ATA 64 & 65 - Tail Rotor & Tail Rotor Drive

Question 1

How many blades on the TR fan?

Answer 1

10 unevenly spaced

Question 2

What is the nominal speed of the TR?

Answer 2

3122 RPM

Question 3

What is the rotor diameter for the TR blades?

Answer 3

1.15m

Question 4

What is the purpose of the Torlon bearings?

Answer 4

to guide the the TR blades

Question 5

Where can the balance screws be found on the TR hub?

Answer 5

Looking from the rear, on the L/H side.

Question 6

How is TR RPM sensed?

Answer 6

By a perminantly installed MAG PICK-UP

Question 7

If either RPM sensor fails, what advisory will illuminate?

Answer 7

NR SENSOR

Question 8

What are the TR blades made from?

Answer 8

Carbon Fibre with an outer layer of glass fibre and a hard foam core.

Question 9

When installing the TR hub fairing, what must be adhered to?

Answer 9

Aligning the red marks as the fairing is pre-balanced.

Question 10

How is the Fenestrom balanced?

Answer 10

by using the MAG pick-up and installing an accelerometer.

Question 11

What are the conditions required to measure the unbalance of the Fenestron during a ground run?

Answer 11

• Engine start switches in flight position and flat pitch.
• Control pedals in parallel position.
• Collective lever adjusted to FLI 2.5–3.
• AFCS/SAS switched OFF.

Question 12

What is the exeedance IPS for a TR unbalance?

Answer 12

1.0IPS

Question 13

How many driveshafts are on the H145?

Answer 13

Three - Two identical Fore & Aft, and one long DS in the middle

Question 14

How many bearings support ther Long DS?

Answer 14

4

Question 15

What are the Fore & Aft DS’s made from?

Answer 15

Carbon fibre with a final layer of glass fibre

Question 16

Why are Flexible Disk Packs installed?

Answer 16

To permit minor radial loads.

Question 17

Why are the flex disks arranged with a 60 degree offset to the preceding disk?

Answer 17

In order to prevent any deficiencies in strength

Question 18

What is the Long DS made from?

Answer 18

Steel

Question 19

What is the connecting adapter at the end of the Long DS made from?

Answer 19

Titanium

Question 20

What type are the bearings that support the Long DS?

Answer 20

Ceramic Roller bearings

Question 21

What is the purpose of the close fit rubber sleeve between the Long DS and TRDS bearings inner race?

Answer 21

They dampen vibrations, compensate a potential misalignment, and in
case of a bearing seizing, they allow the TRDS to carry on turning.

Question 22

What is the gear ratio of the TRGB?

Answer 22

1:30

Question 23

What is the oil quantity of the TRGB?

Answer 23

0.75l

Question 24

What esnures the lubrication of the control module bearings in the TRGB?

Answer 24

a collector tray.

Question 25

The setting shim is part of which component?

Answer 25

The control module.

Question 26

What type of lubrication system is the TRGB?

Answer 26

a wet sump lubrication system

Question 27

What material is the bigger left hand TR transmission fairing made from?

Answer 27

Carbon Fibre

Question 28

Continuity testing is the only type done on the TR. True or false?

Answer 28

True