Dynon Avionics EFIS-D10A Installation Guide - Manual (Page 46)

Autopilot Installation and Configuration
6-6 EFIS-D10A Installation Guide
Note: As with the optional Dynon HS34, it is acceptable to connect the tone output of EFIS
(DB25 Pin 18) and/or EMS (DB37 Pin 31) in parallel with the tone/voice output of the AP74
(Pin 25) to provide “failover” audio alerts from the EFIS and/or EMS if the AP74 were to fail.
However, do not connect the audio outputs from an HS34 and AP74 in parallel.
Servo Mechanical Installation
Dynon Avionics has researched suitable mounting points for a number of popular aircraft and
offers mounting kits and instructions for them. If you have purchased one of these kits, use the
instructions included with it as your primary guide; the following mechanical installation
information is more general in nature.
For installing Dynon Avionics servos in aircraft for which Dynon does not offer kits, we offer a
“generic” kit of basic parts and basic installation instructions: Dynon P/N 101020-000. The
generic servo push-pull mounting kit includes some of the hardware to mount a servo and
connect to the aircraft controls, but requires the installer to fabricate mounting brackets. This kit
can be used in either pitch or roll applications that use a servo with an output arm (not suitable
for use with pulley/cable servos). Some additional fasteners (not supplied by Dynon) and
brackets will be required depending on the installation method chosen.
CAUTION: Neglecting to properly install and/or use Dynon Avionics AP hardware can
result in failures which could cause loss of aircraft control resulting in aircraft damage,
personal injury, or death. If there are any questions on the part of the installer it is
mandatory to resolve these questions prior to flight.
When installing the servo, you must first determine a mount location for proper interaction with
the existing control system. The mounting point that is chosen must allow the servo arm and
associated linkage to move freely through the entire range of travel. To prevent the possibility of
the servo arm going OVER CENTER, the servo arm must not travel more than a total of +/-60º
from neutral position. When the aircraft controls are centered, the arm of the servo should be
perpendicular to the attaching push rod. If this is not the case, we recommend adjusting the
length of the push rod or consider a different mounting point. For maximum efficiency and the
lightest drag on the flight controls, you should choose the smallest servo that provides sufficient
torque to move and hold the flight controls with a minimum of “slippage”. A diagram of servo
torque versus mount position is shown on page 6-9.
CAUTION: The servo arm must not rotate even near to the point called OVER
CENTER, the point at which the primary aircraft control would “lock up”. Over center
happens when the angle between the servo arm and the attached push rod becomes so
great that the control system cannot drive against the servo arm. To protect against this
possibility, a Range of Motion Limiting Bracket is supplied with each Dynon Avionics
servo. These brackets are drilled so that they can be mounted at different angles as
required (18° intervals). The brackets are supplied for the protection of the pilot, and we
recommend that the Range of Motion Limiting Bracket be installed to ensure that an
OVER CENTER condition cannot occur.
Once a suitable mounting point for each servo has been determined, the next step is to fabricate a
mount for the servo to attach to the aircraft. Generally this will be a bracket made of sheet metal
or corner stock. Dynon recommends using 6061 T6 aluminum with a minimum thickness of