Rotor systems

Question 1

4 subsystems of the main rotor

Answer 1

main rotor blades
hub
flight controls
bifilar vibration absorber

Question 2

what kind of rotor head to do we have

Answer 2

fully articulated

Question 3

purpose of the elastomeric bearings

Answer 3

allow blades to flap, lead, lag and have pitch changes

Question 4

purpose of dampers

Answer 4

restrain lead and lag absorb start loads

Question 5

what is the main rotor head supported by

Answer 5

main rotor shaft extension which is secured by the lower pressure plate and main shaft nut

Question 6

how do control inputs get to the rotor head from the stationary swashplate

Answer 6

to rotating swashplate then pitch control rods to the pitch change horns

Question 7

when to anti flap restraints come out

Answer 7

around 35% Nr

Question 8

when do droop stops come out

Answer 8

around 70% Nr

Question 9

when do droop stops go in

Answer 9

around 50% Nr

Question 10

describe the rotor blade

Answer 10

pressurized hollow spar, honeycomb core, outer skin, abrasion strips, electrothermal deice mats, removable swept back tip fairing

Question 11

purpose of the swept back tip fairings

Answer 11

sound attenuation and efficiency

Question 12

angle of swept back blade fairings

Answer 12

20 degrees

Question 13

purpose of the electrothermal mat

Answer 13

allow for deicing of controls

Question 14

purpose of abrasion strips

Answer 14

extend useful life of blades

Question 15

what is the main rotor blade pressurized with

Answer 15

Nitrogen

Question 16

how do we know if structural integrity of blade spar is in question

Answer 16

Black on BIM

Question 17

what side of the aircraft are the tail rotors on

Answer 17

right

Question 18

angle of tail rotor upward

Answer 18

20 deg

Question 19

how much of the total lifting force in a hover does the tail provide

Answer 19

2.5%

Question 20

what does the tail rotor quadrant do

Answer 20

transmits rotor cable movements to the tail servo

Question 21

what happens if one tail cable breaks

Answer 21

the other cable is operated against spring tension and should provide normal responses

Question 22

what happens if both tail cables break

Answer 22

springs put the servo in a setting reflecting an approximate mid position collective setting spot

Question 23

how are the tail blades held on

Answer 23

sandwiched between two plates

Question 24

describe the tail blades

Answer 24

two composite spars that are completely interchangeable
they have abrasion strips and electrothermal blankets for deicing

Question 25

components of rotor brake sys

Answer 25

reservoir, master cylinder, gauge, relief valve assembly, accumulator, pressure switch, brake assembly, disc

Question 26

purpose of back pressure spring in rotor brake system

Answer 26

holds pressure on rotor break in case of limited leak

Question 27

where is the brake disc

Answer 27

on tail drive shaft output of MGB

Question 28

purpose of the gust lock switch

Answer 28

main purpose is to support auto blade fold by locking it in a position and is also a mild redundancy to the rotor brake while the blades are spread

Question 29

how long should you hold the gust lock switch minimum

Answer 29

5 seconds

Question 30

AVCS components

Answer 30

AVCC
10 feedback accelerometers
Vibe control actuation system which has and electronics unit and 5 force generators

Question 31

how long is the AVCS vibe nulling cycle

Answer 31

5 minutes

Question 32

can you initiate AVCS IBIT with rotors static

Answer 32

yes

Question 33

can you initiate AVCS IBIT with rotors spinning

Answer 33

shall not