Diamond DA20-C1 - Flight Controls - Elevator Trim; General; Description

Page 1
Rev 16
27-31-00
Flight Controls
DA20-C1 AMM
DA201-C1
30 Oct 09
FLIGHT CONTROLS - ELEVATOR TRIM
1. General
The DA20-C1 aircraft has an elevator with an electrically-operated trim system. This lets you trim the
aircraft for different center of gravity positions. A switch on the center console controls the elevator trim.
An indicator tells the pilot the trim position. An electric actuator moves a spring system. Alternatively,
aircraft may be fitted with control stick mounted trim switches.
Control stick mounted trim switches are located on top of each control stick, aft of centre. The switches
are positioned so that they can be easily operated by thumb. Forward movement of either switch gives
nose down trimming and aft movement of the switch gives nose up trim. The trim switches control
electrical relays that supply electrical power to the electric pitch trim motor. If the switches are operated
in opposing directions at the same time the trim motor will not operate. Operation of the trim switches in
the same direction and at the same time will cause the trim motor to operate in that direction.
2. Description
Figure 1 shows the elevator trim control system. The trim control system has the following parts:
- A 3-position rocker-switch is located in the center console or the switches are located on each
of the control sticks depending on aircraft configuration. The switch (s) is spring-loaded to the
middle (off) position
- A trim indicator located on the instrument panel. The indicator has a vertical row of light-
emitting diodes
- A spring-mount assembly which attaches to the vertical control rod for the elevator. The
spring-mount assembly has 2 springs. The vertical control rod goes through the bore of the
springs. The top of the top spring (and the bottom of the bottom spring) have mounts. Roll pins
attach the mounts to the vertical control rod. A spacer bush between the springs has a groove
for the fork assembly on the trim actuator.
- An electrical trim actuator. Two brackets attach the trim actuator to the aft face of the spar in
the vertical stabilizer. A snubber attaches to the output rod of the trim actuator. A fork
assembly on the snubber engages with the spring-mount on the vertical control rod for the
elevator.
The trim system used on the DA20-C1 aircraft is not adjustable.