Chapter 4 - Finishing the Tail


Section 3 - Building the Rudder

Rudder Control Horn

This is preliminary information for the construction of the rudder control horn and its installation:

The flat pattern drawing for the rudder bellcrank is found here:

Rudder Control Horn Flat Panel Drawing 1:1

It is fabricated from a piece of 1/8" 6061T6 aluminum angle (ACS
03-48400 $3.90 a foot).

A picture of the completed part (maybe less NAS75 bearings):

A Photo of Chris' Rudder Horn

It is mounted on the forward side of the rudder spar using the lower
hinge rod bearing and an AN3 bolt.  The tab on the bellcrank points
down ( the AN3 bolt is below the hinge rod bearing).  A washer is not
used when installing the lower hinge rod bearing against the bellcrank
and the bellcrank has the hole through which the rod bearing mounts
counter sunk to insure all three rod bearing hinges line up.

There are four extra layers of carbon fiber wrapped around the leading
edge of the rudder at the lower hinge point. The foam needs to be dug
out a bit and the rudder spar needs to be raidused so that when the
outside layer of carbon fiber is applied there is no decernable height
difference in this area. The outside layer of carbon fiber needs to be
laid against these layers.  Micro the outside later, not between the
four layers and the outside skin. The four extra layers are 3 inches
tall, wrap around the rudder spar and extend 5 inches aft of the
rudder spar.

There are also two rudderstops on each side of the fuselage that
restrict the movement of the rudder past 30 degrees of deflection.  I
am still working on these.