tail rotor
changes angle of drive
provides gear reduction

Question 15

built in tilt of TGB

Answer 15

20 def left

Question 16

how does oil make its way through the main xmsn system

Answer 16

goes from sump to pump to oil filter to air/oil cooler to Px and T sensors through input mods to accessory modules accessory chip detectors input chip detectors then main gearbox with its chip detector

Question 17

is a popped MGB PDI indicative of a lubrication system malfunction

Answer 17

no just that mx is required after the last flight of the day

Question 18

thermal lockout on oil filter PDI purpose

Answer 18

so it wont pop on cold starts

Question 19

how is the oil cooler blower powered

Answer 19

via tail drives shaft

Question 20

when does the main xmsn press low caution come on

Answer 20

when the sensor on the left accessory module reads 14 PSI not the indication on the VIDS

Question 21

where are cockpit xmsn oil pressure readings taken from

Answer 21

MGB manifold inlet after cooler

Question 22

when does the main xmsn oil hot caution appear

Answer 22

when the sensor at the oil cooler input to the MGB manifold hits 117 deg C

Question 23

where are cockpit xmsn oil temperature readings from

Answer 23

temp sensor in the main module sump chip detector

Question 24

when do we get a main xmsn hot advisory (white)

Answer 24

when VIDS is above 105 but we don’t have the caution yet

Question 25

when do we get main xmsn press low advisory (white)

Answer 25

when VIDS is less than or equal to 30 PSI and Nr is greater than or equal to 25% and we don’t have the caution

Question 26

when do we get main xmsn press hi caution

Answer 26

VIDS over 130 PSI

Question 27

when do we get the main xmsn press hi advisory

Answer 27

VIDS over 65 but below 130

Question 28

how many chip detectors are in the main transmission

Answer 28

5

Question 29

do all the main xmsn chip detectors have burn off feature

Answer 29

yes

Question 30

when does the chip detector burnoff feature in the main xmsn deactivate

Answer 30

above 140 c

Question 31

what is unique about the main module chip detector

Answer 31

it has an embedded T sensor and has a 30 second delay on indications

Question 32

when will the chip detectors in the IGB and TGB indicate hot

Answer 32

140 C