7,8,9 Test

Question 1

features of two axis autopilot

Answer 1

altitude hold
heading hold
NAV hold
Vertical NAV

Question 2

what is a flight director? what are its components

Answer 2

a flight director provides pilot with lateral and vertical steering commands

it consists of:
sensors
computer
controller
Loads (command bars and autopilot)

Question 3

what are the three vibration ranges

Answer 3

Low - less than 500Hz - Main rotor

Medium - 500 - 2000Hz - main rotor or airframe

High - above 2000Hz - tail rotor, driveshafts, engine

Question 4

types of vibrations

Answer 4

Lateral - out of balance condition. center of mass out of line from center of rotation. adjusted by balancing blades statically or dynamically

Vertical - out of track condition. blades are not producing equal amounts of lift. adjusted by changing pitch links or blade tabs

Question 5

static Vs dynamic balance

Answer 5

static - done on a work stand while blades are stationary

dynamic - done while blades are turning and installed on helicopter

Question 6

types of stability

Answer 6

dynamically stable - helicopter will return to its original position

Dynamically unstable - helicopter will not return to original position, oscillations will worsen.

helicopters are naturally unstable

Question 7

transmitted damage

Answer 7

damage as a result of something happening to a different part of the aircraft.

ex - main rotor strike, T/R drive shaft found bent

Question 8

what steps must be taken when carrying out a conditional inspection

Answer 8

follow inspection criteria layed out in the maintenance manual

make a record of the incident that required the inspection

record what has been inspected

record any observations / findings as a result of the inspection

Question 9

after a hard landing, what transmitted damage may occur

Answer 9

flexing or deformation in the tailboom and main rotor blades.

binding or damage in the main driveshaft

damage or loss of main rotor GB spike mount.

Question 10

what is HUMS

Answer 10

health and usage monitoring system. cameras installed to monitor blade track and vibrations and provide trend monitoring data

Question 11

methods of vibration reduction

Answer 11

main rotor weights dampen vibration before it reaches main rotor head

main GB mounting to reduce vibration transmitted to the airframe

Question 12

methods of stability control

Answer 12

stabilizer bars and dampers. bars control blades, swashplate controls bars.

stabilizer bars are gyroscopic to dampen sudden changes

Question 13

track adjustments

Answer 13

speed sensitive - vibration changes with forward airspeed. tab adjustment. up will cause blade to fly higher but cause more aerodynamic drag

non speed sensitive - consistent vibration. pitch link adjustment (shorter if possible)