12.03 Blade Tracking

Question 1

Rotor tack methods(7)?

Answer 1

Pre-track method
Stick method
Flag method
Light reflector method
Electronic strobe method
Optical camera method
HUMS

Question 2

If you bend a trim tab up what happens to the blade attitude?

Answer 2

The blade goes up

Question 3

Low frequency vibrations?

Answer 3

0-500 cycles per minute

Question 4

Medium frequency vibrations?

Answer 4

500-2000 cycles per minute

Question 5

High frequency vibrations?

Answer 5

2000+ cycles per minute

Question 6

What do skids have to reduce vibrations?

Answer 6

Dampers

Question 7

Passive vibration absorber is made up of?

Answer 7

Weights that spin out when the head is turning to take up vibrations

Question 8

Active vibration absorbers?

Answer 8

A suite of accelerometers located at key positions around the aircraft there values are taken and 4 reactive actuators create opposite forces

Question 9

What type of main rotor head is ground resonance usually associated with?

Answer 9

Fully articulated

Question 10

How do you stop ground resonance?

Answer 10

Immediately take off or if that is not possible you must drop the collective and slam the rotor break on

Question 11

Which method is most widely used in vibration analysis?

Answer 11

Electronic balancer

Question 12

What does HUMS stand for ?

Answer 12

Health and Usage Monitoring System