Collective/Cyclic Combining Systems

Question 1

Interlink assembly

Answer 1

Installed to a cyclic system to automatically cancel unwanted effects of change of the collective lever.

When collective lever is lifted; the pitch of main rotor is increased, this puts nose of aircraft up.

Question 2

Interlink assembly

Answer 2

When you raise the collective an interlink assembly will push the cyclic forward a small amount to make sure the aircraft comes up level. This will also add a yaw input counter torque reaction.

Question 3

Constant rotor speed

Answer 3

The engine power output must be adjusted to compensate for the varying thrust demand.

Most helicopters have automatic devices that detect the smaller variation in rotor speed.

The add more fuel accordingly to keep the rotor speed the same.

Usually provided by a fuel computer or a hydro mechanical governor

Question 4

Powered control.

Answer 4

Hydraulic systems are required to provide sufficient force to operate the controls easier.

Hydraulically powered servo jacks are the way we achieve this.

Always on the lower swash plate (non rotating swash plate).

Question 5

Alternate ways to fly.

Answer 5

If hydraulics fail on the Gazelle, it refers to manual control where as on the lynx because it’s too heavy there has to be a backup hydraulic system in case the first one fails.